Two Tips to Beat the Ticking Clock
Onions. One of the great frustrations of gardening. You plant seeds and they turn out puny. You plant sets and they bolt to flower or rot or something. Not worth it, people say.
But really, it's not rocket science, or magic. It's just knowing two things:
So, Tip #1:
You always hear that rich soil, manure, nitrogen, etc isn't good for root crops like carrots or beets. Remember that onions aren't roots. The bulb is made from the bases of the leaves. The roots grow out of the base of the bulb. So, think of them as a leafy green and fertilize accordingly. I've seen even very experienced gardeners starve their onions (and potatoes, too) because of the word "root". Bulbs and tubers LOVE nitrogen.
and, Tip #2:
An onion grows and makes leaves until the day length reaches a certain number of hours. Then, it stops making leaves. The existing leaves start to swell up. The bottom of each leaf eventually swells so much it becomes a ring of the onion. Each onion variety has a specific number of daylight hours that will cue this process.
So, if you sow onion seed now, it has time to make a big plant before the days get long. It can make lots of leaves. Lots of leaves = lots of onion rings. If you start them later, they will be still small when the magic date arrives. And, if the soil gets really warm before they get those long days, they will forget bulbing entirely and make a flower instead.
Short-day varieties, start to bulb when they get 10-12 hours of sunlight. For intermediates it's 12-15, for long-day varieties it's 14-16 hours of light per day. The line between short and long day varieties runs from Washington DC to San Francisco, with intermediate areas being close to that line.
Grains like Wheat and Barley are day-length-sensitive too. The plants will grow bigger and make more leaves and stems while the days are short. As the days lengthen, the plants get ready to bloom and then to mature seeds (grain). Harvest is just after the longest days of the year.
Do you have to understand all this? No. Just understand that you need to start onions now. They can be indoors or in a greenhouse, but they need soil that is 60 degrees or so. They are little bitty things for the first couple of months, so if you sow a couple of pots with onion seed, about 1/2" apart in the pots, you can add them to your tomato and pepper starts without much trouble. Grains should be started directly in the garden--they love cold mud--as soon as the soil can be worked and planted.
This is the most common-sense explanation of growing onions & grains that I've read. I have long said a similar thing about garlic: treat it like a leafy green in the spring and feed it nitrogen, which will give the plant a robust start. Later, stop the fertilizer and let it focus on making bulbs. Each leaf is a wrapper around the bulb. Makes sense with grains, too. If we understand how the plants respond to the changing daylength and what they need to do to produce offspring before the frosts come, we can better understand how to maximize their potential. With your permission, I'd like to link to your article in my newsletter. Thank you!
3/16/2022 12:03:01 am
I love your explanation that onions are just swollen laves and therefore need to be fertilized like leafy vegs!
2/14/2023 07:44:30 pm
I agree with Blythe’s comment. This is an excellent general summary of how to grow onions and it is what I have been looking for. Thank you for taking the time to explain it all at a simple, fundamental level. It makes sense now.
Leave a Reply.
Jamie Chevalier lives and gardens on a river in the Coast Range of Northern California. She has gardened professionally in Alaska and California, as well as living in a remote cabin, commercial fishing, and working with seeds. She is the proprietor of Quail Seeds.