Even if you don’t have a big outside yard area, your child can grow potatoes in a plastic bag—easy to grow and harvest, and yummy to eat! This simple food science project will help satisfy your kid's curiosity about how pants grow...and satisfy his hunger once the potatoes grow!
Disease-free seed potatoes (from garden stores) or grocery store potatoes
Compost and soil
What You Do:
Place two potatoes in a warm spot and give them a week or so for sprouts (“eyes”) to form. Let the sprouts get to be about ¼ to ½ inch in length.
If the potatoes are larger than a chicken’s egg, help your child cut them into chunks about 2 inches wide. Each chunk should still have at least two sprouts. If the potatoes have been cut, let them sit a few more days before planting.
Roll down the sides of your large garbage bag (make sure it’s black to keep the heat in) to be about half its original height. Use scissors to help your child make some holes in the bottom of the bag for drainage. Put the bag outside in a sunny area that won’t gather frost.
Your child can shovel in 2 parts soil to 1 part compost to fill the bag up to about 12 inches.
Next, your child can plant the potatoes or potato chunks. He should put them in the soil with the sprouts pointed up. He should shovel in another 5 inches of soil/compost mixture to bury the potatoes. Then he can water them.
Within three weeks, your child should see shoots coming up inside the bag! Keep the soil damp but not soaking. When the shoots are about 6 inches tall, roll up the edges of the bag a bit and add more soil/compost mix so that just the leaf tops show through dirt. Continue this process every few weeks until the shoots reach the top of the bag and start to flower, about 70-90 days from planting. Water the potatoes less often in the last week of time.
To harvest, help your child cut open the side of the bag. Ta-da! Potatoes for dinner!
Beth Levin has an M.A. in Curriculum and Education from Columbia University Teachers College. She has written educational activities for Macmillan/McGraw-Hill and Renaissance Learning publishers. She has a substitute teaching credential for grades K-12 in Oregon, where she lives with her husband and two daughters.