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.
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!
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).
How to Make Rock Candy
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!).
Have you ever made your own rock candy at home?
DIY Rock Candy
- 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
- 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.
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