I started my trays already thanks to my dear honey, who knowing my "quirks" as he calls it, bought me mobile cold frame. Normally you can build your cold frame outside and plant first early salads or herbs and let the sunshine warm it up through glass frames creating much warmer inside environment. Well mine is slightly different. It's a 4 shelf structure on wheels.
As you can see from picture above, he wired fluorescent lights on each level so my seeds won't get "weedy". It's also completely covered in plastic that can be un-zipped if it gets too warm inside but that's what allows warm air to stay inside and not escape into the room. So all I had to do was make a seedling mix - part organic peat moss and part soil, fill my seedling cups that are made out of recycled carton and is biodegradable, soaked it with water and planted my seeds. So far I have Broccoli of course, Swiss chard, 3 types of basil - regular sweet basil, purple and lemon type. Also some arugula, salad, some pink Brandywine tomatoes for early start - majority will be planted in about 3 weeks from now.Each shelf can fit 3 of such trays so closer to mid-march I will start on my tomatoes, peppers and other goodies. By then I hope to transplant my Broccoli and Swiss Chard outside and clear out more space for new batch. I will be rotating seedlings every month or so to get smaller amounts but keep it growing in waves. This way it won't overwhelm me with harvest all at once and I'll be able to pick more each week.