Peat Pellets (individual)
Jiffy pellets are purchased as small disks as shown above. When water is added, the dry peat moss or coco husk (coir) expands dramatically. In order to keep this material from falling apart, everything is contained in a fine mesh which forms the pot around the potting material.
Seed is inserted in the top and pressed into the potting mix. As it grows, roots will reach the fine mesh. Some roots find the mesh to be a barrier and stay inside the mesh. Other roots will manage to sneak out through the holes, but since there is no potting media or water outside of the mesh they don’t grow very far. In effect they are root pruned.
When the seedlings are ready to be planted you simply pop the whole thing into a small hole and water it.