Waste not, want not: turn kitchen scraps into healthy food

Written by Rita Heikenfeld, local culinary educator, herbalist, and journalist

Have you ever grown a sweet potato vine or avocado pit in water? If so, then you can consider yourself a hydroponic gardener! When we were young, my mom would take a sweet potato past its prime and use toothpicks to suspend it in a jar of water. After a few days, tiny, hairy roots started working their way into the water. She wound up with a beautiful vining plant and trained it to grow around an entire window frame. 

I’ve done the same for many years. And not only with sweet potatoes. Green onion roots, celery, and lettuce bottoms can all find extended life growing in water. Leftover dry lentils spring to life as nutritious sprouts in just a few days when placed in water.

These days it’s trendy and practical to take up some of these old fashioned ways of stretching the food budget.

“Waste not, want not” has become the new mantra during these challenging days of sheltering in place. The grocery stores that used to be open 24/7 have limited hours, limited inventory, and sometimes limit the number of customers in the store. Couple that with folks not working, and you’ll understand why many of us are being creative and using every edible part of food items, especially with produce. 

And you know what? It’s fun! Get the little ones involved and they get a lesson in food science and an awareness of how to be good stewards of our environment. 

The Basics

Room temperature, good quality water should be used. 

Sweet Potatoes

There are several ways to re-grow sweet potatoes. Basically, you want the bottom of the potato to be in the water.
Poke toothpicks into the top end, place in a jar or glass, and fill with water to reach the bottom of the potato. You can also put the potato in a jar or cup large enough to hold it upright without toothpicks. Or, lay the potato in a shallow pool of water.

Place in a sunny window. 

Be patient. Sweet potatoes take a while to sprout, but once they start, they grow fast! Change the water as necessary.


Use toothpicks to submerge the bottom half of the avocado pit into a glass or bowl of water. 

Place in a sunny window. 

Watch it grow! 

Lettuces, Celery, and Green Onions
Lettuces and green onions are super easy to re-grow. Simply place the bottoms root ends in a bit of water. Change water daily. Soon you’ll see growth coming out of the middle of the core or onions. 


I love sprouting lentils! They take a bit more attention.

Put about 1 cup dry lentils in a quart or larger jar. 

Add 2 cups water, and cover with a cheesecloth, or coffee filter secured by string, sealing ring or rubber band. 

Let sit overnight. This helps germination.

Drain water out, replace the cover and let sit on the counter either upright or on its side, away from sunlight. 

Every 12 hours, add water, stir the lentils around a little, then drain it off. Do this until you harvest the sprouts.

You’ll see little tails on the lentils sprouting after a couple days. Soon after that, the growth will be even more obvious. It will look like the sprouts have grown green hair! Give them another gentle rinse in a colander and enjoy.

Refrigerate up to 2 days.

You can follow Rita Heikenfeld on her blog About Eating, opens a new window and on her YouTube channel, opens a new window.