Compost tea is all the rage but does it really work? Research studies so far have produced mixed results. A 2007 meta data review on compost tea by Dr. Linda Chalker-Scott concluded that “Clearly, the science is not strong for aerated tea use on crop plants, much less on lawns, shrubs, and trees”.
There seems to be a lot of work done in this area but much of it is not published in peer reviewed journals and most of it has been done in labs and greenhouses, not in the field. Until the work is repeated in the field we can’t conclude it works in gardens.
The other problem is that controls have been poorly selected. For example, in one study (ref 3) they compared ACT compost tea to water, using lettuce that had been under-fertilized. Guess what, compost tea improved growth. This only proves that adding nutrients, when they are deficient, will improve growth. The study never compared compost tea to adding nutrients in other ways.
In this post I will review one study that compared the use of compost to compost tea.