Trimming Onions for Bigger Bulbs. A Myth?

Trimming Onions for Bigger Bulbs.  A Myth?

This video concludes an experiment on whether or not one can cut the tops off onions and encourage a larger bulb. I explore that concept with my personal results included.

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What do you think?


  1. Please use Scrolling English Words alongside the Video. It will be helpful for International Clients to Understand the Topic Deeply as we can't fully understand your Accent.

    Subject Very Informative. I understood just by seeing the Video. What you have Spoken I don't understand because of your Accent.


  2. Thanks. I'm here to know if the tops regrow if i cut some off. Where i live we cannot grow onion, just the greens. Now i know i don't need to sacrifice the whole plant if i need just a small handful

  3. You cut low and late
    I would guess the idea is to promote back budding so the bulb gets larger…. I think that this idea would work if you left more green for photosynthesis but still cut enough off to trick the plant into setting more roots.

  4. I only give onions a haircut when they are very young….while they are just seedlings all crammed into the seedling tray. Trim them down to about 6" tall just before setting out in garden bed. No trimming after that!

  5. Planting green onions for fun in a pot because of quarantine. Do the parts of the leaves that bend and fall over from the weight survive and does the plant still need them? And does cutting the part off and eating it harm plant growth?

  6. I trim my onion and garlic plants but that is to harvest greens as I love the greens in salad and just to munch on. It has been my experience that my collecting the greens from the tops of my onions and garlic plants tends to slowly cause them to fail. I seldom ever get much of an onion with that and my garlic cloves stay quite small.

    My kids love to eat the garlic greens and I have trouble with them killing off my garlic patches by eating too much of the greens.

  7. I grow onion sets as micogreens [baby greens?] I find they start out as bulbs, but over time the bulb goes away as I am cutting them. I can cut them for about 3 months, but during this time the bulb just vanishes. After the 3 months, they just shrivel and die. I am growing indoors under lights, but that is what I am seeing. So basically the bulbs just go into stress and once they get overly stressed they die. Maybe cutting once would help, but I am not convinced of that.

  8. I chop the tops because I use them.
    I don't let them get that tall.
    I cut them when the reach about a foot. And cut about 10 inches.
    And they grow back.
    Unfortunately I get 2 to 3 cuts before the critters get to them. So can't tell you if it improves the bulbs.
    I hope to someday harvest the bulbs.
    However, the greens are free onions. Because I use the tops and bottoms from the onions I buy.
    In case someone doesn't know. When you buy onions from the store. If you cut them at about 3/4 inch from tops and bottoms ( green end and root end) and plant them they grow. And yes I said tops also. Plant them top side up, and they grow roots. Cutting them to close and they will not grow. Also I let them start growing greens before I cut them.
    Another thing, is if you just leave them in the bag ( I buy in 3 lbs bags) you can cut them a few times and harvest the greens without doing anything. This includes not watering. Warning about the 3rd time they will not grow anymore and there will be a lot of air in the bulbs. Most the time after this, as in over 90% of the time. Even if you plant them after this they will not grow. I have, very rarely got up to 6 cutting from them. In bag cutting I leave about 2 inches of greens and cut when about 8 inches. So about 6 inches are used. They are pretty strong and thick in flavor like this. Wigth wise they are much bigger then store bought green onion. Each onion will give about 1/4 to 1/3 greens as store green onions bundle.

  9. You cut way too much off it will work if you cut off all leaves that are bent over just below the bend nothing else. Best to check every couple of days prune as needed throughout the bulbing part of the season. Usually only 1 or 2 leaves per plant bend some plants have none try it this year on part of your onion patch you will see results.

  10. I have one fault I've found in this experiment,.. and that is he cut off the baby green lead part,.. I'm thinking he should've pulled it away, down to the last few stalks,.. forcing it to "Grow" more green leaves, that is a bigger onion,..

  11. It's a no go, but I am thinking something.
    The tops that bend over die from the bend. So Try clipping off any bent tops at the bend so no onions have bent tops. If clipped before it withers, the cut off portion could be used as green onions. That might keep them growing longer.

  12. Here's the technique as per Google: 👉🏼Grow the onions until the stalks are about 9” tall, then trim the green stalks in half (so about 4-5” remains of the stalk). Then, let them grow again until they are about 12” tall, then cut in half again to 6”. Do this 3 times, which will force more energy into the roots and will promote larger bulbs.Jan 1, 2010

  13. I realize this is late, sorry..
    First of all, I also ask how much of the stalk are actually yummy to eat. I would only use the green finely chopped for flavor. You can do whatever you'd like with the bulbs, minus the goatee. 😁
    Secondly, I would hope you used the parts you hacked off ? What a waste, if not. I hadn't expected any to start dying off. How unexpected ! Won't go that route again, huh ? 😉
    Finally, why do stores sell green onions with the tiny bulbs, verses rather large one's, like yours ?? I have seen large bulbs in the stores, but I don't believe they are from the green onion plant ?
    Ok, I think I'm done with my questions ! I'd love to hear your take on these things, and anyone else's, as well, please ??
    HAPPY COOKING !! 🍽️🥂

  14. Hi, many good answers on this one. What I`ve been doing is: snip off one  outer frond from each bulb at one time, close to but not too close to the bulb, preserving and encouraging the inner ones to grow on. They`re the ones that bend first anyway. They are a good addition to  mash taters and are full of nutrition. Frankly, in this scenario you showed, the onions were planted too closely and depending upon your watering and the soil structure, you are going to have some die back of greens anyhow.  I have found that, in cultivating shallowly between the rows and bringing the soil up around the young bulbs, not only aerates the soil, but helps the little guys  better support their tops. Chopping off everything undoubtedly injured the onions and forced them into a survival mode, calling on reserve stored food from the bulb, putting a shock into them.

  15. They are suppose to be cut at a very young age (transplant) to promote extra rings and stronger growth, by cutting late you are allowing moisture and bacteria to form and therefore that was what happened. Good video though x

  16. I think cutting your onions was just a cruel joke someone posted on youtube.. When I saw the video, I thought, hey, its on the internet, it's gotta be I lost my 10 x10 bed of onions. They ALL DIED.. !!!
    After doing much research, I learned that onions actually feed off the TOPS. The TOPS store water and nutrients and when there is a shortage of either, the onions will draw water and nutrients from the TOPS.. ALSO… if you noticed when you cut the tops, they were hollow. When it rains, the hollow tops will fill up with water and it will trickle down into the bulb and ROT it.
    SOoooooo. If you wish to destroy your onion crop, CUT THE TOPS.

  17. Great experiment but you are missing one thing. You cut back the onions the wrong way. cutting the head of the onions would introduce water (H2O) to the head and would eventually rotten the center of the onions. FYI…….Cut back the oldest leaves only but fertilize before doing so. Thanks… Happy gardening.

  18. First of all, great looking onions. Secondly, I think you missed the mark on the trimming. Its supposed to be done AS they are growing, not after. Once they have matured, that level up trimming (way too short) will just cause stress, and hinder its growth (as shown). The only effective way to trim, is as they grow from young sprouts. It promotes the new grown of layers, faster, and gives it more time to mature. The lack of nutes going to stalk growth, contribute to plumping up the layers. So in the END you get better results when you start early. But trimming at the end? Seems to me, all you are doing is stopping growth and speeding up curing… in the dirt… which can cause bottom or top rot.



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