I picked the foam bottoms up from a Top's supermarket. The lid to a cardboard box works well if you can’t find the grape containers. I drilled three small holes down the center of the bottom of each container, laid a couple of sheets of newspaper on the bottom (to keep the dirt from falling out) and added about an inch of dirt on top of the newspaper. Fill each baggie with 3 -5 inches of dirt and water all the bags and let drain good in the kitchen sink. When dirt is still a bit moist, I add my seeds--pressing them down a tad. Insert a label in each baggie as you go and place in container. I made a list with the number and name of seed each baggie contains, to coincide with each label. A few seeds missed the baggie and grew in the dirt surrounding the pots. Close baggies, leaving small opening (about an inch) and put outside in container(s) anytime after December 15th. In the spring hold the the baggies open with a clothes pin so the plants don’t get over-heated. Make sense?
Now For The Labels
I cut my labels from venetian blinds and etch in numbers on metallic tape which I purchased from Home Depot. I have forgotten what the tape is called, but you peel and stick to blind.After last frost, transplant sprouts into garden
If you go the paper pot route, you need to make a rafter from a hanger or whatever and place the containers in a large plastic bag. You also need to cut holes in the top of each bag so the dirt stays moist and gets air. I crisscrossed my hangers and tightened them with pieces cut from an old pair of stockings. I LOVE my old stockings. I use them to tie plants, hold pieces together after gluing and on and on…