I don't need many of most plants, and I hate to buy the little 6 or 9 packs knowing I only need 2 or 3 plants. So what I did is save those 9 pack trays and start my own seeds. To keep track of what is where I decided to number each tray.
I used the side I numbered to orient a grid of 1 thru 9. Then I wrote down what I planted in each tray. For the most part I planted 3 of each type of plant, except the last tray where I planted ones and two's.
Before I planted the seeds I took some old pots with a vermiculite mix and mixed the soil with some peat moss in a bucket. Then I filled the trays full, wet the soil, and gently packed the soil down. Then just to make sure the soil was fully wet I let the trays sit in 1/2" of water for 15 minutes. When I brought them into the house the soil was moist, but not wet. I used a sharpened pencil to make holes for those seeds that needed to be buried.
I have had limited success in starting seeds before. My problem seems to be that I am planting too many types in one container, a zucchini will hit the top of the tray's plastic lid before some other seeds are up. The leaves of the zucchini then start to die because they are wet, or if you open the top the other seeds dry out and don't do well. So instead of placing the trays under a tray cover, I placed them in my green house. This is not a big expensive green house, just the opposite in fact. I had a raised bed that I screwed tomato stakes to, then I covered it with clear plastic. That simple.
Ok, maybe not. My cat keeps jumping on top of it and poking holes in the plastic, and I have to cut a hole in the side to access anything.
It does not look good, but the stuff it has grown for us this winter has been great.
The cabbage, garlic, strawberries, butter lettuce, and spinach have done the best. I also recently transfered some parsley, cilantro, onions, and carrots in there too. There is also rose mary, and some pineapple tops that I rooted. Not bad considering I spent less than $20 to build it.
I put the seed trays where I have harvested the lettuce and some of the cabbage. Hopefully, in a few weeks I will be transplanting lots of great stuff; Sage, Thyme, Lavender, Lemon Basil, Lemon Balm, Flat leaf Parsley, Rosemary (a different variety than what I already have), Bush Spicy Globe Basil, Genovese Basil (*H), Butter Lettuce, Sungold Select II Tomato (*H), Ground Cherry or strawberry husk tomato (*H), Purple Tomatillo (*H), Arkansas Traveler Tomato (*H), Money Maker Tomato (*H), Cherokee Purple tomato (*H), Cayenne Peppers long thin (*H), Serrano Tampequino peppers (*H), Red marconi peppers (*H), German green tomato (*H), Great white tomato (*H), Pineapple tomato (*H), and chives.
(*H) - The *H stands for an Heirloom variety.