This is my first season of growing vegetables and it appears i am a better farmer than i thought i would be! I only have a small patch and an average sized greenhouse and i think i may have planted to much. I now have hundreds of seedlings growing of all sorts of varieties and species. I imagine in a few weeks when they get bigger i will have to thin them out and discard some of the seedlings which i don't really want to do but i don't think i'll have any alternative apart from giving some to neighbours. What i wish to know if anyone could help me is minimum spacing for individual plants for Brocolli, Cabbage, Spinach, Onion, Carrot, Courgette, Sweetcorn, Parsnip and Tomatoes (money-makers)!!! Also, when i should start thinning out, at the moment they are all to small and delicate to move. How many weeks after they seedlings first appear are they strong enough to survive being moved about?