Q.Boxwoods Are Evergreen So Can You Use The Same Fertilizer That Is Used On Rhododendrons And Azaleas?
We have cold winters in Central Oregon and very warm summers sometimes. When would I fertilize my boxwoods? I have read that late fall is the best time. Should I also fertilize them in the spring?
Certified GKH Gardening Expert
Boxwoods don't need fertilizer unless there is a nutrient deficiency indicated in a soil test. Their shallow roots can be harmed by excessive fertilization. They should be mulched, and the decomposing mulch will supply some nutrients and so will the lawn fertilizer if the shrubs are nearby.
The soil pH should be between 6.5 and 7.2 for boxwoods so they are slightly acidic. Rhododendrons and azaleas pH is very acidic, below 5.5, so I wouldn't use the same fertilizer. If you do need to fertilize, early spring, between February and early April, is the best time. They can be fertilized in late fall, but that could set them up for winter injury.