Use Trays to Grow Sturdy Seedlings

You can. I do use some plastic plug flats, pots, and trays of cell packs, but I also like to use homemade wooden trays, because I can grow big, sturdy plants in them, and then reuse the flats year after year.

Choose a standard size for your flats, to make life simpler when fitting them into your warm, sunny growing space, as well as when calculating how much to plant. I have a large garden, and I use flats that are 12 by 24 inches. I make two depths: 3-inch flats for sowing seeds, and 4-inch flats for growing the seedlings. I don’t recommend flats bigger than that, because filled flats are heavy.

I gather small scrap boards and make up a batch of flats at a time. I usually end up making a couple of half-sized 12-by-12-inch flats to use up the wood scraps. I like Eastern red cedar or pine. Avoid oak. Not only is it heavy, but it also splinters painfully, and it’s not as easy to work with as soft woods. Avoid plywood and other manufactured boards, as the glues and fillers can be toxic to plants. Likewise, avoid pressure-treated wood.

I cut 12-inch-wide end boards of the thickest pieces, about ½ to ¾ inch thick and 3 to 4 inches wide. Because