As a general rule, we recommend against fertilizing trees with chemical solutions. If applied incorrectly, chemical fertilizers can be harmful.
However, in some cases, particularly for older trees in distress, organic supplements such as mychorrhizae (at right) can be helpful. When we inspect your tree(s), we will recommend the use of mycorrhizae when we think it will add to a tree's vitality.
Use extreme caution when a tree service advises that you fertilize your tree(s). Fertilization is a very profitable business. Make sure you understand why they are making their recommendation, and ask them to explain about the product they will be using. If you think it would be helpful, get more than one opinion.