Rock Hill Coca-Cola Blog

Icky Petri Dish Halloween Treats

Halloween season is upon Rock Hill again! It’s time to start planning the spooky fun for all the ghosts, goblins, ghouls…and mad scientists out there. These Icky Petri Dish Halloween Treats are just the right kind of deliciously off-putting. Kids will love the gross out factor and parents will love the ease. 

Dishes Make the Dish

Although you can mix these gruesome concoctions in any old bowl, making them directly in a petri dish drives the icky home. Do it right and they really will look like a forgotten experiment…or one gone horribly wrong! A quick search online will find relatively inexpensive petri dishes suitable for your own little mad scientists.

Flavors and Colors

Any flavor gelatin will work, but a combination of lime green and lemon yellow yields the ickiest color that shows off the other additions to the best effect. Those flavors also pair perfectly with Sprite, which will add a little extra kick to the mix.

Creepy Additions

You can add almost any kind of fruit-flavored candies to the gelatin dish. We recommend gummies: worms/strings, rings, frogs, spiders, bugs. Also, any tiny hard candies will look like bacterial bloom clusters.


  • 3 oz box lime gelatin mix
  • 3 oz box lemon gelatin mix
  • 16 oz (2 cups) Sprite, ice cold
  • assorted candies, small and creepy 
  • optional: medium to large plastic creepy-crawlies for the older kids


Boil water according to the gelatin boxes’ instructions. When the water comes to a boil, add the gelatin mixes. Stir until all the powder dissolves completely.

Remove the liquid from the heat. Allow to cool slightly. Gently pour in the ice-cold Sprite. Stir gently until thoroughly mixed.

Allow the mixture to continue to cool at room temperature while you prepare the petri dishes.

Place the petri dishes on a tray that will fit into your refrigerator. Add candies and decorations to the dishes. Do not overload the petri dishes. A few well-placed items will do the trick (or treat).

Gently pour the slightly cooled gelatin/Sprite mixture into the prepared petri dishes. Adjust the position of the creepy bits as necessary.

Carefully transfer the tray to the refrigerator to cool for a few hours or until the gelatin is firmly set.

Remove from the refrigerator just prior to serving.