What is a soil block and why do we use it?

A soil block is a block of growing medium that has been lightly compressed and shaped by a form. A soil block serves as both a container and the soil for starting and growing seedlings, eliminating the need for plastic pots and trays for transplanted seedlings. Seedlings grown in soil blocks form stronger root systems than those grown in containers due to increased oxygen to the roots and the soil block's natural tendency to "prune" roots. This creates a substantial advantage when seedlings are transplanted into the garden, because plants establish themselves more quickly and, because of lessened root disruption, they are less prone to transplant shock.

A typical 2" soil block contains as much growing medium as found in a 4" pot and 4" soil block contains as much growing medium as found in a 6" pot.