We’ve received a few questions recently about expected pH levels when using GreenTree Premium Soils™. Our suggestions are outlined here. If you have further concerns, please reach out to our retail team at (607) 272-3666. Any member of our team can answer specific questions you may have!

Our premium soil blends are buffered with lime in order to have a stable pH over time. Due to the alkaline nature of both the lime and azomite in our soil, the pH of outputs may be higher than the pH of inputs. Early pH readings may be high because a small portion of the lime is flushing through and adjusting readings. When growing in our biologically activated soil, as compared to hydroponics, plants are working symbiotically with microorganisms to acquire nutrients over time. Because of this, some organic liquid nutrients advise against adjusting pH in the solution, as levels will balance out in the soil. Some growers like to add humic and/or fulvic acid concentrate to condition their water before adding inoculants and nutrients. This improves nutrient availability and combats high pH readings early in the grow cycle. Another option is using pH Down from General Hydroponics or lemon juice to lower the pH of the water.

It’s important to remember that different crops prefer different pH levels in their soil. For annuals with a heavy fruit set, like tomatoes, a good rule of thumb is a pH between 6.0 and 6.8. Our Ultimate Blend is designed for these kinds of crops to flower, fruit and ripen in.