Fertilizer uptake is greatest when applications coincide with periods of high nitrogen demand from peach trees.
For early varieties (May to June): apply one-third to one-half in spring. In general, apply less fertilizer for early varieties than for later varieties because of the inherent vigor in the earlier varieties.
For mid- to late season varieties (July to September): apply one-half to two-thirds of the fertilizer nitrogen in spring, so it is available during the main flush of spring shoot growth.
Applying less than the full amount of nitrogen and making more than one application throughout the growing season increases uptake efficiency and minimizes leaching losses, especially in sandy soils where storage capacity is limited.
Multiple applications help maintain nitrogen in the root zone. Fertilizing during fall and winter is not recommended, because tree capacity for nitrogen uptake is low at these times.
Avoid over application of nitrogen fertilizer because the resulting succulent growth and dense canopies can lead to greater pest problems.