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mulberryknob

Onions bolting....again.

mulberryknob
13 years ago

Last year many of my onion plants bolted before making bulbs. I had two kinds last year and one bolted badly. This year I have two kinds again, and BOTH are bolting. Last year one clump had a lot of too large plants and someone here (Dawn, I think) said that might be the problem. So this year I was careful to pick clumps that had small plants...and I have more of them bolting than ever. I like to eat a few for green onions, but not as many as I need to this year. Could it have been that hot dry spell we got?

Comments (21)

  • p_mac
    13 years ago
    last modified: 9 years ago

    Mine too, Dorothy. I went in on the group order from Dixondale, so I know they were protected up to a certain point. The bunches were, as usual, more than 60 per bunch, so I know after what I gave away, I still planted over 500. So far...about 8% have bolted. I planted them all on Feb. 28. We're enjoying the fresh eating, but soon there's going to be more than we can eat, so I'm going to chop and freeze them to use in casseroles. winter omelets, etc.. That's all I know to do. I'm really hoping that the whole crop doesn't bolt. Surely I'll get some to store for winter! (hope, hope, hope!!!)

    Paula

  • ScottOkieman
    13 years ago
    last modified: 9 years ago

    I seem to remember reading that a period of below freezing weather can cause onions to bolt. I've got some bolting too, but not as bad as last year. I believe it has to do with the onions experiencing warm temps, then below freezing temps, then warm again. They're "fooled" into thinking they have gone through two years and it's time to put up seed heads.

    I just snap off the seed head stalk and leave the onions as they are. They will go ahead and bulb up, but as you know, will not keep. When you harvest them, go ahead and chop them up and put them in the freezer immediately. Keep the others for regular storage.

  • Okiedawn OK Zone 7
    13 years ago
    last modified: 9 years ago

    I'm sorry to hear about the bolting. Some years are just that way.

    Bolting normally is the result of some kind of environmental stress after the plant has reached a certain size. That's where choosing the smallest onion transplants you can find is helpful. Generally, if onions are smaller than the diameter of a pencil when planted, they are less likely to bolt if the right day-length varieties are planted at the right time for your location. Bruce Frazier usually describes it more in leaf count in his monthly newsletters...I think that onion transplants which arrive with 4 leaves are less likely to bolt than those that are larger. I'll find last year's bolting newsletter and link it, because I don't think he's sent one out this year. Or, if he has, I didn't read it.

    The most common cause of bolting in our climate is our erratic spring weather. Once the oniona are growing well and have reached that pencil diamter (1/4") size or have 5 or more leaves, prolonged exposure to cool weather can push them into false dormancy. Then, being biennials, once they resume growing, they behave as though it is their second year and set seeds, hence the bolting.

    Sometimes onions can bolt in response to drought stress too if the drought stress is severe enough that their growth stalls, and once again, they interpret the stall as a dormant period and bolt once growth resumes.

    The way I was taught when I was growing up was that it was very important for onions to get at least 1" of moisture per week every single week without fail, so I take care to water them to ensure they receive that amount of moisture if rain is not falling. I also take care not to overwater because I have more trouble with onions bolting when we have very heavy rainfall, but I think it is really all the same issue...if we have very heavy rainfall that keeps the soil waterlogged for weeks, their growth stalls and then when they resume growing, they interpret their new growth as their second season and set seed.

    Now, one inch of water a week works out pretty well for me in well-improved clay soil that has a pretty high level or organic matter. If you have sandier soil that drains better, it might take 2" a week. The idea is to provide consistent moisture so the soil doesn't get too dry and cause the plant growth to soil.

    Another somewhat common cause of bolting is over-fertilization.

    I think it is safe for us to assume that the erratic weather swinging from cool to hot back to cool back to hot back to cool to insanely hot is the reason y'all are seeing bolting, especially if you haven't been giving them one inch or more of moisture a week. This is, by far, the most erratic spring weather I can remember in terms of very extreme temperature swings.

    Y'all are making me nervous. I haven't had a single onion bolt yet but with the luck y'all are having, I'll be expecting it to start happening any day now. I have been really careful about watering, weeding and feeding them this year because I planted so very many and really wanted a nice, big crop because last year's was only so-so.

    The weather is against us this year, folks. After my poor little baby peaches and plums survived three different cold mornings with temps in the upper 20s and frost on two of those three mornings, I was thrilled that they were still hanging in there, growing and getting bigger. Then, the wind gusts we had the other day, which went as high as 54 mph, blew the fruit right off the trees. It was not totally unexpected as I've had sustained winds in the upper 40s do the same thing before, but it still is very frustrating. No matter what we do, it seems like the weather is against us.

    Now, I'm going to go find Bruce Frazier's bolting newsletter from last spring and link it below.

    Dawn

    Here is a link that might be useful: Dixondale's April 2010 Newsletter

  • slowpoke_gardener
    13 years ago
    last modified: 9 years ago

    I bought 2 bundles of Dixondale from M&M nursery, a forum member gave me some bulbs and I started some from seed, and other than some storm damage all are beautiful. This has been the year I just run by the garden and throw something at it and keep on going.

    I think I may just plant and go on vacation and come back about harvest time. The plants seem to be doing better on their own than when I work my butt off in the garden.

    Larry

    P.S. I think the no-till section may do better than I expected.

  • soonergrandmom
    13 years ago
    last modified: 9 years ago

    So far I haven't had a problem. In fact, I just went out in the dark and looked at them to see if any of them looked like they would bolt. I haven't watered or fertilized since they were planted, but my ground has never gotten totally dry either. I hope they don't bolt because I have other onion to use as green onions in addition to these 400 or so.

  • joellenh
    13 years ago
    last modified: 9 years ago

    That makes sense re size. I got several small Dixondale onions from Dody that she got during the group-buy thing you all had, and they are fine. Small, but fine.

    The much larger Dixondales that I got from Farmer's Feed in Sapulpa are mostly all bolting. Huge, and bolting.

    I've read conflicting advice re cutting the flower head off. This is my first year growing onions, so I don't know what source to listen to...

    Jo

  • biradarcm
    13 years ago
    last modified: 9 years ago

    So far none of our Dixandale onions are bolting. I check them this morning, all are doing fine, indeed I see some already started bulbing! I was late to work, did not take any pics, but will post some in my picasa this evening.

    The only onions which are bolting those I left purposefully from last year's planting. Now they become so big-cluster with huge flower heads, looks awesome. -Chandra

  • Okiedawn OK Zone 7
    13 years ago
    last modified: 9 years ago

    Jo, You can do what you want but the results are about the same either way in that you likely won't get a big full-sized onion that will store well.

    Some people prefer to go ahead and harvest bolting onions and use them as green onions as soon as they notice they are bolting.

    Other folks prefer to cut off the flower stalk, leave the foliage alone, and allow the onion to continue growing and to size up. Most bolting onions will go ahead and size up somewhat, although in my garden they usually stay a lot smaller than onions that didn't bolt. In a year when moisture is falling, the bolted ones are split and often water gets inside and causes some rot. In a dry year like this, that likely won't be an issue.

    If you leave the bolting ones in the garden, be sure you harvest them separately and use them up first because they won't store for long at all.

    Dawn

  • biradarcm
    13 years ago
    last modified: 9 years ago

    Here are some pics of onions;



    -Chandra

    Here is a link that might be useful: more pics

  • slowpoke_gardener
    13 years ago
    last modified: 9 years ago

    Chandra, everything is so beautiful, and so much ahead of my plants. How do you protect them from the wind?

    Larry

  • boomer_sooner
    13 years ago
    last modified: 9 years ago

    My Onions just sit their, maybe growing an inch taller each week, but not bulbing.

  • Okiedawn OK Zone 7
    13 years ago
    last modified: 9 years ago

    Boomer,

    I wouldn't be worried about onions that are not bulbing up yet because the earliest types are just beginning to bulb up.

    Onions bulb up in response to daylength. See the link below for a description of each type at the bottom of the page. Both short-day and intermediate-daylength types can be grown in most of Oklahoma, and people in far, far, far northern OK or southern KS can have some success with long daylength types.

    Short-day types that were planted in mid-Feb thru late Feb. usually are full-sized and ready to pick in May or early June depending on each variety's DTM, so could be starting to bulb up now. In a year that has had a warm spring, they're often a little bit bigger earlier than in a cooler year as long as they are well-watered. Most intermediate-daylength types take 3 or 4 weeks longer to mature and may not be bulbing up yet.

    I haven't looked closely enough at my onions to even notice if they are bulbing up yet, but I planted both short-day and intermediate-day types so probably some of them are. I've been too busy with fires and fighting the heat in the 90s and winds in the 40s-50s (and cleaning up downed limbs and leaves and fruit) to spend much actual time in the garden lately. I did spend 15 heavenly minutes in the garden yesterday, but in a garden the size of mine, 15 minutes barely gives you time to walk through and pull a few weeds.

    I did notice yesterday that many of my onions have 9 to 11 leaves which is a lot for this early in the year, so should have good-sized onions whenever they do begin to bulb up. With onions, you essentially get one 'layer' or 'ring' of onion flesh for each leaf, so the more leaves and the larger they are, the larger your onions will be. To get big onions, just keep yours well watered and fed well (though not overfed) with nitrogen, and when they bulb up, they'll be huge.

    Dawn

    Here is a link that might be useful: Daylength of Onions

  • boomer_sooner
    13 years ago
    last modified: 9 years ago

    Thanks Dawn.

    I'm growing two varieties this year. White Granex and 1015 texas sweet.

    How deep do you plant onion plants not seeds?

  • Okiedawn OK Zone 7
    13 years ago
    last modified: 9 years ago

    Boomer,

    You're welcome.

    I plant onion plants about 1/2" to maybe 3/4" deep. They are planted just barely deep enough to keep them upright when the wind blows hard. After last week's 54-mph wind gusts, they were leaning over a bit (OK, they were leavning over a lot) but have straightened themselves back up with only minimal assistance from me.

    Onions like to be planted shallowly. Those that are planted more deeply seem to grow more slowly and not bulb up as well. I don't know why. I've also noticed that onions which are planted more deeply are more prone to disease, especially in very wet spells. As the shallowly-planted onions start bulbing up, they'll seem like they are pushing themselves up above the surface of the ground a little bit. That's OK. In fact, it is a good thing. For some other odd and not-really-understood (by me) reason, they grow better when they are pushing up out of the ground and you should resist any urge you might have to cover them up with mulch or soil.

    Onions grow really well if we leave them alone and let them grow the way they want to grow.

    Dawn

  • biradarcm
    13 years ago
    last modified: 9 years ago

    Larry, I not protected them from wind. I guess property fence and raised beds might have provided some projection. -Chandra

  • seedmama
    12 years ago
    last modified: 9 years ago

    Chandra,

    I feel so tiny amongst your onions. What did you mulch them with, and where did you get it?

    Thanks,

    Seedmama

  • biradarcm
    12 years ago
    last modified: 9 years ago

    Seedmama,

    I mulched them with grass clippings from my lawn and some spoiled and chapped haybale which we bought for Halloween decoration. Other than I not added anything. Onions were the first crop to go with with new beds, I guess they had enough nutrients. So we had great harvest. I hope same thing goes this year as well.


    By the way, winter storm and snow predicted for the weekend, there will be couple of cold ways... If I plant onions this weekend (Saturday), does cold going to hurt them, will that lead to bolting? Or should I hold back onion planting?

    Thanks -Chandra

  • Okiedawn OK Zone 7
    12 years ago
    last modified: 9 years ago

    Chandra, I don't know that it is strictly necessary to wait and plant the onions after the cold spell, but it is hard to know for sure. I'd probably wait and plant them next week after the cold, snowy weather passes.

    However, if you choose to go ahead and plant them, just be sure there's enough mulch around them to protect them from the cold temps, or cover them up at night or on very cold days with a floating row cover, a sheet or a blanket.

    It would take a prolonged period of temperatures below 45 degrees to induce bolting, and I don't know if your temps will stay in that danger zone long enough to cause bolting.

    Also, check your onions' size when you get them. If they are smaller than the diameter of a pencil, or have less than 5 leaves, they shouldn't be large enough to bolt due to cold temps.

    Dawn

  • biradarcm
    12 years ago
    last modified: 9 years ago

    Thank you Dawn. If waether permits, I go ahead and plant them. and probably reserve half of the same variety for later planting to just to check weather magic. -Chandra

  • seedmama
    12 years ago
    last modified: 9 years ago

    Generally speaking, the onions are small with less than 5 leaves, and look very very good. In my mind only one variety is marginal in size. We had very few of that kind ordered and I'm not going to name it for fear if jinxing it.

    More later.

  • seedmama
    12 years ago
    last modified: 9 years ago

    Generally speaking, the onions are small with less than 5 leaves, and look very very good. In my mind only one variety is marginal in size. We had very few of that kind ordered and I'm not going to name it for fear if jinxing it.

    More later.