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PunkRotten
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Does a cold period trick plants into thinkng they are older?

Hi,


I planted some Parsley around August last year. And now it is late FEB and I think the Parsley is going to go to seed soon. I can tell by the stem and leaf structure. The lives are changing shape in the middle and the stem is growing thick in the middle and growing upwards.

And since Parsley is a biennial did the winter make it think it was already a year old? How long does it take green onions/scallions to put up a seed pod? I noticed today one of my green onions is getting a stalk with a little bud at the end. I planted these last year maybe in NOV.

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applestar
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As far as the plants are concerned, cold days and shorter days mark the end of a growing season, and lengthening days and warmth signals the 2nd growing season, so they are in their biennial/2nd year and it's time to flower and produce seeds.

Bunching onions are perennials like chives -- do they strt flowering 2nd year or do they flower their first year? Onion sets larger than dimes often grow flower stalks at the cost of bulbs and/or which makes them poor keepers. So gardeners are often advised to pull them and eat them as green onions and let the smaller sets mature into full size bulbs.

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PunkRotten
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That is interesting. I guess you could use this trick to your advantage by planting late in one year and get seeds the next if that is what you wanna do.

These onions I got are non-bulbing type. I am not sure whether I wanna let it flower or cut it off. Will the onion die after producing the buds?

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hendi_alex
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If I plant arugula, parsley, or cilantro during very cool or cold weather, they begin to seed with onset of the first warm weather. All three of those which were overwintered this year are either blooming or showing signs of developing flower stalks. I use a succession of plantings, with the last being planted near summer's end. Those always overwinter and are very productive when the winters are mild, with no hard freezes into the low 20's.

So yes, cold followed by warm weather does tend to trigger flowering in some plants. All three of the above are biennial plants so perhaps this is mostly a problem with biennials, though I've found that annual lettuce plants also tend to go to seed more readily if they were planted very early during cold weather. Just thinking of it from a biennials point of view, it is usually a warm growth followed by cold followed again by warm then seeding. So the trigger must be the cold followed by warm.

This is one reason that I rarely buy parsley or cilantro from a nursery for transplant. Those plants will often go to seed very early in the season. The outcome is totally dependent upon the growing conditions when the seeds were started and young plants developed.
Eclectic gardening style, drawing from 45 years of interest and experience. Mostly plant in raised beds and containers primarily using intensive gardening techniques.
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jal_ut
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Bunching onions are perennials like chives -- do they strt flowering 2nd year or do they flower their first year?
I can only say what my experience has been here with bunching onions. I plant them in April, and they can grow all season and never have flowered in my garden. I suspect they need a warm growing period then a cool period, maybe even with shorter days then warmer again and longer days to trigger the blooming.

I have only grown bunching onions as annuals. I like to grow them just for scallions.
Gardening at 5000 feet elevation, zone 4/5 Northern Utah, Frost free from May 25 to September 8 +/-

GardenGnome
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Hmm I have some bunching onion seeds so I should wait tell april to plant them?
Gilson (Giles) Zone 7b

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