Question
There are several different types of fertilizer on the market for trees and shrubs, including granular, pellets, stakes and liquid (for instance the deep root feeding by many lawn & tree companies). Can you tell me which type is the most effective? Thanks so much. Sincerely, Pam Hewetson

Answer
Most mature trees and shrubs need no additional fertilizer. especially trees which grow in or near lawns usually receive all the fertilizer they need from the lawn fertilization.

You can fertilize shrubs annually. I recommend granullar slow release fertilizers pellets and broadcast them evenly under the dripline (canopy) of the shrub or tree.

Fertilizer stakes/spikes are alternatives near large trees especially if you do not want to fertilize the lawn area or flower bed area in which the tree grow. In this case you drill down into the ground (6" or more) and drop the spikes in. this is a similar manner the tree companies does by "deep root feeding". This is not for the benefit of the tree... it is to avoid fertilizing the surrounding areas.

Trees have most of their feeder roots in the top layers of soil and fertilizers traverse (migrate) in the soil so they will eventually find each other.

As mentioned above, I recommend the granullar fertilizer pellets.

If you want to fertilize trees or shrubs do so once per year in spring.

Some shrubs benefit from fertilizers which are specifically formlulated to lower the pH soil value (e.g. acidify). A good  brand is HOLLYTONE. You can also buy miracid. These shrubs includes rhododendron, azaleas, and holly.