One of my sunflower 'seedlings' is already 80cm tall...

[ErrolTheDragon]

And it's got the start of a flower forming, a good centimetre in diameter. It's in a 14 cm pot, in the kitchen by the patio doors. Another is nearly as big.

All the advice seems to be to wait until all chance of frost has passed before planting out but that could be the best part of a month. (I'm in Lancashire.) I've not got a greenhouse. I suppose I'd better pot on the 2 largest anyway, but do you think it would be possible to harden them off now or should I resign myself to indoor triffids for a while longer?

I planted a couple of our similar giants out last weekend and so far they’re still going strong. We are in the SE.

I planted one of mine out today and kept two indoors. Poor thing is the experimental one but if it copes with the cold nights it's siblings will be joining it this weekend. Meant to stay above freezing next week so fingers crossed.