Dwarf Weeping Cherry Yellowing: Watering Correction and Shot Hole Check

Diagnosing Sudden Leaf Drop

A dwarf weeping cherry in hot, humid weather with daily sprinkler irrigation showing yellowing, curling, brittle leaves and leaf drop—especially on the west side—has two likely issues:

1. Overwatering / Poor Watering Practice

Daily light sprinkling keeps foliage wet (promoting disease) and encourages shallow roots. Switch to deep weekly watering: turn off sprinkler; apply 1 inch via hose at base once per week.

2. Shot Hole Fungus Check

Examine fallen/yellow leaves for small round holes penetrating the leaf—classic shot hole (Wilsonomyces carpophilus). If present, it's cosmetic; 20% defoliation max, not fatal.

Immediate Actions

• Stop daily sprinkler.
• Water deeply weekly at base.
• Mulch 3 inches (not on trunk).
• If shot hole: rake fallen leaves; copper fungicide next spring at bud break.

The "cool sprinkler water on hot leaves" thermal shock also contributes. Correct watering usually resolves the crisis.