Japanese maple, known botanically as Acer palmatum, is a species of small trees with hundreds of known cultivars. Japanese maples are beloved for their colorful foliage that can range from green to deep purple to brilliant coral red. The leaves, bark and leaf stems can all hold unique colors and some foliage is patterned or variegated. The Japanese maple can reach 25 feet at maturity and the growth habit can vary from upright to spreading to weeping. Acer palmatum cultivars are not heavy feeders and light yearly applications of fertilizer are more than sufficient when the trees are grown in proper conditions.
Fertilize your Japanese maple cultivar twice each year, once in the spring after the last hard frost and again in midsummer.
Cast a complete, granular fertilizer such as a 10-10-10 evenly around the root area of the maple tree, applying one-half of the label recommended dose. Keep the fertilizer at least 6 inches away from the trunk to prevent over-concentration and burn and extend to past the drip line of the Japanese maple.
Nestle the fertilizer grains into the top inch or so of soil with your hand or a trowel or cultivating fork.
Water the fertilizer and surrounding soil in well until the soil is saturated to a depth of at least 6 inches. Maintain evenly and consistently moist soil at all times, never allowing the soil to dry out beyond the top 1/2 inch to inch of soil.