Grow Onions From Discarded Onion Bottoms





Introduction: Grow Onions From Discarded Onion Bottoms

This Instructable outlines how to grow fresh onion plants from discarded onion bottoms that would otherwise be thrown in the trash.  You can theoretically create an endless supply of onions without ever having to buy bulbs or seeds, and if you're as big of an onion lover in the kitchen as I am, you'll have a full bed of onions in no time.

3 Week Update:
New roots have formed on the example onion used in this Instructable, and the starts of leaves are forming which can be seen by the two distinct rises at the top of the onion.  This onion will more than likely form two plants just like fully formed example on this Intro page.

4 Week Update:
New leaves are forming above the soil, and it's clear that this plant will be able to be divided.  It has now gone through a hard freeze in its pot sitting on a growing table.

Step 1: Materials

You will need:
  • Onion
  • Clean Knife
  • Cutting Board
  • Starter Pot with Potting Soil (optional)

Step 2: Slice Off Onion Bottom

Chop off the onion bottom with all the roots still intact.  The more of a bottom you leave on, the better.  Try for 1.5"-2" of attached "meat".

Allow to dry for a few hours to a couple days in a shaded, well-ventilated area to allow for callousing.

Note:  You might only need a few hours for callousing.  If the cut portions are dry to the touch and slightly shriveled, it very well might be calloused enough.

Note:  I'm skipping the dry time for this Instructable.

Step 3: Potting

Fill the starter pot 2/3 of the way full and compact.

Create an indentation in the center to cradle the onion bottom and allow for good soil contact.

Cover with 1-2" of soil.

Water as needed.

Note:  You can skip the starter pot if you can't be bothered and plant it directly in the ground.

Step 4: Finish

Once the onion bottom has developed a few leaves, remove from the pot.

Remove old onion scales.

Separate plants as needed by slicing between plants and leaving a portion of the roots attached.  You may have more than 1 plant develop from a single onion bottom.

Replant in a prepared growing bed.

Cut leaves down to 1/3 of the size to allow the bulb to develop.  This might seem harsh, but the onion will regrow those leaves with less stress.

Repeat the process.  Harvest as green onions or fully developed mature onions.

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When you cut the onion bottom off, which end goes in the water - the cut side or the end? So then, when do you transfer it from water to dirt (pot or ground)? Thanks to all who have shared their experiences. I'm hoping that I'll be able to "contribute" some valuable feedback one day. KEEP UP THE GOOD WORK, EVERYONE!!!


Hello there, ricanprincess92. So, I'm just starting out with the gatrdening thing. I cut the bottom off the round, white onion like you have pictured here (but with a little less "meat"). Then I put it in a little bit of water - enough to cover the bottom. BUT!!! I see here that you put it with the cut side down in the water, right? I put the bottom in the water, with cut side up. It's been about a week, and the bottom is sprouting a couple of tiny, white roots. I'm visually challenged, but I just looked again, and it might have a couple of green shoots (WHATEVER!) sprouting up from the center of the old withered, brown leaves. Am I on the right track, or do I have it upside-down??

Never thought about doing this. Going to try it! Thanks.

I've been doing this for a while now. The onion's new growth will always be from the center area of the onion, so you can peel away most of the old grow before you put it into the soil. I also plant the tops of pineapples. Just pull green part off and tear back the bottom half inch of leaves to expose more of the stalk and then stick it in about a half an inch of water for a couple of days. When the roots have grown out to where they could start utilizing the soil, put them in the soil. They are extremely unfussy. I grow them successfully in medium sized containers and I don't even have to water them. I also grow cumin, fenugreek and mustard from my spice cabinet. I have a three year old avocado tree that I grew from an avocado pit. I grow store bought ginger and turmeric as well. Also shallots, celery and of course onions. I'm in an apartment and the plants are all outdoors (except I just brought in my celery, thanks to advice below) and no one complains. The key to success is the quality of the soil. You have to have container mix if you plant in containers, not "top soil". Gardening is soooo rewarding.

Thanks so much for this information. I am dying to try container gardening, and it encourages me that you are doing it successfully here in Florida. I've hesitated to try because of how awful our soil is and I've been unsure where to even buy good soil for container gardening.

Home Depot.

Unfortunately I live in an apartment and have to keep the plants close to the house where they don't get enough sun. :(

I'm in a house and thankfully have space in both sun and shade but my problem is I don't know enough about gardening to know what grows best in which setting. My mama could grow anything, but she's been gone 8 years now and I have a black thumb. :(

No problem learning, just get some library books.

Perhaps you should find a nursery in your area and tell them what you want to do and then take their advice, Maybe start with one or two plants until you get the hang of it.

With containers, the way you know when it is time to water (if it hasn't rained) is to put your finger into the dirt about an inch down. It should feel damp there. If it feels bone dry or almost bone dry then it needs water. Otherwise, don't because you'll over-water it.

In my place, light is also an issue. I re-grow a lot of veggies with an inexpensive gooseneck lamp. Much to my surprise, bunches of basil and cilantro in glasses of water have rooted and grown into vibrant plants

in organic potting soil.