Question
In the Augusta, Maine area, what is the best fertilizer to use for apple trees?

Answer
Fertilize your apple trees two times a year May and July. Do not fertilize in late autumn as this will stimulate tender, late season growth which could be injured in winter.

When selecting a fertilizer, be sure it is a balanced type (8-8-8 or 10-10-10).

The general rule-of-thumb is to apply one pound of fertilizer per year of age of your tree up to a maximum of 5 pounds for a mature tree. Spread the fertilizer evenly under the canopy of the tree, out to the drip line.

If nutrition levels and soil pH are correct, then you should expect your young trees to produce 16-24" of new growth per year. If the rate of growth is significantly less than this, collect a soil sample and have your local county extension office analyse it. Based on their recommendation, you would then adjust your fertilizer and/or liming program.

Soil pH should be 6.0 - 6.5 but Maine soils may actually be below this and liming is therefore warrented. Before liming, however, make sure you have tested the soil pH as too much lime is worse than not enough lime.

Generally, if the tree is growing in a lawn which is fertilized with lawn fertilizer, avoid adding more nitrogen. The fertilizer should then be 0-10-10 or 5-10-10.