Edible Science: Rock Candy {Tutorial}



Rock candy is always a fun favorite of children, and it’s a fantastic way to disguise a Summer science lesson as a sugary treat! All it takes is a few simple tools, lots of sugar and even more patience!


Rock candy ingredients & supplies: Wooden skewers (cut in half), water, sugar, clothespins and glass jars/drinking glasses. The amount of water and sugar you need depends on how many pieces of rock candy you would like to make and the number of jars you have available (I recommend no more than 2 pieces per jar) – the standard ratio is 2 cups of sugar to 1 cup of water, but we found that we had to add a bit more sugar than our recipe called for. In the end, we used 10 cups of sugar to 4 cups of water.



To make our batch of rock candy, we started with 4 cups of water and 4 cups of sugar. Put it all into a large saucepan, because once you put it on the stove it will expand while boiling. I let Sutton mix up the first bit of sugar before putting it on the stove. He was fascinated with watching the sugar dissolve, and it was especially interesting for him to see that we could dissolve even more sugar with the addition of the heat from the stove. Once your pot is on the stove, bring it to a low boil over medium heat, and continue to add sugar one cup at a time until you can no longer dissolve any more of it (making a completely saturated sugar solution).


Turn off the heat and allow it to cool for 15 minutes.


While your sugar is cooling you can prep your sticks. Soak them in water and roll them in a coating of sugar to give the new sugar crystals something to “seed” to. Be sure to let them dry all the way! If they are still too wet when you put them into the hot sugar solution, all of the sugar coating will fall off, and the new crystals will have nothing to grow on.


CAREFULLY pour your sugar solution into your glass jars. If you’d like to add food coloring or flavoring to your rock candy, now is the time to do so. We added color, but we kept the flavor all natural (what kiddo doesn’t like the taste of plain sugar?).


Slowly insert your sugared skewers into the solution. You can use a clothespin as shown to keep your sticks in place. Smaller mouth jars/glasses work best, but only allow room for about two sticks per jar. Be sure that your sticks are not touching the sides or bottom of the glass or each other! They need room for the new crystals to grow!


Set them up in a warm, sunny location where they won’t be disturbed, and wait…


…and wait…and wait…and wait (still with me?)…and wait some more…


After about a week you will have made yourself a batch of sparkling sugar rock candy!




So pretty, so tasty and sooooo worth the wait! These would make fantastic holiday gifts to go along with tea or coffee sets (is it crazy that I have Christmas on the brain in July?)!



  1. says

    Love this! I’ve seen it before, but you just saved our boring Friday tomorrow. My boys will love doing this and watching them grow!

  2. says

    OMG – I LOVE this! I was seriously JUST looking for a recipe for rock candy because I was thinking about making some because it just seems like the perfect summer treat! I love it and am crazy impressed with your science lesson AND your giant assortment of colors! : )

  3. says

    Oh, I forgot how simple and fun these are to make! I think I’ll make a batch with my students next year when we study physical properties. Thanks for the tutorial!

  4. says

    I am sooo excited to try this with my kids. They will think I’m SuperMom, which is what I’m going for, actually, so thanks so much for the tutorial! I’m your newest follower!

  5. says

    I’ve been enchanted by rock candy since I was a little kid — this is WONDERFUL! I’m so glad I saw your post featured over on the Homework blog. I can’t wait to try this with my girls!

    New follower and fan,
    Jenn/Rook No. 17

  6. says

    I tried making this once and they were an epic fail. I think the seeding is key! Great tutorial and photos…I’ll have to try them again!

  7. says

    @Janice, the seeding is definitely the most important part! We actually had to start these over again since the seeding sugar didn’t stick the first time (wasn’t totally dry when we put it in the hot sugar liquid), but the second time around worked like a charm! :)

  8. says

    Trying to make these today. I hope the fact that it’s cooler in the house now won’t hinder the progress. The top of the jars did start crusting over, so I’m afraid we’re headed for the same problem that CAB mentioned above. But we’ll wait and see.

  9. says

    What a great idea:) I am always looking for new candy ideas and this is so pretty, I cant wait to make these for my Christmas baskets. The color seems a little pastel though. I wonder if adding more color would give a denser color (I’m thinking for Christmas, red and green. Have you experimented much with your color density?
    Great Tutorial:)
    MamaZinga @ http://ceeceescrazyworld.blogspot.ca/

  10. says

  11. Anonymous says

    Oh, I was so excited to stumble on your tutorial for these. Want to make some for upcoming baby shower-sure hope it works. Loved your paper lantern directions too!
    Thank you so very much!

  12. says

    I’m going to make a bunch of these for my daughter’s birthday party in a month, I should start now incase I mess it up lol!! ThANKS FOR THE POST! i GOT YOU OFF OF i AM MOMMA HEAR ME ROAR. And you will be on mine next!

  13. says

    Please explain what to do when you remove them from the jar. Will they still be wet? Do you lay them out to dry? Wrap them? HELP! It seems the rest of the instructions are missing……..

  14. says

    Mar, I had to wiggle the sticks gently in the container to loosen them as there will be a thin layer of crystallized sugar on top of the remaining liquid. I held the sticks above the containers and let the excess sugar liquid drip off for a moment and then set them on a sheet of waxed paper to dry. They dry quickly, and are ready to eat right away. To store them, I put them in a Ziploc bag, but they didn’t last very long around here! :)

  15. says

    I would like to take the opportunity to thank you for this post. It made my heart skip a beat. Not until I saw this did I remember that my mom used to do this with us 45 years ago. She has been gone for 35 years now, and my kids are all grown…..BUT I have grandkids, and my youngest daughter works in a day care center so she would love this. Anyway- Thanks for the memories…………oh ……and the wonderful tutorial!!

  16. says

    Couldn’t you make it with another liquid instead of water…..maybe that’s how you could get a different flavor. Not sure,but an idea.

  17. says

    Couldn’t you make it with another liquid instead of water…..maybe that’s how you could get a different flavor. Not sure,but an idea.

  18. says

    Couldn’t you make it with another liquid instead of water…..maybe that’s how you could get a different flavor. Not sure,but an idea.

  19. says

    Couldn’t you make it with another liquid instead of water…..maybe that’s how you could get a different flavor. Not sure,but an idea.

  20. says

    Ivory, I do believe that covering the tops will effect the evaporation process. I’m not sure if it would stop the crystals from forming completely, but it might result in smaller candies. Let me know if you do try it!

    • Rachel says

      We used to have an ant problem. If you put the glass jars in a shallow dish or pan with a shallow layer of water, creating a “moat”, the ants won’t go near it-they can’t swim. I don’t think it would hinder the crystallizing process. Great post!

  21. says

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  22. Buffy says

    What a FUN and SWEET treat to make. I know some people who are learning Patience, and this project has such a nice ending! Candy that is homemade is always the best too! Thank You for the great instructions!!

    • says

      Since the rock candy is water based and requires that the mixture sit undisturbed for several days, I’d be worried that an oil based flavoring would separate during the process. I’d personally stick to extracts just to be safe. If you do try the oil, please come back and let me know how it worked out for you! :)

    • says

      Thanks, Kisha! Honestly, I have never tried to reuse the solution again, so I’m not sure how well it would work. It may take a little longer the second time around since some of the sugar has already been removed from the liquid, or you may end up with smaller pops. If you give it a try, I’d love to hear how it works! :)

  23. Sarah says

    This is a wonderful tutorial. Do you happen to know how long you can store them? I was planning on making them for my daughters birthday party and was trying to figure out how far in advance I could make them

    • says

      It will keep practically forever as long as you keep it dry and away from heat! Since it’s just sugar, if you store it in an air-tight container it will last for years!

  24. Sarah says

    Talk about being left hanging! There was no mention of what to do or how to do it regarding the correct way to remove the sticks from the jar!! Do u just pull the sticks out after a week? Can u please finish the directions on the recipe??!!

    • says

      Yes, you simply lift the stick out of the jar when it has reached the desired size (after about a week). If you find that the sugar has formed a crystallized layer on the top of the liquid, gently move the end of the stick from side to side to break up the top layer, and then it should just come right out.

  25. Sarita says

    I will be taking care of grands three days a week this summer. Ages 5 and 7… Will start the rock candy the first day they are here. We can watch it grow over fee weeks….what fun! Thank you…

  26. says

    This delicious candy is actually crystallized sugar and you can “grow” it from a sugar-water solution. I agree it’s a fantastic way to disguise a Summer science lesson as a sugary treat!

  27. Jessica says

    I’m making these with my science obsessed son for his birthday party. He loves the idea of growing his own candy to give his friends!! My question- how many pops did you get out of the 10cup batch? I’m trying to figure out how much materials we need! Thanks

    • says

      Hi Jessica! We only got about a dozen of these because each jar that we used (6 in total) only fit 2 sticks at a time inside. The sticks need to have space around them for the crystals to grow, so you don’t want to overload the jars. :)

  28. Jordan Johnson says

    HI, we are doing this for a science project and our seeding didn’t work…all the sugar disolved right off even after letting the sticks dry for a good 30 minutes. Do you think we need to start ALL over or can we just put new seeded sicks into the same liquid?

    • says

      Hi Jordan, I have had to start over once before, and I used the same liquid with new seeded sticks, and it worked just fine! Good luck! It can be a little finicky sometimes, but it’s really rewarding once you get the hang of it! :)

  29. Ariel A. says

    I saw this on pinterest and thought “Wow! I need to know how to make this!” They were more simpler than I thought.

  30. Bridget says

    Hi!! I love this! We are adding it to our summer bucket list. I know this is an older post, however I was wondering how long the sugar stick needs to dry for? It says make sure it is all the way dry. I was wondering if I should have the sticks dry before I invite the kids over.
    Thank you so much

    • says

      I would make the sticks up on the morning of your play date. They take about 1-2 hours to dry (but I generally leave mine to dry overnight), so making them up just a couple of hours ahead of time would be fine. :)

  31. Simeren Silverstein says

    This looks so fun! How much syrup did you get out of the 10 cups of sugar and 4 cups of water? How high did you fill the jars?

  32. says

    This looks amazing!!
    Just one question: Which colours did you use to make the mint green rock candies?? And do they get bigger the longer you wait?
    Thanks! :)

    • says

      I used regular green food coloring for the mint green candies, but I only used a small amount of it. The sugar crystals continue to grow for about 7-10 days in the jar, but after the sugar in the liquid has all crystallized on to the sticks it will stop growing.


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