Make homemade rock candy with these tips and tricks and answers to frequently asked questions. A fun science experiment and treat for kids! Rock candy takes 5-7 days to grow, but the process is fun to watch!
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With kids out of school earlier than planned this year we decided to make rock candy again! We’ve updated this post with new photos and a video from our most recent batch of rock candy. Like last time, we made A LOT of jars of syrup. Like 8 cups of water and 20 cups of sugar worth. That fills 12 small jars. You DO NOT need to make this much. As long as you keep the ratio the same it will work the same! Our rock candy crystals have come out in varying sizes over the years. There are a lot of factors that come into play, but regardless they taste delicious!
Grab a bag of sugar out of your pantry, a few wooden skewers or rock candy sticks (cotton string works too), empty jars, and food coloring and let’s get started!
Homemade Rock Candy is easy to make, it just takes patience.
There are so many variations using string, sticks, etc. It’s a beautiful science project and sweet treat all in one. It does take time, and the end results can vary. There’s a science to it and that’s all part of the fun! Just know this… YOU NEED A WHOLE LOT OF SUGAR. A LOT. You can start with a 1:2 water/sugar ratio, but we’ve had better luck just shy of a 1:3 water sugar ratio. So if you have 4 cups of water, you’ll need between about 10 cups of sugar to make the perfect sugar syrup.
Scroll to the bottom for some frequently asked questions for making rock candy.
How to Make Rock Candy on a Stick
Homemade Rock Candy Recipe
Make homemade rock candy with these tips and tricks and answers to frequently asked questions. A fun science experiment and treat for kids!
4.12 from 18 votes
Print Pin Rate
Cook Time: 30 minutes minutes
growing time: 7 days days
Total Time: 7 days days 30 minutes minutes
Servings: 6
Calories: 50kcal
Cost: $5
Equipment
funnel
glass jars
clothespins
large pot
Ingredients
- Sugar lots of sugar
- Water
- Food Coloring concentrated for brighter colors
- Wooden Candy Sticks or Bamboo Skewers
- flavoring optional
Instructions
Trim down your skewers to a reasonable size to fit in whatever jars or cups that you will be using. You'll also want to get rid of the point. Dip them in water, then roll in sugar.
Let the sticks dry completely and set aside. This will give the sugar a base (something to stick to when it starts to crystallize).
Heat water on medium-high heat. When it starts to simmer/boil begin adding sugar until you reach a 1:2 to just shy of a 1:3 water sugar ratio. The mixture will take longer to dissolve the more sugar you add (totally normal). Keep stirring with a wooden spoon until completely dissolved. Remove from heat. CAUTION: it is very HOT!
Ladle the syrup into your jars using a funnel to catch spills. Add food coloring and flavorings to each jar, if you’d like wouldn't grape, cherry, orange or lemon flavoring be delicious?).
Allow the syrup in the mason jars to cool down a bit. Warm or room temperature. Attach a clothespin to each skewer (the ones you dipped in sugar and let dry) and place in the jar.
Place your jars in a safe location and watch the crystals grow!
Notes
- You can create as much or as little syrup as you'd like as long as you keep the same sugar/water ratio. You are making a nice, sticky, sugary syrup.
- If after 24 hours you don't see any crystal growth, pour each jar of syrup back into the pan (separately) and add more sugar. 1/4 c. or so and heat once more until it is a syrup consistency. Roll the sticky skewers in sugar and add once more to the jar after the syrup has cooled down to be warm (not hot) or room temperature.
- Make sure the skewer isn't touching the bottom or sides of jar/glass. They need room to grow. One skewer per jar works best for regular sized jars.
Nutrition
Calories: 50kcal
Day 2. You may notice sugar crystals forming along the bottom of the jar, (most likely from any sugar solution that didn’t dissolve all the way and is settling at the bottom) and there will be a crust on the top surface.
After 5-7 days you can eat your rock candy! Allow the syrup to drain off then set the rock candy on a baking sheet to dry.
Our beautiful blue rock candy broke as we pulled it out of the jar. I accidentally had the stick too close to the bottom, and the crystals attached to the sugar residue growing on the bottom. It was the only blue jar we had, everything else was red, yellow and green! Oh well.
We had a great time watching them grow and sampling the finished product. We’ve made rock candy a few times and it is generally ready to pull from the syrup between day 5 and day 7. I’ve seen others recommend allowing the sticks to sit for 1-2 weeks. Just pull them out when they are to your liking. My kids are always anxious to eat them as soon as they can!
Frequently Asked Questions:
Can you make more than one stick of rock candy in each jar?
If you attempt to do more than one skewer/jar, use a wide mouth jar.
How do you drain the rock candy?
Hold the lollipop over the jar or paper towels to let most of it drip off and then set it on a cookie sheet to dry.
There will be crystallized sugar in the bottom of your jars/glasses. Just run them in hot water and chip it out with a butter knife.
How long will rock candy last?
The shelf life for rock candy, if kept in a dry location, is 1 year.
Can I use a disposable foam cup for making rock candy?
Nope. It has to be glass, and it’s easier to watch the crystals grow in a clear glass jar!
Why didn’t my rock candy grow crystals?
If crystals don’t grow it is almost always due to lack of sugar.
If after 24 hours you don’t see any crystal growth, pour the syrup back into the pan and add more sugar. 1/4 c. or so and heat once more until it is a hot syrup consistency. Only pour and heat one jar at a time if you used different colors of syrup. Roll the sticky skewers in sugar and add once more to the jar after the syrup has cooled down.
Is this frustrating to do? Yep. I know, because I’ve done it before!
Can you re-use rock candy syrup to make more crystals?
This is probably the most asked question that readers have e-mailed me over the years. I have not tried to re-use the syrup, but I don’t see why you couldn’t add another stick (covered in dry sugar) into it and grow another more. It might be worth reheating it to test and make sure that it is still saturated, but you have nothing to lose except a bit of time.
Should You Cover Your Rock Candy Jars?
I had no fear of insects or little fingers messing with them so I did not cover mine.
Here’s are a few more tips for making homemade rock candy:
- Make sure your glass/jars are clear and CLEAN.
- Make sure your water/ sugar ratio is AT LEAST 1:2- just shy of a 1:3. You want a thick, saturated sugar syrup mixture.
- Place in a WARM, SUNNY location if you’d like to grow crystals quicker. They will be smaller crystals. If you want larger crystals, place it in a place away from direct sunlight. Our crystals are small because we grow ours on a windowsill. We like seeing the light shine through the glass and watching the crystals grow.
