One advantage is that when you transplant, you can set the seedling a bit deeper in the next pot, which makes for a stronger root system. This is because tomatoes have those little hairs along the stem (look closely, you'll see them!) Those hairs will sprout into roots if they get buried under soil. This transplant method works especially well if you find that light levels weren't sufficient and your seedlings are a bit spindly. Happy gardening! > >>2. Seed manuals and yourself mention that after true leaves appear, it is > time to put them into bigger pots, such as 4" pots. Other than shelf > space, > is there any reason why seeds should be started in small containers and > then > transplanted to larger ones?