Kitchen Garden Forum

Do I still need to harden of plants I've grown in the greenhouse at this time of year? I'm looking to plant out courgettes and sweetcorn. If so, how long for?

I would think it depends on the difference in temperatures in your greenhouse and outside, I see you put where you live but I have no idea where Fermanagh is. If the difference in temperature is very small you can probably safely put them out now. If the difference is greater, then harden them off for a day or two more

I would certainly try to take a little more time over hardening off because greenhouse temperatures this time of the year will be considerably higher during the night because of the stored heat from daytime sun/brightness. I would suggest keeping things out during the day for 4 or 5 days but taking them in at night, then keeping them out over night PROVIDING it's reasonably mild. Only then plant or keep them outside for good. I would certainly take at last a week over the hardening off!

I really do not think that there is a need to harden off plants this late into the year.I would plant out direct and expect there not to be any check in growth.
My plants are raised in a tunnel that is open at both ends so my plants are grown by the hard method. For seeding early on in the year I have tunnels within the tunnel and heat available if necessary but it is seldom used.
JB.

Like Johnboy my greenhouse is open to some airflow day and night, after danger of frost is past again tough treatment but plants are quite hardy if we don't over cosset them. I planted out several lots of seedlings this past week without hardening off and they are all fine.