Dogwoods are known as under-canopy trees. However, heavy shade from trees may promote powdery mildew or leaf spot to form on the dogwood's leaves. By planting dogwoods in a sunnier, more open space, you get more flowers and less disease problems. Light shade in the afternoon is beneficial.
Dogwoods are shallow rooted and should be heavily mulched. They also need consistent soil moisture, especially for the first three years. During those years, place a soaker hose around the tree and leave the hose on all night, several times a week for sandy soils. For mature trees, thoroughly water every week during the drought season. Before watering, check the soil moisture several inches deep with your fingers, and water more or less frequently as needed.
Dogwoods are thin-barked trees, and any accidental hitting by trimmers or lawn mowers can be fatal to the tree. Many trees die from these kinds of accidents.
Cynthia J. Johnson, Smith County Master Gardener
Texas Cooperative Extension
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