You can plant seeds directly into these pots or wait until they are germinated and maybe 1 1/2" tall, then transfer to these tall pots. The extra height in the pots allows the tap root to grow straight down and will enhance the tree growth. You also find you use less pot, less potting mix, less fertilizer and less water to get the tree ready to transplant to larger pots or the ground, that means big money savings.
You will need something to stand them up in. I use large tubs (shown in the pic below) that hold them upright for growing. I am also looking for some flats, they won't stand up by themselves. Sides are well sloped so depotting is a breeze.
Here's another idea for you. When your tree or shrub has been in the pot long enough for roots to come out the bottom looking for more dirt, you can cut a six inch diameter hole in the bottom of the pot, and then sit that pot on top of another pot about the same size that is full of mix almost to the top. Nest one pot in the other and you have a very nice double high "tree pot".
It will give you a lot more growing time in the same diameter pot, and your tree will be healthier, This will work withon small pots or large pots, makes no difference.
Part# - STUTPOT9B - 3.75" X 9.5"
50¢ each + shipping.
Part# - STUTPOT1B - 4.0" X 14.0"
No longer available.