Is it all right to use standard potting soil for the marijuana plant? It’s seems like too much of a hassle to purchase and measure out fertilizers.
Certain standard potting mixes will promote healthy marijuana plant growth for a month or two because they are nutrient enriched. Other mixes have little or no nutrient content and need to be used with fertilizer right at the beginning.
Nurseries that propagate bedding and annual plants seek fast growth. They use mixes based on peat moss and supply nutrients with water-soluble fertilizer in the irrigation water. I saw nurseries in Holland use this technique when growing marijuana. The things of primary importance with a mix should be its pH, texture, porosity, and water- and air-holding capacity. The mix needs to have a pH of around 5.8 to 6.5. To adjust this, use pH Up or Down in the water. The medium should not pack tightly when squeezed in a fist. If it does clump, it should dissolve when poked. The material needs to have particles that are large enough to accommodate spaces for air so that the roots can get oxygen. Excess water needs to be permitted to pass through, but the medium still needs to hold enough to consistently moisten the roots.
Robert