They do look a bit forlorn. I have only grown them in the greenhouse and waited until they fruited before I fed them. I expect they are quite healthy. Might they need potting on?

Hi Hank, they look as though they need water to me, it looks like a peat based compost too, they prefer loam based, plenty of water, high humidity, and a temperature between 70 and 75 f, Derek.

Thanks for the replies, they're in my conservatory and we've had some warm weather recently. And I'd no idea they preferred loam based compost.
It's a poor photo actually - doesn't show them at their best. But as with toms, I'll wait until the fruits appear before I feed them.