Heat treated onion sets

[Binky]

Having struggled through the winter, my onions (Radar) are now bolting. Does anyone know of a source that sells heat treated sets for overwintering?

[Johnboy]

Hi Binky,
If you scroll down a few in Best Practices you will find other people in the same predicament.
JB.

[John]

Just a thought.
What does the heat treatment of sets consist of? Is it possible to do it at home - say in a low, low oven or even to nuke the sets in a microwave for a minute or so?

John

[Beryl]

Binky - I think as JB has said it has just been one of those years for Autumn Onions running to seed. Mine have done the same. If you take out the seed head you will still be able to use the onions but they won't store for long. Use them up first. Better luck next year.

Beryl.

[Nature's Babe]

I have the same problem with onions running to seed, and I am wondering about best plan for onions next autumn. I planted a few garlic under a mulch of straw and dried lawn clippings last year, and some
without mulch, this spring they grew up through the mulch and are the best garlic I have ever grown, so I plan to give my autumn sown onions and garlic the same protection this winter, and to see if it makes a difference as it has for the garlic. Hopfully it will afford some protection against the cold and also conserve moisture in the spring.

[Geoff]

I tried Autumn planted onion sets for the first time last year. They were Radar and less than 10% survived the Winter unprotected, the few that did look OK. I also sowed Senshyu Yellow in modules on 3rd August. I haven't noted when I planted them out but I kept a corrugated plastic cloche over them all Winter. I only lost a few and they are almost ready to use. What I don't know is which is more important, the variety or the protection. I think I shall probably go for Senshyu Yellow again, didn't buy any seed as I was waiting for the results when I did my order.
My maincrop Onions are always from seed sown in the heated greenhouse when I switch on in mid-February, 13th this year. Grown in clumps as per Geoff Hamilton blocking method from years ago but using the small pots that you can get 15 of in a seed tray.

[Johnboy]

I suspect that the very cold night temperatures that we have been experiencing this year are responsible for many onions heading up to flower. For an onion to flower it is normally in their second year of growth and having gone through an earlier warm period to experience a very cold period makes the plant act as though it has gone through a winter. Hence the flowers.
JB.

[glallotments]

Just a thought.
What does the heat treatment of sets consist of? Is it possible to do it at home - say in a low, low oven or even to nuke the sets in a microwave for a minute or so?

John

I'm not sure how they do it but I guess it's fairly complicated or you just end up with cooked onions!