I am experimenting with soil blocks in plastic totes. The best for me are the lower profile, clear totes with clear lids. If it gets cold, I can put the lids on secure and the temperature inside is 10-20 degrees Fahrenheit higher than the outside temperature. When it rains, I can remove the lids so they can enjoy the nutrients from the rain. So far, it seems seeds are germinating quicker and getting good germination rates.