Why Dogwood Trees Fail to Bloom and How to Fix It

Common Causes of Poor Flowering in Dogwoods

Three-year-old dogwoods in Connecticut that haven't flowered may be suffering from excessive nitrogen, often from lawn fertilizers containing weed killer (e.g., Scotts Turf Builder with herbicide). These products target broadleaf plants and can severely damage or kill dogwoods.

Immediate Remediation Steps

• Stop using weed-and-feed products anywhere near the tree's root zone.
• Apply a low-nitrogen fertilizer such as 12-4-8 or 16-4-8. For a 6-foot tree: ¼ cup (4 tbsp) in March and July, broadcast over a 2-foot radius.
• Water thoroughly after fertilizing.
• Mulch 3–4 inches deep with pine straw, bark, or leaves to conserve moisture and protect trunk.

Fertilization Guidelines by Tree Size

• Small trees (12–24″): 1 tbsp in March and July.
• Established trees: ½ lb (1 cup) per inch of trunk diameter (at 4 ft height) in March and July.
• Spread ⅓ of fertilizer beyond dripline where roots extend.

Key Takeaway

High-nitrogen lawn fertilizers with herbicides are a leading cause of dogwood decline and bloom failure. Switch to targeted, low-nitrogen tree fertilizer and maintain a wide mulch ring.