Flowering dogwood trees and shrubs have a reputation for being somewhat delicate and persnickety about their growing conditions. This is largely because they are naturally a forest dwelling, understory tree that is rarely disturbed. Modern landscape settings are rarely tranquil nor protected, hence the trees sometimes struggle to establish themselves, according to the University of Kentucky. Perfecting the basic cultural requirements will allow most dogwoods, of flowering age, to produce a repeat annual bloom.
Check the soil moisture content by feeling it at the surface and at a foot down. Dogwoods must have moist, but not consistently sopping wet soil. Their roots are shallow; therefore, the trees experience drought stress sooner than most others. Water dry soil until drenched, at 6 inches down. Water away from the trunk and out past the drip line of the tree. Never allow the soil to become dry beyond the very superficial crust.
Mulch around the base of your dogwood, twice a year, with several inches of organic material such as compost, shredded bark or leaf mold. Mulch will help keep the root zone moist, cool and protected from disruption by foot traffic. It will also keep competitive weeds at bay, which removes competition for water and nutrients.
Fertilize your dogwood twice a year in the spring and mid-summer with a slow-release or organic fertilizer formulation designed for acid-loving plants. Look for a product for holly, azalea and rhododendrons with a guaranteed analysis of 4-5-4 or 5-1-1. Don't use quick-release chemical formulations, as these can burn the roots and stress the tree. Apply according to the label dosing directions to the surface of the soil and water in well until the soil is drenched a few inches down.