English Boxwood Decline: Management and Replacement

English Boxwood (Buxus sempervirens 'Suffruticosa') shows yellowing, dieback on half the plant after drought stress from broken sprinkler. Suspected "English Boxwood Decline" (complex of fungi: Paecilomyces, Volutella, Macrophoma).

Key Points

• Decline is irreversible; affected plants never recover fully.
• Fungi exploit stressed plants (drought, poor drainage, nematodes).
• No curative fungicide exists.

Action Plan

1. Remove diseased plant entirely (roots and all).
2. Do not replant boxwood in same spot for at least one full growing season.
3. Improve drainage and avoid overhead irrigation.
4. Plant resistant alternatives: 'Green Velvet', 'Green Mountain', 'Winter Gem' (B. microphylla hybrids) or Buxus sinica var. insularis 'Nana'.
5. Sanitize tools between plants.

Prevention for Remaining Boxwoods

• Water deeply during drought.
• Mulch 2–3 inches; keep away from stems.
• Annual compost top-dressing.
• Monitor for early symptoms.