Propagation Cubes and Mixes

Marijuana Horticulture

by Jorge Cervantes

Rockwool root cubes, peat pellets, and Oasis blocks are pre-formed containers that make rooting cuttings, starting seedlings, and transplanting them easy. Root cubes and peat pots also help encourage strong root systems. Peat pots are small, compressed peat moss containers with an outer wall of expandable plastic netting. The flat pellets pop up into a seedling pot when watered.

Place a seed or cutting in a moist peat pot or root cube. If the little container does not have a planting hole, make one with a chopstick, large nail, or something similar. Set the seed or clone stem in the hole. Crimp the top over the seed or around the stem so it makes constant contact with the medium. On one to three weeks, roots grow and show through the side of the cube. Cut the nylon mesh from peat pots before it gets entangled with roots. To transplant, set the peat pot or root cube in a pre-drilled hole in a rockwool block or into larger pot. Clones and seedlings suffer little or no transplant shock when transplanted properly.

Check moisture levels in peat pots and root cubes daily. Keep them evenly moist but not drenched. Root cubes and peat pots do not contain any nutrients. Seedlings do not require nutrients for the first week or two. Feed seedlings after the first week and clones as soon as they are rooted.

Coarse sharp sand, fine vermiculite, and perlite work well to root cuttings. Sand and perlite are fast draining, which helps prevent damping-off. Vermiculite holds water longer and makes cloning easier. A good mix is one third of each: sand, fine perlite, and fine vermiculite. Premixed seed starter mixes sold under such brand names as Sunshine Mix and Terra-Lite are the easiest and most economical mediums in which to root clones and start seedlings. Soilless mix also allows for complete control of critical nutrient and root stimulating hormone additives, which are essential to asexual propagation.