onions from seed

[bridget mc laughlin]

i have about ten seed trays of seedling onions and i would love to know if they would be able to put up with the cooler temperatures in my cool glasshouse or would i be better to keep them inside for a while longer

[Creemteez]

Hi Bridget,
Depends on how cool your glass house gets. Being up in NI I would imagine you are still likely to have some cold nights, but they should be fine in there during the day. If your glass house is at home then that would be what I'd do. Put 'em in there during the day and bring 'em in at night.

[zazen999]

Mine have germinated in a cold greenhouse - and a few that I popped into the heated prop to get going all go straight back outside once germinated.

All you are trying to do is to not let them frost over; and plant out once your last frost date has gone. If you molly coddle them they will flop as soon as you put them outside.

[LewaK]

My single tray of onions are in a utility room/lean-to that is essentially like a big ol' greenhouse, save that it's attached to the house with a fridge in it. They've germinated and are growing nicely, and as nights are hitting 6 or 7C around here (despite a predicted freeze next week) I'm tempted to put mine in a glass seedling house we have outside. Won't put them in the ground until it's warmer though - I don't want to lose them now!

[Two_Sheds]

As Zaz said, onions need to be on the cool side - if they are too warm they will suffer. They shouldn't be in the house

[binley100]

Mine are in the blowaway which is nicely sheltered by the back door......open by day and closed by night.........

[Aberdeenplotter]

As Zaz said, onions need to be on the cool side - if they are too warm they will suffer. They shouldn't be in the house

It is a misconception that onions need to be cool. The best onions grow in arid conditions such as in Spain and you will all have seen super spanish onions in the supermarkets. The important thing is to try to maintain a constant growing environment and avoid extremes of temperature be it hot or cold.

My onions are presently being grown at around 55 Farenheit and they will move to my polytunnel in April. The temperature in there can peak at over 80 even with the vents and dooors full open and it certainly doesn't appear to have affected these guys adversely

[Kristen]

I grow Onions with some heat whilst they germinate, but once pricked out I put them in my unheated greenhouse.

[zazen999]

It is a misconception that onions need to be cool. The best onions grow in arid conditions such as in Spain and you will all have seen super spanish onions in the supermarkets. The important thing is to try to maintain a constant growing environment and avoid extremes of temperature be it hot or cold.

My onions are presently being grown at around 55 Farenheit and they will move to my polytunnel in April. The temperature in there can peak at over 80 even with the vents and dooors full open and it certainly doesn't appear to have affected these guys adversely

Yes, if you have a polytunnel that's great. But growing them in the heat and putting them out in the cold once they have got used to the heat - tends to make them flop over.

[Pompeylottie]

Now I'm worried, I put my onion seedlings in the ground today! Luckily only a few that I sowed early.
Have to keep my fingers crossed

[Aberdeenplotter]

Yes, if you have a polytunnel that's great. But growing them in the heat and putting them out in the cold once they have got used to the heat - tends to make them flop over.

As with all plants grown under cover, if moving them to colder conditions, they need to be hardened off gradually first of all and that way they will not flop

[Shadylane]

Now I'm worried, I put my onion seedlings in the ground today! Luckily only a few that I sowed early.
Have to keep my fingers crossed

I have some red barons that have been out all winter Twas an experiment really, as I wanted to grow overwintering red onions from seed and couldn't find any. As suggested by onion guru Zazen I used regular ones and cloched them - well not all of them - and so far they've survived the heavy snow and sub zero temps. Will be interesting to see how they do. My other ones are in a placcie greenhouse. Sowed inside then put outside once through.

[Two_Sheds]

onions need to be on the cool side - if they are too warm they will suffer. They shouldn't be in the house

It is a misconception that onions need to be cool. The best onions grow in arid conditions such as in Spain

AP your onions are terrific.
Most people here don't have the brilliant light of Spain, and British houses (and most greenhouses in winter) are too dark for the poor little onion seedlings - they may be warm enough, but will grow straggly in poor light

[Aberdeenplotter]

TS, ta for compliment to my onions. It's very exciting growing the big ones as they visiblly increase in size daily. The ones in the photo were around the 4lb mark but the world record onion is 16lb 8.5ozs. I dream on.

[Two_Sheds]

.. size isn't important, it's what you do with it. How do they taste?