Uh, you know these get 6+ feet tall don't you? They are not going to be happy inside your greenhouse...one of them could possibly fill it up. You could plant one or maybe two in a 5-gallon bucket or planter. Or, if you have ground area plant them in the ground...these are not made to remain in the greenhouse. I think of your greenhouse as a germination, seedling growing, new plant starting container...not to finish growing out a crop of tomatoes in.
Hmm, I just looked at a report on your climate....mid-60F degrees in the middle of summer??? That is in the low range of the growing temperature for tomatoes.
You definitely want to have them outside in a large container or transplanted into the ground by the first of June to have time for tomatoes to make. You could grow a couple or maybe three pepper plants in your greenhouse...they like hotter weather/temps. I'm sorry, but until just now I did not realize the summer temperatures that you have.
Do you have a patch of ground to plant in or will everything be grown on the patio in pots or buckets?
Are you close to the Cardiff area? That appears to be the warmest area.
