[Mark's Sussex Allotment]

Evening guys.

I've sown some tomatoes, peppers, and cucumbers in the polytunnel, in a propagator under a sheet of fleece.

I'm in littlehampton, and it's going to be 8 degrees for the next week.

All packets say February sowing is ok, indoors, and I know indoors means heated greenhouse or actual house, but do you think they'll germinate and be ok?

Germination time is 10-21 days across the varieties and the polytunnel was 34 degrees today.

By the time they are big enough to prick out it'll be middle of march....

[sunshineband]

All of these need actual warmth to germinate ie 20degC so you may find nothing comes up at all I'm sorry to say, wizzyfax 

[Nikkithefoot]

Its not the daytime temps you need to worry about so much as certainly it will be a lot warmer than 8'C inside the tunnel. Its the night time temps. If you can provide bottom heat over night then you might get away with it. Otherwise bring indoors overnight. Ideally need a fairly constant temp of between 10-15'C to germinate successfully. Lower temps may cause slower germination or even failure to germinate.

I personally have tried Jan / Feb sowings with bottom heat, then its a struggle to keep them growing on properly, again need temps above 10'C, plus overnight protection from later frosts. Sowing in March does mean they are a bit behind but they should catch up, and you are less likely to lose them.

[Headgardener22]

I agree with Nikkithefoot, I've found its best to bring stuff in overnight.

However, a couple of years ago I germinated everything out in the polytunnel (I sowed way too much) but:

1. I'd bubblewrapped the Polytunnel;
2. I built a covered area within the polytunnel; and
3. I put a greenhouse heater in overnight to try and keep the temperatures up.

It worked but was a lot more concern than sowing fewer and bringing them in overnight

[beesrus]

Brassicas may germinate in those conditions this time of year, but you might be pushing it a bit to get peppers to do so.

[DD.]

It's not just the germination issue either.

The plants are going to need a minimum temperature of around 10^oC - including overnight. I've just sown a few peppers and tomatoes that are destined for a heated greenhouse - and only a few.

The sowing for the unheated greenhouse will not take place for at least another month and that will still be indoors. I won't consider putting this sort of plant into an unheated greenhouse until towards the end of April at the earliest and more probably in May.

I know that you will be a little ahead of us on the south coast, but not this much.

[DD.]

I'm in littlehampton, and it's going to be 8 degrees for the next week.

They BBC forecast only gives 3-4 degrees on Friday and Saturday night and for most of the week only about 5 or 6 degrees overnight. These are not germination temperatures. Insulation will only delay a drop in temperature, it won't heat up a structure on its own.

[JayG]

Cue timely reminder of a useful guide to germination temperatures: 

http://tomclothier.hort.net/page11.html

As DD has already pointed out, tender plants need a minimum of around 10C to avoid getting checked, and even if your temperatures don't drop below that, your seedlings won't take kindly to the variation between night temperatures and your 34C daytime temperatures.

[Mark's Sussex Allotment]

They are safely on the windowsill in the spare room.

[3759allen]

after an experiment last year i'm only starting bare minimal toms and cucs early, just one or two plants to get an early crop. haven't even started them yet (prob won't for at least a couple of weeks). too much hassle and space needed for the results, moving tall plants in and out every day, hardening them off, worrying about late frosts.

i found last year the toms and cucs i germinated in the tunnel with no heater and spent their whole life in the tunnel produced a lot healthier plants and greater crop. and best of all no hassle, i like an easy life if pos.

[Headgardener22]

Bought myself a mini greenhouse from Wilkos (£10). Going to put that up inside the polytunnel and start germinating some tomatoes this week (got to get some seed compost first).

[3759allen]

Bought myself a mini greenhouse from Wilkos (£10). Going to put that up inside the polytunnel and start germinating some tomatoes this week (got to get some seed compost first).

we've got over night lows of 2 degrees predicted this week. i wouldn't be confident of over night temperatures being high enough for a month or two yet. even if they do germinate the plants will take a massive knock from cold nights.

i'm not even ordering my seeds yet so i can't be tempted. lol

[Headgardener22]

In previous years, I've germinate loads of tomato seedlings (1000+) and done it in the polytunnel in a greenhouse within the bubblewrapped polytunnel with a a heater to keep the temperature up. This year my plan is to do far fewer (<100) which I'll move in and out day and night. The Wilko greenhouse I'll use to give me time to move them in later in day.

[3759allen]

you must be very enthusiastic or a little nuts to move 100 tomatoes plants in and out for weeks on end. lol

just thinking it may be worth making some sort of black cover for the bottom foot or so of the sides and floor so it will retain heat for a little longer.

[adri123]

We are all living in the wrong country.  Equator is the place to be if only...