Green onions (also known as spring onions or scallions) are one of the easiest vegetables to grow from scraps! This guide will teach you everything you need to know about how to grow green onions indoors from kitchen scraps!
I am a huge fan of reusing kitchen scraps. After making our lemonade concentrate, I used the peels to make an all-purpose cleaner from the lemon peels and vinegar! As well as chicken broth, and beef bone broth, both from scraps!
How to Grow Green Onions Indoors From Scraps
When you purchase fresh green onions from the grocery store don’t throw the root end away! You can grow a steady supply of green onions right from home.
Cut the onion: Cut the onion just above the white portion of the green onion plant and use the green part for your favorite recipes. I’ve cut right past the white stalks and still have success with new growth!
Put the roots in water: Grab a glass of water and fill it just so the water level is covering the roots. Leave about an inch of the white part out of the water.
Find a sunny spot: Place the cup of water with the onion roots in full sun. A sunny windowsill (preferably a south-facing window) is the best way to regrow these young plants.
Refresh the water: About once a week or when the water starts to become foggy dump the old water and add enough water to cover the white bulbs. Adding fresh water helps avoid root rot and encourages green shoots to start growing.
How to Harvest Green Onions
Harvesting onions on your windowsill is easy! Simply cut the number of green onions you would like, or use the whole plant! Remember to place the roots part back in the water for more green onion leaves!
How Long Do Green Onions Last in a Glass Jar?
Green onions can last months and even up to a year by regrowing in a glass jar. As the months progress, you may find that the flavor of the onions starts to become mild. The good news is you can plant the onions in the garden at this time or go out and buy more bunching onions to regrow for another year!
How to Transplant Your Green Onion Plants to the Garden
I’ve had success with planting just the white bulb in the garden as well as starting in a mason jar full of water before planting in the garden. I will discuss both ways with you.
Planting Green Onions in the Garden From Scraps
Cut the green onions: Start by cutting off the green part of the onions, leaving about an inch of the white part attached to the roots.
Prepare a planting bed: Choose a location in your garden that receives plenty of sunlight and has well-draining soil. Loosen the soil to a depth of 6-8 inches and add compost or well-rotted manure to the soil.
Plant the onions: After your last frost date, make a small hole in the soil and insert the onion scraps with the white part facing down. Space the onions about 2 inches apart.
Water the onions: Water the onions thoroughly after planting to settle the soil and help the roots establish.
Maintain the onions: Ensure regular watering to maintain the soil moisture but not too much or you will have soggy soil, resulting in root rot. Green onions grow quickly and should be ready to harvest in 3-4 weeks.
Harvest the onions: Harvest the green onions by cutting off the green tops with a sharp knife or scissors when they reach a height of 6-8 inches. Leave the roots in the soil for continuous harvests.
How To Transplant Green Onions From a Jar Into Garden Your Garden Beds
Similar to the steps above, cut the green onion, but instead, put them in a jar of water. In a few weeks, you can plant them in the garden to continue growing green leaves and form new green onions!
How to Grow Green Onions Indoors From Seed
Growing green onions from seeds indoors is a relatively easy and straightforward process. You can start your seeds in late winter and plant them outside during the growing season. Many garden centers don’t carry green onions, but you can find many types of onions online in seed packets and onion sets.
Choose a container: You can use a small pot, a plastic container, or even a recycled container, with good drainage. I like to use those plastic clamshells that strawberries come in.
Fill the container: Fill the container with organic matter such as good quality seed starting mix, leaving a half-inch space at the top.
Sow seeds: Sprinkle the green onion seeds on top of the soil and gently press them down. The seeds are small, so it’s okay if they are close together. Sprinkle a thin layer of soil on top of the seeds, enough to cover them.
Water the soil: Water the soil thoroughly from the bottom, but make sure not to overwater. You should be able to feel moist soil from the top but not soaking wet.
Cover the container: Cover the container with plastic wrap or a clear plastic lid to create a mini greenhouse effect.
Place the container in a warm, sunny spot: Place the container in a warm, sunny spot, preferably near a window with lots of natural light. To provide your green onion seedlings with optimal light, I suggest investing in a grow light and seedling heat mat. Check out our indoor seed starting setup to see how we start all of our garden seeds successfully! Green onions need a minimum of 14 hours of sunlight, using a fluorescent plant light ensures they are getting the proper light they need.
Remove the cover: Once the seeds have germinated, remove the plastic wrap or lid and continue to water the soil as needed.
Thin the seedlings: This is optional, but once the seedlings have grown a few inches tall, thin them out by removing some of the weaker ones. Since green onions have a shallow root system, I have had success skipping the thinning process. The only seedlings that I thin are the ones that are touching. This helps avoid the new plants from competing with one another.
Fertilize and Care: Once the seedlings have started growing, it is important to start fertilizing them once a week with a balanced fertilizer. I have had huge success with this fish emulsion for all of my seedlings and garden.
Liquid Fish Emulsion Fertilizer
The best organic fertilizer for a healthy and thriving garden!
Transplant the seedlings: In early spring when the seedlings have grown to about 3 inches tall, after hardening off, transplant the green onion plants into a larger container or outdoors in the garden with rich soil a couple of inches apart (2 inches). Finish will a layer of mulch to maintain the soil moisture.
Other Gardening Posts:
- How to Grow Peppers From Seed Indoors
- How to Grow Radishes From Seed
- Our Indoor Seed Starting Setup
- How to Plan a Canning Garden