Is it safe?

[bend1pa]

To leave my tomaoes outside 24/7 now? They are growing away well. But at night the air temperature is dropping to 5° C at times ( eg 7° C forecast tonight)

[Jungle Jane]

I’ve been leaving some of mine in the blowaway overnight with an extra sheet of bubble wrap insulation,temp has been 8 degrees,i have been bringing the others indoors that don’t fit in the shelter,it does look cold tonight. How big are your plants?

[ameno]

It's safe in so far as they won't die, but temperatures that low, especially if it's for several nights in a row, may well set them back, and cause their growth to stall for a week or more.
Personally I would wait at least a few more days, but if your plants are too big already and desperately need planting out then they'll probably be okay put out now.

[Vince G]

If I plant toms outdoors (generally because I've got too many for the polytunnel) I plant them in a place where the first rays of the rising sun hit them and start to warm them up. This is about 5am in tropical Suffolk at this time of year, so they're not subjected to cold for too many hours overnight

[bend1pa]

Thanks for your responses.

I’ve been leaving some of mine in the blowaway overnight with an extra sheet of bubble wrap insulation,temp has been 8 degrees,i have been bringing the others indoors that don’t fit in the shelter,it does look cold tonight. How big are your plants?

They are already the size where the 1st flower truss buds will open in a few days and the 2nd truss is visible. I have read in a few places that Toms should be hardened off, so I thought perhaps leaving them overnight at 7 - 10° C, would do the trick, and so far they seem to be okay. But lower temperatures are forecast, 6 - 7° C for the next few nights, but a bit warmer after then.

[peanut]

I'm only leaving mine in the unheated greenhouse wrapped in 2 layers of 35gsm fleece at 8c, any lower and I bring them all in. I'm desperate to get them planted but I won't risk it until we have a steady 10c overnight, which at the moment seems a long way off. I'm still getting nights of 4c forecast!

[Vince G]

To leave my tomaoes outside 24/7 now? They are growing away well. But at night the air temperature is dropping to 5° C at times ( eg 7° C forecast tonight)

Profile doesn't say where you are. If you're south of a line from the Bristol Channel to the Wash, you're fine. Sun is up at 430am so it's not cold enough for long enough to do any lasting damage