Diagnosing Brown Leaf Edges on Rugosa Rose

Rugosa rose shows brown leaf margins on lime-green foliage. Owner seeks cause.

Primary Suspect: Water Stress

Brown leaf edges = classic drought symptom. Even daily watering may not suffice in heat. Potted plants especially vulnerable.

Secondary Possibilities

• Fungal leaf spot: If soil moisture adequate, spray systemic fungicide (propiconazole).
• Herbicide drift: Roundup drift causes marginal necrosis. Symptoms resolve; new growth normal.

Diagnostic Order

1. Verify deep, consistent soil moisture.
2. If moisture good, apply systemic fungicide.
3. Ask neighbors about herbicide use.

Water stress is most probable given widespread dry conditions.