I save & use containers like this to start seeds in. They are deep enough, they have drain holes in the bottom and vent holes in the top, the top snaps shut, and when the seedlings get large enough, you can leave the top open so they can grow higher. I use a single layer of a piece of paper towel in the bottom to keep the soil from going out the drain holes. By the time it's time to transplant the seedlings, the paper towel has broken down into almost nothing. AND you can write the name & date right on the top with a magic marker!