sugar candy experiment

Get Your ALL ACCESS Shop Pass here →

Sugar Crystal Experiment

This is an absolutely sweet science experiment! Grow sugar crystals and make homemade rock candy with this simple chemistry experiment. We can show you how to set up a science fair project to go along with it! Growing sugar crystals is a fun and easy science experiment for kids. .

Incredible Edible Science

Who doesn’t love science you can eat ? Grow sugar crystals for tasty chemistry , and the kids will have a blast learning all about crystals!

Crystal science has fascinated humans for thousands of years. Many of our precious gemstones are formations of crystal. Check out other crystal science projects like our salt crystals and borax crystals. You can also make edible rock candy geodes .

This sugar crystal experiment uses the same saturation principles and makes a saturated solution to form the crystals. Growing crystals is fun for kids and teaches them about solutions, molecular bonds, patterns, and energy. All from two ingredients: sugar and water!

Oh, and of course, you can incorporate it into a geology lesson , too!

💡 You can eat these crystals when you are done growing them, making it even more fun!

How to Grow Sugar Crystals

Why do we call chemistry experiments like this kitchen science ? It is because all the needed supplies come straight out of the kitchen. Easy!

Note: You will need to set aside 8+ days to complete this sugar crystal experiment.

• 1 cup water
• 4 cups sugar
• Edible glitter
• Food coloring

Also check out more fun ideas for mason jar science! Once you set up your sugar crystal experiment, try a few more quick science in a jar ideas!

HOW TO MAKE SUGAR CRYSTALS

STEP 1. The day before starting your sugar crystal experiment, cut a piece of string a little longer than your jars. Tie one end of the string to a straw. Tie a knot in the other end.

Get the strings wet and coat them in sugar. Let them dry overnight.

STEP 2.   Add four cups of sugar and one cup of water to a saucepan the following day and heat until boiling. Heating the water to dissolve the sugar is the key to making your supersaturated solution.

Create the sugar solution: Heat water in a saucepan until it just begins to boil. Remove the saucepan from the heat. Add granulated sugar to the hot water, stirring continuously, until no more sugar dissolves. Keep adding sugar and stirring until you see some sugar settling at the bottom of the saucepan without dissolving further. This indicates that you have a saturated solution.

STEP 3. Pour your sugar mixture into the jars. Add edible food coloring to each jar and add some edible glitter.

STEP 4. Lower the string into the jar and place the jars in a safe place. Leave the sugar crystals to form for at least a week.

SUGAR CRYSTALS: DAY 8

Once the sugar crystals are as big as you want them, remove them from the sugar solution. Lay them on a paper towel or plate and let them dry for several hours.

Inspect the sugar crystals with a magnifying glass or microscope when they are dry . How are the crystals similar? How are they different? What can you see in the microscope or with a magnifying glass that you can’t see with your eyes?

Fabulous, edible science is at your fingertips when you explore science in the kitchen with your kids!

FREE Geology Activities Guide

Just because it’s food or candy doesn’t mean you can’t apply the scientific method .

Sugar Crystal Science Fair Projects

Science projects are an excellent way for older kids to show what they know about science. They can also be used in various environments, including classrooms, homeschooling, clubs, and groups.

💡 Kids can take everything they have learned about using the scientific method , stating a hypothesis, creating variables , and analyzing and presenting data.

Want to turn this sugar crystals experiment into a cool sugar crystallization science project? Check out these helpful resources below. Take a look at the science fair project outline below to get started.

• Science Project Tips From A Teacher
• Science Fair Board Ideas
• Easy Science Fair Projects

Sample Science Procedure to Grow Sugar Crystals:

• Begin the project by explaining what crystals are and the process of crystallization. Take a look at different examples of sugar crystals to learn more.
• Formulate a hypothesis. For example, “I predict that crystals will grow faster/bigger in a solution with more sugar.”
• Prepare the different containers for growing crystals according to the steps above.
• Encourage kids to set up multiple containers with different variables to test.
• a. Vary the sugar concentration in the solution (e.g., 1 cup sugar:1 cup water, 1 cup sugar:1/2 cup water, etc.).
• b. Compare different types of sugar (granulated sugar, powdered sugar, brown sugar).
• c. Test the effect of temperature by placing one container in the fridge and another in a warm place. d. Investigate the impact of time by checking the crystals’ growth at regular intervals (e.g., every day for a week).
• Have the kids observe the containers regularly and record them in a notebook. They should note changes in crystal size, shape, and formation patterns. Use our free science fair pack to help!
• Help the kids analyze their results and draw conclusions based on their observations.
• Discuss whether their hypotheses were supported and if they noticed any unexpected findings.
• Prepare a display board for the science fair, showcasing the experiment’s steps, observations, and results.

This project provides an excellent opportunity for kids to learn about the scientific method, observation, and the fascinating world of crystal formation while enjoying some sweet treats!

More Fun Edible Experiments

See if you can turn one of these science experiments into a science fair project!

• Strawberry DNA Extraction (not edible, but a great project)
• Make Edible Geodes
• Fizzing Lemonade
• Maple Syrup Snow Candy
• Homemade Butter
• Ice Cream In A Bag

Printable Science Projects For Kids

If you’re looking to grab all of our printable science projects in one convenient place plus exclusive worksheets and bonuses like a STEAM Project pack, our Science Project Pack is what you need! Over 300+ Pages!

• 90+ classic science activities  with journal pages, supply lists, set up and process, and science information.  NEW! Activity-specific observation pages!
• Best science practices posters  and our original science method process folders for extra alternatives!
• Be a Collector activities pack  introduces kids to the world of making collections through the eyes of a scientist. What will they collect first?
• Know the Words Science vocabulary pack  includes flashcards, crosswords, and word searches that illuminate keywords in the experiments!
• My science journal writing prompts  explore what it means to be a scientist!!
• Bonus STEAM Project Pack:  Art meets science with doable projects!
• Bonus Quick Grab Packs for Biology, Earth Science, Chemistry, and Physics

• Pingback: 30 Incredible Chemistry Experiments - 123 Homeschool 4 Me
• Pingback: How to Make Rock Candy | CandyWarehouse Blog
• Pingback: Thanksgiving Lesson Plans for a Kid Friendly STEMs-Giving! | Little Bins for Little Hands

I am a librian and I just wanted to say that I love your website!! We have been doing take-home kits instead of in person youth programming due to COVID, and your STEM projects with explanations of the science are a real life-saver!

Love it! So happy to hear that we’ve been of help to you in these difficult times!

Comments are closed.

Subscribe to receive a free 5-Day STEM Challenge Guide

~ projects to try now ~.

• Skip to primary navigation
• Skip to main content
• Skip to primary sidebar
• Skip to footer

We are not Martha

• Where I've Been

Apr 19, 2021 · Modified: Jul 16, 2021 by Sues · This post may contain affiliate links, uses cookies, and generates income via ads · View privacy policy + disclosure statement linked in footer · 93 Comments

How to Make Rock Candy

Homemade rock candy is easy to make! It simply requires a little bit of patience and a whole lot of sugar. Whether you're making the sweet treat to enjoy for dessert or as a science experiment to do with your kids, you'll be amazed at how fun DIY rock candy is.

This post was first published in August 2011, but has been updated with much improved instructions and new photos in 2021.

So, you want to make your own rock candy? Yay! I first wrote this tutorial back in 2011 when I decided I wanted to make rock candy as table decor for my wedding.

Well, let's just say once I attempted actually making rock candy I realized that was not going to happen for several reasons:

• Rock candy requires A LOT of sugar to make. If I wanted 200 sticks of rock candy, it would take about 200 cups of sugar (that's if I re-used each sugar solution one time).
• Rock candy requires time and patience to make. In the quantities I wanted, I should have started making my rock candy at least a year in advance and would have been working on it nearly every day during that time.
• I'd have to live with mason jars of rock candy growing all over my (at the time) tiny apartment.

Needless to say, I did not make rock candy for my wedding.

But 10 years later, I've decided to update this post because my initial rock candy instructions were not that great- I shared my experience with you, but my results weren't ideal.

I've recently started making rock candy again and now have a process down that should work for everyone!

I've also included lots of FAQs that I've received over the years, along with some tips and tricks to make DIY rock candy making easier for you.

What is Rock Candy?

Rock candy is sometimes called "sugar candy" and for good reason! It's actually made completely of large sugar crystals. It often comes in pretty colors and is sold in all kinds of candy stores.

If you've ever made simple syrup before, making rock candy is similar... Except you'll oversaturate the syrup solution (AKA add too much sugar to it) and then let it cool and rest so sugar crystals can form.

Because the solution is supersaturated, that means it can't possibly absorb the sugar at the cooler temperature. Therefore, as the solution cools, it becomes unstable and all the sugar can't stay in the liquid, so it attaches itself to the skewer.

Why Should I Make My Own?

Of course you can easily purchase rock candy in a store or online, but making your own is fun. Whether you want to enjoy it yourself or give it out as gifts, it's easy to do. But if you need it in bulk for wedding decor, you'll want to plan VERY well in advance!

Another reason to make your own rock candy is because it's a great science experiment. You and your kids can learn all about the process of crystallization and different saturations of solutions.

Also, rock candy makes for super fun cocktails (you can also make fun mocktails for your kids)!

In conjunction with making rock candy, you may also want to try making other candies, like homemade fudge and gummy candy. Here's a great guide to sugar chemistry .

How Long Does it Take to Make?

The solution for rock candy is really easy to make and doesn't take long at all. BUT once you make the solution, you need to let it sit for 6-7 days so the crystals can form.

So, yes you need some patience. But it's also fun because you can check on your jars every day to see how your crystals are growing!

Equipment Needed

You may already have everything you need to make your own rock candy as it only requires a couple simple ingredients and a few household items. Here's what you need:

• Granulated Sugar (for 5 sticks of candy, you'll need 10 cups)
• Food coloring (if you want to add color to your candy)
• Mason jars or other receptacles to hold sugar solution. I recommend a standard 16 oz. mason jar .
• Skewers or sticks to make rock candy on. I use a simple wooden kabob skewer . But you can actually buy rock candy sticks to use for a more professional look.
• Clothespins or chip clips to balance stick on jar (you can't let the stick touch the bottom of the jar).

This "recipe" will make 5 sticks of rock candy. Since the candy will all grow in separate jars, you can make a variety of colors with this one recipe. I like to keep at least one jar clear as it's the easiest to be able to monitor growth!

To start, you need to coat your skewers or sticks in granulated sugar. The purpose of this is to "seed" the rock candy and give the crystals something to adhere to as they start to grow.

I trim my skewers a bit before using them since they're pretty long and have a pointy sharp end.

Submerge the skewers in water, coat them in sugar, and then set out to dry.

I like to do this a day ahead of time, but as long as you let them dry for an hour, they should be fine.

The next step is to prep your jars so that the process is easy once you make your sugar solution.

Make sure your jars are clean and not cold (I recommend running hot water through them before using). Attach a clothespin or chip clip to each skewer and then balance over the top of jars.

Be sure your skewer is hanging about an inch from the bottom of the jar as the rock candy crystals will stick to the bottom of the jar and will make it tough to remove skewers.

Set it all up, but then take the skewer out of the jar- you'll add it back in once your sugar solution is in.

Now it's time to make the sugar solution. Add 4 cups of water to a large saucepan. Bring to a boil and then start adding sugar in one cup at a time, stirring with a wooden spoon and letting each cup fully dissolve before adding the next.

You'll notice it becomes harder and harder for the sugar to dissolve as you add more in and the sugar will start to clump before dissolving, like this:

That means your solution is supersaturated and you should have no problem growing crystals. Woo hoo!

Once your final cup of sugar has been dissolved, let mixture simmer for about 5 minutes before removing from heat.

Remove the saucepan from the heat and let the mixture rest for about 15 minutes.

Now, divide the mixture between your 5 prepared jars. And stir in your food coloring at this time.

I highly recommend bringing your jars to where they'll be resting for the next 6-7 days before you place the skewer in the jar. Be sure to use caution when moving the jars as they will be very, very hot.

Once the jars are in their resting spots, place prepared skewers into solution. You'll want to try your best not to move jars around much once skewers are in place.

Now comes the tough part... Waiting for your rock candy to grow!

Luckily, things will start happening fairly quickly and you should see crystals starting to grow on your sticks within a day. Here's how mine looked after 24 hours:

Here they are after 48 hours:

And here they are after 72 hours:

You can remove the skewers from the jars whenever you want, but I recommend giving them at least 6 days to fully form.

When you're ready to remove rock candy sticks from jars, use your finger to gently crack the hardened sugar on top of the jar and gently wiggle the stick to release. Like this:

Let the syrup drizzle from stick. I recommend setting the candy over an empty jar or bowl to let it drip or placing it on a paper towel.

Then you're ready to enjoy your incredible homemade rock candy!

How cool is that??

Can I Re-Use Sugar Solution?

I got a lot of questions about this on my previous post, so I decided to do a little experimenting this time around.

Once you take the sticks out of your jars, you'll likely feel wasteful pouring the rest of the sugar solution in the trash. So, can you re-use it? The short answer is yes!

But before you just plop another sugar-coated stick in the solution, I recommend that you pour it back into a saucepan and bring it back to a boil. Add another ¼ cup sugar in it and let it simmer for a few minutes. Then pour it back in the jar.

I re-used a couple of my solutions without re-heating and adding more sugar to the solution and here's how they came out after a week:

Here's what happened when I did re-heat and add an additional ¼ cup sugar:

That's some definite proof that you'll want to re-boil the solution and add more sugar!

Why Isn't My Rock Candy Growing?

Great question! Making rock candy can be a bit finicky and there are lots of reasons it may not work on your first try. However, if you follow these instructions closely and use the full 10 cups of sugar in 4 cups of water, you should have a supersaturated solution and your chances of it working are high.

If your sticks don't seem to have crystals growing at all after a few days, it may because your sugar solution wasn't oversaturated for whatever reason. In that case, you can put the mixture back into the saucepan, bring it to a boil and add in another cup of sugar. Stir to dissolve. Add more sugar in if the first cup dissolved easily.

You'll want to use new sugar-coated skewers, too.

I went through this process the first time I made rock candy and had a fail and it definitely seemed to help as crystals started growing after I did it.

Also be sure to double-check that your jars are clean and not cold and that you didn't move your jars around once you added the stick in.

How Can I Make Rock Candy Fast?

Unfortunately, there isn't really a way to make rock candy grow quickly. I have heard that putting the jars in the fridge will speed up the process a bit, but I haven't tried this myself.

You can take your rock candy out of the jar after just a couple days, but your sticks will probably be a bit sparse.

How to Store Candy

Store your rock candy in a cool dry place. If you're planning on keeping it for a while or giving it as gifts, I recommend wrapping them in cellophane wrappers, like these .

When stored properly, your rock candy should stay good for a year.

Helpful Tip & Tricks

Once you have the process down and understand the science behind it, making your own rock candy is super simple! But I do have some tips and tricks that should help you troubleshoot if you're having problems:

• Make sure your mason jars are completely clean and not cold. I store a lot of my mason jars in my basement (which is chilly), so I always clean them out with hot water before using them.
• Do not skip the step of coating your sticks in sugar. It's very important that the crystals have something to adhere to as they grow (otherwise they'll likely just grow to the bottom of the jar).
• I recommend using a concentrated food coloring or gel to ensure that you can add enough color without adding too much liquid to the solution. These are my favorite colors (they're not gel, but are very saturated).
• I recommend making the color a bit darker than you think you should as it will look lighter once the crystals form.
• You can add flavoring to the rock candy if you want, but similarly to using food coloring, try to use a concentrated flavoring so you don't have to add too much liquid to get the flavor level you want.
• Once you've poured your sugar mixture and placed your sticks in the jars, take care not to move them or jostle the sticks.

As you can see, DIY rock candy is pretty easy to make as long as long as you understand the process. It mostly just requires patience... And a whole lot of sugar!

After making rock candy at home, I have a whole new appreciation for the candy and can certainly understand why a company may charge top dollar for it (though I'm sure the use of machinery makes it much easier!).

Don't forget to check out my recipe for rock candy cocktails if you're looking for a fun way to utilize your candy!

Have you ever made your own rock candy at home?

DIY Rock Candy

Ingredients.

• 5 wooden skewers
• 5 mason jars (I recommend 16 oz)
• 5 clothespins or chip clips
• 4 cups water
• 10 cups granulated sugar, plus more for coating skewers
• Food coloring

Instructions

• Submerge skewers in water, coat them in sugar, and then set out to dry. I like to do this a day ahead of time, but as long as you let them dry for an hour, they should be fine.
• Make sure your jars are clean and not cold (run hot water through them if necessary). Attach a clothespin or chip clip to the top of each skewer and then balance over the top of jars. Be sure your skewer is hanging about an inch from the bottom of the jar as the rock candy crystals will stick to the bottom of the jar and will make it tough to remove skewers.
• In a large saucepan, bring water to a boil. Add sugar in one cup at a time, stirring with a wooden spoon and letting each cup fully dissolve before adding the next. You'll notice it becomes harder and harder for the sugar to dissolve as you add more in.
• Once your final cup of sugar has been dissolved, let mixture simmer for about 5 minutes before removing from heat. Let mixture rest off the heat for about 15 minutes.
• Divide sugar solution amongst the 5 prepared jars. Stir in food coloring at this time. I recommend bringing your jars to where they'll be resting for the next 6-7 days at this time. Be sure to use caution as the jars will be very hot. Once they're in their resting spots, place prepared skewers into solution. You'll want to try your best not to move jars around much once skewers are in place.
• You'll likely see little crystals forming within hours, but you'll want to let the jars rest for 6-7 days to let sugar crystals fully form.
• When ready to remove rock candy sticks from jars, use your finger or a fork to gently crack the hardened sugar on top of the jar and gently wiggle the stick to release. Let solution drizzle from stick (I recommend setting the candy over an empty jar or bowl to let it drip) before enjoying the candy.
• If you want to re-use the sugar solution to make more rock candy, pour solution into saucepan and bring to a boil (you can add any sugar crystals that have already formed, but if you can't get them all, simply clean them out of the jar before re-using). Add in an additional ¼ cup of sugar and let simmer for a couple minutes. Remove from heat and let cool for 10 minutes before pouring into a clean jar.

Useful Products

More Dessert Recipes

Reader Interactions

Kate Deeks says

August 17, 2011 at 7:50 pm

Ha! I loved the rock-candy camera setting. Would love to make crystals, but not so interested in the candy eating. Sounds like a fun experiment.

vanillasugarblog says

August 17, 2011 at 7:53 pm

remember as a kid how much we loved having these? i was horrid at making caramel until I finally got a good thermo and MADE myself set up camp at the stove to babysit the caramel.

lynn @ the actor's diet says

August 17, 2011 at 7:55 pm

i remember them making this (and peanut brittle) in science class. i was so jealous of those kids!

August 17, 2011 at 8:41 pm

Rock candy is so pretty! I made it once when I was a kid and a trail of ants found their way to it from under my back door.

August 17, 2011 at 8:43 pm

sue, this is very pretty, it's a piece of art. just like clusters of crystals !! It's amazing to know just by boiling sugar syrup can form into these. oh, just voted for your site. Have a happy day!

August 17, 2011 at 9:25 pm

wedding rock candy...what a cute idea! you could have jars of rock candy forming all over your house haha 🙂

August 17, 2011 at 9:26 pm

I only have about 65 peeps coming to my wedding. I might be able to make this happen! Thanks for the inspiration!!!

August 17, 2011 at 9:34 pm

Congrats! I will go vote now! I had no idea making rock candy was such a process! The results are so pretty! I def do not have the patience

August 17, 2011 at 10:56 pm

Hi Susie! You and Chris looked like you at least enjoyed making these! And they are so pretty. I just voted for your website, and will return tomorrow to do it again!!

Lauren at Keep It Sweet says

August 18, 2011 at 7:10 am

OMG, so much fun! This would completely make me feel like a kid:-)

Joanne says

August 18, 2011 at 7:26 am

Wow who knew that making rock candy was such an ordeal! But totally worth it for a once-in-a-lifetime experience.

Jenn's Food Journey says

August 18, 2011 at 8:45 am

I made rock candy once when I was about 12!! lol Your post brings back great memories of that!! And they look beautiful 🙂 Congrats on being nominated.. I'm going to vote for your ladies right now!

newlywed says

August 18, 2011 at 10:01 am

Well, it sure looks great! I had DIY-fever for my wedding too. Then I woke up one day and remembered how much I hate crafts. And bought everything. Except for the favors, which I cooked with my mom...because at least I like cooking!

Emily @ A Cambridge Story says

August 18, 2011 at 10:07 am

You definitely make this look easy - who knew that rock candy had to "grow". It probably is a little untenable for homemade wedding favors but I'm really impressed that you did this!

Erica @ In and Around Town says

August 18, 2011 at 10:46 am

Totally did this in 3rd grade science, but think I need to do this again! So much fun 🙂 Congrats on the nomination!

August 18, 2011 at 11:03 am

I think your photos look great! Also, it was interesting to read about your experience making rock candy, I didn't realize it was such a simple process, but with such varied results! Very cool.

August 18, 2011 at 11:08 am

I just bought Sugarbaby and have been planning to try the rock candy recipe just for fun. There's a suggestion in there to use toothpicks and make mini rock candy... which could speed things up if you haven't completely given up on making your own for your wedding.

August 18, 2011 at 12:31 pm

Yumm! I never successfully made rock candy as a child, not convinced I'd be too good at it as an adult either though... haha

Michelle Collins says

August 18, 2011 at 1:30 pm

Congrats on the nomination!

CookiePie says

August 18, 2011 at 1:55 pm

WOW - homemade rock candy - that is amazing! For your wedding, you can show everyone the pictures of your beautiful rock candy 🙂

5 Star Foodie says

August 18, 2011 at 8:34 pm

How fun to make this at home, very neat!

Shannon says

August 19, 2011 at 12:12 pm

how fun!! that is awesome 🙂

Andrea Kazilionis says

August 19, 2011 at 8:26 pm

So excited about this post! I can't wait to try this kitchen science project and enjoy the delicious outcome...!

Kerstin says

August 21, 2011 at 11:34 pm

What a fun post - I had no idea how to make rock candy! Great wedding favor idea too 🙂

August 22, 2011 at 3:49 pm

Looks great! Can't imagine making 200 of those! Man, that is a lot of sugar for so few sticks!!

Elina (Healthy and Sane) says

August 25, 2011 at 5:36 pm

Obviously you're not going to make these for the wedding but at least you now know how to make them (I love discovering such things). Awesome little project! 🙂

Rozzie says

August 31, 2011 at 4:06 pm

Wonderful post! Great to see the photos in progress and your commentary was awesome. Thanks for sharing.

Dorcas says

September 24, 2011 at 3:04 pm

Ironically I had actually planned on trying this tomorrow. Last night I was looking something else up in my Joy of Cooking and thought it'd be really cool to try. I'm so glad I saw your blog because I'm going to do more investigating before I begin. My book says to take a disposable square 8" aluminum pan, punch 7-8 holes 1/2" up on two opposite sides. Then lace string back and forth. Then you pour sugar mixture (boiled to 250- hard ball stage) over string. String will be immersed. Then cover pan & leave undisturbed 36-48 hours at least. Then wait some more until it's all crystalized. Cut strings and lift it out of pan. (I guess it's solid now - idk) put on baking sheet in 200 degree oven to dry. Says to use strings as decoration or knock crystals off. Store in air tight container at room temp. Usage idea- pile crystals high in bowl at party for fancy sugar for coffee. I didn't copy recipe here. Just gave you the highlights. As you can imagine I now have a headache. Lol. You used 3.5 cups of sugar. Mine is 2.5 cups sugar, 1cup water and a pinch of Cream of Tartar.

simone says

October 28, 2011 at 9:58 am

Featured you in our Food Trends article this week! Looks delicious and gorgeous.

November 13, 2011 at 8:21 pm

I have had varied luck over the last few years, making rock candy. Like yours, some stuck to the stick, some turned to a huge blob in the bottom of the jar. Luckily for me, I was making them to tie onto Christmas packages, and not for a wedding, or the pressure would have gotten to me! I ordered candy flavorings, and added it to my sugar solutions. Then co-ordinated it with the color-mint or irish cream went with green, for example. These were made to use for stirring coffee, sweetening it, and giving it some specialty flavors! A great gift in itself. If you have serious coffee drinkers on your list!

Charles says

November 19, 2011 at 12:47 pm

my took 4 months...for one crystal to grow on it (:

Charlie says

December 04, 2011 at 9:52 pm

This would be a great Girl Scout troop project!

MYT CR8TiV says

March 06, 2012 at 10:22 pm

I made these in Science class when I was a kid. We used Hard Candy Flavoring drops to enhance the taste. You could use those so it doesn't just taste like bland crystallized sugar.

May 02, 2012 at 11:11 pm

I just had to do a chemistry experiment dealing with recrystalization. We did the same process of boiling the water and sugar to supersaturate it, after it was completely mixed we placed the beaker in an ice bath and the crystals automatically formed. I wonder if that process would work to speed up the rock candy process.

Dakota says

June 25, 2012 at 6:25 pm

Thanks, this'll be great to try! I heard that you can flavor them with flavoring oil/extract, im not sure if I could stand pure sugar on a stick. 🙂

August 09, 2012 at 1:15 pm

I loveee this site! I'm using rock candy in my wedding too, Purple and White Rock Candy in a vase to make a "bouquet". I've searched online for some to buy, but it is kind of expenses so I thought I would try to make my own. Sounds easy, right? HA! 🙂

Jacob Crim says

October 19, 2012 at 10:34 am

Could I pour the liquid into a baking sheet then break it up once its dried? I am trying to make "blue meth" like in Breaking Bad for my Halloween costume.

October 20, 2012 at 10:40 am

@Jacob- You could try! As you saw, making this wasn't exactly easy for me... So I'd try a few batches now and hopefully one will be ready in time 🙂

A.L. Designs Jewelry says

December 12, 2012 at 8:54 am

Look so fun and yummy 🙂

January 19, 2013 at 3:25 pm

Just a thought in candy making. I was always told to making candy on sunny days. Candy wont set up if not. I know this is true for fudge, and would make sense for this as well.

VinPro elegance says

May 09, 2013 at 9:28 pm

Thanks!!Thanks, great to try!

Fattaneh says

September 26, 2013 at 12:31 am

Thanks for sharing your experience! I'm gonna try it and I hope the result is good.

November 19, 2014 at 9:51 pm

These are awesome. I think imperfection looks more beautiful. Cant wait to do this with my daughter.

Gourmet Candy says

December 29, 2014 at 1:34 pm

I really liked the rock candy and you should also go to this site they got some pretty good candy here too http://www.myidolpops.com/

Heather says

October 24, 2015 at 8:02 pm

Well I am really glad I read this. I have been attempting to make rock candy for a baby shower. I have watched countless videos. Everyone makes it look so easy. For some reason the sugar I bought never seems to get clear. I stir and stir and stir. By the time it comes to a boil and I pour it into the jars within an hour its like a solid hard clump. I have three weeks to complete this task lol. I will not give up 😉

November 28, 2015 at 1:17 pm

I heard to dip skewers in the liquid solution and roll them in sugar before putting them in the jar. The sugar will crystallize on the other crystals.

Erica Watson says

January 12, 2016 at 12:39 am

I was wondering how did you make rock candy .now I know how to make it me and my grandkids can make that on family night

July 02, 2016 at 9:03 am

This is truly amazing!!!!!! The only thing I don't like is that it won't let me see the ingredients

July 02, 2016 at 9:04 am

This is truly amazing!!!!

kaidadraco says

February 14, 2017 at 2:05 pm

best thing ever! XD

Zareena says

April 09, 2017 at 10:27 pm

Hmm...i wonder if the sugar will stick on a heart shaped-wire? We can make a heart rock candy for Valentine's day! ??

April 19, 2017 at 2:55 pm

@Zareena Definitely worth a try! It wasn't the easiest to make, but maybe I'll try again soon since it's been many years since my first attempt 🙂

Shannon B says

July 02, 2021 at 11:02 am

Olivia Michaels says

August 29, 2021 at 11:44 am

Britney D McClenney says

November 27, 2021 at 1:39 pm

I was wondering if we could use Kool aid packets as the flavor and color for the rock candy?

November 27, 2021 at 5:12 pm

Hi Britney! I haven't tried this, but I do think it will work. The added sugar from Kool Aid should be fine and the color and flavor would work well!

Dorcas Berthold says

December 05, 2021 at 5:12 am

December 08, 2021 at 7:57 am

someone says

February 08, 2022 at 3:37 pm

Katrina says

February 11, 2022 at 10:46 pm

Karley says

March 20, 2022 at 5:28 pm

To redo it, it is per jar? Like do 1 jar at a time or do you add them all back in and then put the 1/4 cup of sugar?

March 24, 2022 at 10:16 pm

@Karley- It's per jar. If they're all the same color and flavor, you could do them all together, but still add 1/4 cup per jar. It seems like a lot, but the crystals need a lot to grow!

Allison says

May 26, 2022 at 1:41 pm

I tried this but the whole jar turned into wet but fairly solid granular sugar the first day - did I add too much sugar?! I was halving the recipe so maybe I messed up…

May 26, 2022 at 2:38 pm

Hi Allison! I haven't heard of this happening, but it could be that you used too much sugar and/or you didn't boil it long enough. Generally, if you "oversaturate" the solution with too much sugar, the extra sugar will just chill at the bottom of the jar as it cools, but if there was a lot of it, I could see how it could start hardening in the bottom of the jar and on the sides fairly quickly. Let me know if you try again!

May 31, 2022 at 7:31 pm

I did it exactly like the recipe said and I'm 4 days in and not one Crystal it hasn't done anything

June 02, 2022 at 11:38 am

Hi Erica! Unfortunately, rock candy can be VERY finicky and though I've made rock candy tons of times, I've even had issues with it before. There are SO many factors that can effect growth. It IS odd you didn't have any crystal growth at all, so I wonder if enough sugar was added and if it was dissolved into the water all the way. Sometimes rock candy doesn't grow perfectly on the stick or string, but with enough sugar properly dissolved, there should at least be SOME crystal growth in the jar. Let me know if it progressed at all or if you need any further help trouble shooting!

June 07, 2022 at 9:37 pm

August 20, 2022 at 2:43 pm

Hello! Science teacher here. Was planning to try this with my chemistry class but our classes are only 50 minutes long. Can I make the sugar solution early, like at home before school and bring it in and it still work? They are my 4th period class. Can I make at home then microwave to liven up the sugar before class?? Thanks for your help!

August 20, 2022 at 3:07 pm

Hi Cindy! With 50 minutes, I think you should have enough time to do the project in class... It may take 30-40 minutes to dissolve all the sugar into the water (but can be faster if you can get the water boiling before class starts!). Then it can just be poured into the prepared jars... it will take close to a week for rock candy to fully form, but will be fun to check in on every day to see the crystals forming! However, if you want to do it ahead of time, I think you could prepare the sugar saturated solution and then re-heat in class, but you may need to add a little more sugar when re-heating as sugar crystals may already be starting to form as it's cooled. But this should definitely work as I've re-used the solution leftover in jars to make more rock candy with no problem. Let me know how it goes!

December 22, 2022 at 11:31 am

Hi Sue, I use to work in a coffee shop and we kept flavored sugars. A vanilla bean in the sugar for vanilla, etc. I wonder if you couldn't flavor the sugar before hand instead of adding a concentrate to it. Norma

December 22, 2022 at 2:35 pm

Hi Norma- I think that's a great idea!

March 28, 2023 at 11:15 am

Loved the directions with pictures! Just wondering, if you could put two sticks in at once, on opposite sides of the jar?

March 28, 2023 at 12:09 pm

Hi KC! I haven't tried using 2 sticks at once, but as long as your jars are wide mouth jars, you should be able to do this!

Marlene Pollitt says

May 10, 2023 at 10:53 pm

Melissa E says

June 07, 2023 at 5:39 pm

June 09, 2023 at 12:39 pm

Hi Melissa! Yes, I use pint jars for my rock candy. How much extract you use will depend on how strong you like the flavor, but I'd say a teaspoon should work. You shouldn't need to ad more sugar for that small amount of extract. If you ad the extract in while the mixture is still boiling, it will burn the alcohol off. And how much food coloring really depends on the type you're using- I recommend using a concentrated food coloring and you'll only need a few drops. I hope that's helpful!!

Brenda says

June 09, 2023 at 6:27 pm

Hello, I made my first batch and they turned out wonderful. Second batch, not so much. Third batch, well, what I got was sugar slushies and big clumps of sugar stuck to the bottom of the jars. Obviously I’m an idiot. What can I do to save my starter if I can save it? I need help. That’s a lot of sugar to just discard.

June 11, 2023 at 4:28 pm

Hi Brenda- Yes, I have some advice on this in my post! You can even re-use the solution if your rock candy grows. Just pour it back into a saucepan and bring to a boil- you will want to add some more sugar. Let me know how it goes!

November 17, 2023 at 10:24 pm

Would it be ok to cover the jar with aluminum foil, to keep dust from getting inside? Or do they need to be left open so water can evaporate? I wouldn't be pressing the foil around the sides tightly, just kinda loosely covering it. Our house became super dusty all of a sudden after my brother moved in & nothing seems to help keep it at bay🤢 I like the idea of reusing the left over solution after the first sticks are finished, but without covering the jars I'd feel too disgusted to do so.

BTW, here's a tip to get bigger crystals... Supposedly the slower the solution cools, the bigger the crystals will turn out... So maybe it'd be helpful to wrap the jars in foil or use a thermos type container to make the candies in? Only prob with the thermos-you couldn't see the progress until you removed the stick. I'm sure you guys can come up with plenty of ways to try and slow down the cooling process. It actually makes sense that the quicker the solution cools the smaller the crystals would be, since "heat" is just a term for how fast particles are moving.

November 18, 2023 at 12:05 am

Hi Heather- Yes! As long as you're not totally sealing the foil around the jars, I think it would be perfectly fine to loosely cover them. Just make sure some air can still circulate.

And yes, I bet wrapping the jars in foil or towels could help slow the cooling down a bit- great idea!!

Kendyl says

January 12, 2024 at 3:49 pm

January 20, 2024 at 6:41 pm

January 21, 2024 at 9:20 pm

Hi Kat- I'm really sorry to hear that! Like I mention, making rock candy is an extremely finicky process and many factors can determine the outcome. Generally if your whole jar crystalizes, this is due to the jar being moved or disturbed too much or from temperature fluctuations after your solution is in the jar (like if the room is warm during the day and then the temperature drops at night). It can also happen if some sort of debris getting into the jar. All of the same factors can create "cotton candy" or "fluffy" looking candy, so I am thinking one of those things may have created the issues. I hope that's helpful! I know it's frustrating when experiments don't work after spending so much time on them (and rock candy takes SO much time), but I hope you'll try again at some point because lots of people have had success with this "recipe!"

February 25, 2024 at 5:38 pm

April 09, 2024 at 4:39 pm

April 10, 2024 at 10:07 pm

Hi Tes! I haven't tried doing more than 1 in a jar, but I think as long as your jars are large enough (I recommend wide mouth jars), you should be able to do this. Just make sure there is enough space in between the sticks for rock candy to grow. Let me know how it goes!

April 11, 2024 at 7:17 pm

April 17, 2024 at 9:38 am

Hi Heather- Yes, you should be able to do this with fewer jars/sticks!

May 20, 2024 at 5:22 pm

If i were to take a rock candy out and put it into a different dye solution would it continue to grow fine so that i get a multi colored rock candy?

May 23, 2024 at 11:51 am

Hi Luke- I haven't tried this, but I do think it should work!

July 29, 2024 at 10:26 pm

I remember trying to make rock candy as a kid. All I remember is it didn't turn out well. lol I tried making this around a yr ago and was so excited that my turned out looking exactly like the ones you buy at the store😃 It took quite a bit longer than a week for enough crystals to form to get to that point tho. I was planning on using the left over syrup to make more, but my idiot brother knocked over the jar, spilling it everywhere! You def don't want that to happen! obv it was an awful sticky mess to clean up!

August 24, 2024 at 3:31 pm

Any tips on storing the crystals? I’m actually wanting to make the crystals for a geode cake and wasn’t sure if these would stick together in a bowl. Thanks

August 27, 2024 at 12:12 pm

Hi Tina! I recommend storing the crystals in an airtight container in a cool, dry spot (not in the fridge). Make sure the crystals are dry before storing and you might want to layer waxed paper in between the candy. I hope this helps and that your cake comes out great!!

Leave a Reply

Your email address will not be published. Required fields are marked *

Rate This Recipe

• Science Notes Posts
• Contact Science Notes
• Todd Helmenstine Biography
• Anne Helmenstine Biography
• Free Printable Periodic Tables (PDF and PNG)
• Periodic Table Wallpapers
• Interactive Periodic Table
• Periodic Table Posters
• Science Experiments for Kids
• How to Grow Crystals
• Chemistry Projects
• Fire and Flames Projects
• Holiday Science
• Chemistry Problems With Answers
• Physics Problems
• Unit Conversion Example Problems
• Chemistry Worksheets
• Biology Worksheets
• Periodic Table Worksheets
• Physical Science Worksheets
• Science Lab Worksheets
• My Amazon Books

How to Make Rock Candy or Sugar Crystals

Sugar crystals are called rock candy because these hard crystals are edible. Sugar (sucrose) crystals are one of the few types of crystals you can grow and eat. You can eat the natural clear crystals or you can color and flavor them.

Rock Candy Materials

You only need a few common kitchen materials for this crystal project:

• 3 cups sugar (sucrose)
• 1 cup boiling water
• food coloring (optional)
• flavoring (optional — good choices include cherry, peppermint, and cinnamon)
• clean glass or plastic jar
• wooden skewer or cotton string

You don’t need string or a skewer to grow sugar crystals, but they are good support structures for making rock candy sticks. Crystals also grow on pipe cleaners, but they probably aren’t food-friendly. The crystals also grow on the bottom and sides of their container, forming a confection that is known as Misri in India and Iran.

You can use different kinds of sugar, but avoid powdered sugar because it often contains anti-caking agents. Anti-caking agents don’t dissolve, so the tiny particles attract crystal growth. While this sounds like a good things, it means you’ll get a mass of small crystals rather than large crystals.

Grow Sugar Crystals

The procedure is really easy.

• Dissolve the sugar in the boiling water. Heat the sugar solution on the stove, or in the microwave if you have trouble getting the sugar to dissolve. Once the sugar dissolves, remove it from heat. If you keep heating it, it hardens and burns.
• Add a few drops of food coloring and flavor, if desired.
• Let the solution cool a bit before pouring it into your jar. You don’t want to get burned!
• Pour the sugar solution into a jar. Place a wooden skewer into the jar or else hang a string into the middle of the jar, tied to a pencil or butter knife.
• Place the container somewhere it won’t be disturbed. If you like, cover the jar with a paper towel or coffee filter to allow evaporation while keeping the crystal solution clean.
• It takes a few days to get good crystal growth. If you see crystals forming on the top of the jar, you can remove them and eat them. If you leave them, these crystals will compete with your stick or string for sugar and will reduce the size of your crystals.
• Remove the crystals and enjoy them! If you want to store the crystals before eating them, keep them in an airtight container so humidity in the air won’t make the rock candy sticky.

If you enjoyed growing sugar crystals, how about trying another easy crystal-growing project ?

How Long Does It Take to Grow Sugar Crystals?

Sugar crystals may appear overnight or it may take several days (weeks) for growth. Sugar crystal growth depends on three main factors:

• Solution Concentration : Crystals don’t start growing until you have a saturated solution , where no more sugar dissolves in the water. Whether or not the liquid is saturated depends on the amount of sugar in the water and the temperature. If you aren’t seeing crystal growth, try lowering the temperature. Refrigeration might do the trick!
• Temperature : Temperature determines when crystals start growing and how big they are. Slow cooling resulting in slower growth, but larger crystal formation. Similarly, quick cooling promotes crystal growth, but you get a mass of smaller crystals. Ideally, slowly cool the hot sugar water down to room temperature (or lower). Quick cooling doesn’t yield great results. Putting the liquid in a window causes temperature fluctuations, so crystals dissolve when it’s warm and form when it’s cool. Avoid the window.
• Humidity : Humid air contributes water to the liquid and slows crystal growth. Dry air evaporates water and aids crystal growth. If you aren’t seeing crystals, try improving air circulation or reducing humidity. The easiest solution is turning on a fan.

About Sugar Crystals

The white granular sugar you buy at the store is sucrose (C 12 H 22 O 11 ), which is a disaccharide consisting of glucose and fructose subunits. Raw sugar is usually golden or brown and contains some natural impurities, but still crystallizes. However, while pure sugar crystals are colorless, raw sugar crystals retain their color.

Sucrose contains covalent bonds and crystallizes using these bonds, too. The molecule crystalizes in the monoclinic space group. The resulting crystal is hard, brittle, and rigid. Examples of other crystals that contain covalent bonds are quartz and diamond.

• Beevers, C. A.; McDonald, T. R. R.; Robertson, J. H.; Stern, F. (1952). “The crystal structure of sucrose”. Acta Crystallogr . 5 (5): 689–90. doi: 10.1107/S0365110X52001908
• Hynes, R. C.; Le Page, Y. (1991). “Sucrose, a convenient test crystal for absolute structures”. Journal of Applied Crystallography . 24 (4): 352. doi: 10.1107/S0021889891002492
• Richardson, Tim (2002). Sweets: A History of Candy . Bloomsbury. ISBN 978-1-58234-229-0.

more in 10-12 years

Make your own rock candy, this experiment requires adult help it deals with very hot liquids be smart and be safe – only do this with adult help., you will need.

• A wooden skewer (you can also use a clean wooden chopstick)
• A clothespin
• 1 cup of water
• 2-3 cups of sugar
• A tall narrow glass or jar
• Clip the wooden skewer into the clothespin so that it hangs down inside the glass and is about 1 inch (2.5 cm) from the bottom of the glass. (as shown)
• Remove the skewer and clothespin and put them aside for now.
• Get a helpful adult!
• Pour the water into a pan and bring it to boil.
• Pour about 1/4 cup of sugar into the boiling water, stirring until it dissolves.

• Have your friendly ADULT carefully pour the sugar solution into the jar almost to the top. Then submerge the skewer back into the glass making sure that it is hanging straight down the middle without touching the sides.
• Allow the jar to fully cool and put it someplace where it will not be disturbed.
• Now just wait. The sugar crystals will grow over the next 3-7 days.

Want colored rock candy? Add food coloring to your sugar water and make sure sure that it is pretty dark in color for the best result.

How does it work?

When you mixed the water and sugar you made a SUPER SATURATED SOLUTION. This means that the water could only hold the sugar if both were very hot. As the water cools the sugar “comes out” of the solution back into sugar crystals on your skewer. The skewer (and sometimes the glass itself) act as a “seed” that the sugar crystals start to grow on. With some luck and patience you will have a tasty scientific treat! Enjoy!

More Images & Video

More from my site

ADS (these ads support our free website)

Share this page.

• svg]:fill-accent-900">

Stay-at-home science project: Grow your own rock candy

By Sandra Gutierrez G.

Posted on May 7, 2020 4:00 PM EDT

7 minute read

Welcome to PopSci’s at-home science projects series. On weekdays at noon, we’ll be posting new projects that use ingredients you can buy at the grocery store. Show us how it went by tagging your project on social media using #popsciprojects.

Any chef would agree that cooking is basically applied science and, unless you are an actual scientist working from home, your kitchen is the closest thing you’ve got to a lab. Following a recipe is essentially the same as running an experiment, and the best part is that you get to eat the delicious result. This project is no exception.

Making rock candy is easy—it only requires sugar, water, and patience. But if you don’t get your proportions right, you’ll be stuck waiting for crystals to form until the end of time. And that’s just sad.

Time: 30-40 minutes of prep, then up to two weeks of waiting

Difficulty: easy

What you’ll need

• 2 ½ cups of sugar
• 1 cup of water
• A pair of chopsticks (or any thin wooden stick)
• 2 (12-ounce) mason jars (or any heat-proof glass container with a similarly wide opening)
• Clothespins
• Paper towels
• (Optional) Food coloring of your choice
• (Optional) Food flavoring of your choice

Instructions

1. Bring the water to a boil . Needless to say, this step should be performed by an adult to avoid any burns. Once the first bubbles start to appear, turn the heat to low.

2. Pour the sugar in to create a supersaturated solution. Do it slowly and keep stirring until all the crystals have dissolved. Eventually, you’ll feel like you’re inhaling some of the sugar in the steam—keep going. They don’t call it supersaturated for nothing.

• Note: The amounts of water and sugar in this formula will be good for two rock candy sticks. If you want to make more, increase the quantities, making sure to maintain the same 2.5-to-1 ratio of sugar and water. This, as you’ll see later, is crucial.

3. Let your solution cool down to room temperature. You can leave it in the pot or pour it directly into the mason jars. Moving it to the jars will accelerate the cooling process.

4. (Optional) Add color and flavoring. If you want to give your rock candy some color, put a couple drops of food coloring into the solution and stir. How much you use will depend on how vibrant you want the color to be. This is also the time to add flavorings. Again, how much you use will depend on how intense you want the flavor to be.

• Note: If you want each piece of candy to be a different color or flavor, pour the solution into your mason jars and add the attributes of your choice to each one.

5. Wet your sticks. Separate your chopsticks and put them in a glass of water. How deep you’ll need to submerge them will depend on the size of your mason jars and the amount of solution you made. For 12-ounce jars, dunk your chopsticks up to a third of their length. Then, take them back out.

6. Dip the wet ends of your chopsticks in sugar. Pour some sugar on a plate and roll those sticks around in it. Make sure they pick up as many crystals as possible.

7. Let the chopsticks dry for a couple minutes. If you can, place them on top of something so the sugar-covered end stays in the air.

8. Prep your mason jars. If you haven’t already, pour any food coloring and flavoring into the mason jars and fill them with the sugar solution. Make sure each jar has enough to fully submerge the sugar-coated ends of your chopsticks. You won’t need the lid, but if it helps, twist the band shut to make the opening smaller.

9. Put one chopstick in each mason jar. The sugar-covered end should be totally submerged. Hold the clean end with your fingers and make sure the stick doesn’t touch the bottom or the walls of the jar. If it does, crystals will grow between the wood and the glass and good luck trying to get your candy out later. Secure it in place with a clothespin. Repeat this step for the second jar.

• Note: This is why the size of the jar’s opening matters. If it’s too wide, the clothespin will fall into the solution and the chopstick will rest against one of the sides of the jar. You definitely don’t want this. If you can’t find clothespins big enough, you can use two. We even tried tying a piece of yarn to the chopstick and keeping it in place by pulling it tight and securing both ends with the band. Reaching a balance is tricky though, since the chopstick will tend to lean to one side of the yarn, but it’ll do the trick in a pinch.

10. Cover your jars with paper towels. This is just to make sure nothing funky falls into your jar and gets fossilized in the sugar . Fold the paper towel in two and, using scissors, make a small cut in the center to put the chopstick through.

11. Wait. Growing rock candy is a slow process. You’ll start to see some crystals by day two, but they will reach their peak growth after two weeks.

12. Get your candy. Whenever you’re satisfied with the size of your rock candy, feel free to release it. Using a spoon, break the sugar layer on top and move the chopstick around to get it out. If for some reason there are crystals attaching the stick to the jar, an adult can use a knife to chisel it out carefully.

How it works

Water’s ability to dissolve sugar changes with temperature. That’s why if you pour two packets of sugar into a cup of hot tea, the crystals dissolve almost immediately. If you put it in a cup of iced tea, though, some crystals will sink to the bottom.

At room temperature, water is only capable of dissolving around 67 percent of the sugar you pour into it—that specific saturation at that particular temperature is thermodynamic equilibrium.

“When the concentration is less than 67 percent, any crystals you add to the solution will dissolve trying to reach thermodynamic equilibrium,” explains Richard W. Hartel, a food engineering professor in the food science department at the University of Wisconsin-Madison.

Room-temperature water with a sugar concentration any higher than that makes a supersaturated solution. We need that type of high concentration to grow our crystals. But in order for so little water to dissolve such a large amount of sugar (2.5 cups!) we need to boil the water first.

When the solution cools to room temperature, its sugar concentration will remain the same as when it was boiling—approximately 75 percent. At that point, sugar molecules in the solution will try to reach equilibrium by lowering the concentration to 67 percent. They do this by going back to their original state.

“In liquid form, the sugar molecules have a lot of energy as they bounce around. But when constrained in a crystal lattice, their energy is low,” says Hartel.

The sugar on your chopsticks makes it easier for crystals to grow around them, but (as you’ll see) they’ll also form on the walls of the mason jar and even on the very surface of the solution.

After about two weeks, when the sugar concentration has reached 67 percent, crystals will stop growing and your rock candy will be as big as it can be. Chisel those crystals like you’re unearthing an ancient treasure, and enjoy.

Latest in Projects

How to start growing herbs in your kitchen how to start growing herbs in your kitchen.

By Debbie Wolfe

Going off-roading in a DIY’ed Porsche Taycan (yes, a Porsche) Going off-roading in a DIY’ed Porsche Taycan (yes, a Porsche)

By Kristin Shaw

Make Your Own Rock Candy

by Science Explorers | Oct 16, 2017 | Blog | 0 comments

*Please note parental participation is required for this experiment due to working with scalding liquids.

Can a single science experiment be alliterative, fun and yummy all at the same time? When it comes to making your own rock candy, the answer is absolutely!

Involving words like “solutes,” “solvents,” “sedimentation,” “solutions” and “supersaturated,” talking about making rock candy obviously fits the bill for being alliterative. It also requires the involvement of both adults and children, so making rock candy is a fun activity for all ages.

And since the final product has “candy” in its name, making rock candy is sure to produce a tasty treat at the end of the experiment.

What You’ll Need

To pull off a rock candy experiment for kids, you’ll need to gather a few supplies. Here’s what you’ll need to get together ahead of your experiment:

• Three cups of granulated sugar
• One large glass container
• One smaller glass container
• One cup of water
• One heavy spoon
• Paper towels
• String (clean, preferably new)
• Food coloring (optional)

Since you’ll need a heat source for your rock candy science experiment to work, it’s wise to set up shop in your kitchen near your stovetop or microwave.

How to Make Rock Candy

Once you’ve gotten the ingredients and tools necessary to make rock candy together, call your kids into the kitchen because it’s time to get started! Here are the steps you and your children should follow to make rock candy successfully:

• Pour three cups of granulated sugar into your glass container.
• Add one cup of water to the sugar and stir. The chemistry already begins at this point of the experiment. Instruct your kids to watch the water as it makes its way through the sugar. Explain that the sugar is a solute, the water is a solvent and that together, they’re forming a solution. You can also talk about how the solution is thick or viscous because there’s significantly more sugar than water in the container.
• Once it’s stirred thoroughly, the solution must be heated until it boils. You can use a microwave or your stove to warm up the solution. Reminder: It’s advisable for an adult to handle this step to prevent any little ones from getting burned.
• When the solution is returned to a heat-safe counter or tabletop, stir it again and let the kids see how heat has changed the mixture.
• Heat the mixture for another two minutes without letting it boil over, and then stir it again. Point out that the solution is now less thick than it was prior to you heating it up.
• If you’re using food coloring, add some to your solution. Be sure the color of the mixture is pretty dark to produce the best end result.
• Pour the solution into the smaller glass container.
• Tie a piece of string to the middle of your pencil and cut the string so that it’s two-thirds the length of your small glass container. It’s important to use clean string, which is why it’s advisable to use new.
• As your child holds the pencil, have him or her lower the string into the solution until the string is soaked through.
• Once the string is fully soaked, lay the pencil and string on wax paper so they make what looks like a cross (i.e. the string should be perpendicular to the pencil).
• Let the solution cool down and let the string dry out.
• When your solution reaches room temperature and your string is completely dry, suspend the string in the solution by laying the pencil over the top of your container so it can work as an anchor.
• Cover the top of your container with some paper towels and put it in a location where it can stay put for about a week.
• Take a look at your solution from time to time and see the crystals that have formed along the sides and bottom of your container and your string.
• At the end of the week, use the pencil to remove the crystal-covered string from the solution.
• Enjoy your rock candy!

The Science Behind Rock Candy

When you heated and stirred your sugar and water solution, you made what’s called a “supersaturated solution,” which had way more solutes than your solvent could dissolve at room temperature. Since you heated the solution, the water was able to dissolve the sugar faster because water molecules move quicker when they’re heated. As your solution cooled, the solutes remained in your mixture even though your supersaturated solution contained more sugar than the liquid could reasonably handle.

Over time, the sugar solutes fell out of your solution as particles or precipitate. As they did, they connected with other particles to form a crystal, which is your rock candy.

After-School Science Clubs

If your children enjoyed making rock candy, they’ll love the fun experiments we do every day during our  after-school science clubs . Our educational clubs are open to children ages 4 – 11 across parts of Pennsylvania , New Jersey , Delaware , Maryland , New York and Virginia.

Recent Posts

• How to Explore Science at the Playground
• Guide to Funding a School STEM Program
• 5 Earth Science Experiments: Safe, Exciting and Educational
• Beach STEM Activities
• Guide to Sports Science for Children

Recent Comments