I've been given a courgette plant and a cucumber one, too.
Not really using the cold frame this year, I decided that they can go in there. The roots will be in a bit of shade, easily watered and adjacent to the soil in the outside world, but the foliage will be
largely, 'under glass', but with access for friendly bees, etc. Robins and sparrows have been spotted popping in there for invertebrate control, too.
They're also adjacent to the 'new' overflow barrel, so watering can happen efficiently.
We'll see if they like it in there...