Q: I found some cotton seed meal to put around my blueberries. When and how much should I use? Should I use 10-10-10 on them too?
A: One of the great things about using organic fertilizers like cottonseed meal is that nutrients are released only when the soil warms up. If you put 10-10-10 on your plants now, the first rain will dissolve the chemicals and they will be wasted if the plant roots are cold. Organic fertilizers, on the other hand, depend on soil bacteria to decompose them and release nutrients.
There is a lag time between when roots are able to absorb nutrients and the time bacteria fully digest and release the nutrients from organic materials. You can get around that by putting a one-fourth inch layer of cottonseed meal under your blueberries in February and then scattering a one-half cup of 10-10-10 per 100 sq. ft. over the area in late March. In this way your plants will get “breakfast” in March and a”big dinner” in April-May.