This week I started several peat pots of lettuce, spinach, broccoli, tomato, parsley, and sweet peppers in my window sill seed starting box(black plastic tray with clear top). I have a cold frame set up in my garden. When do I transfer my seedlings from the window sill to the cold frame. My thought is place them in the cold frame as soon as they germinate to get them used to their outdoor environment as soon as possible.