Rose Buds Shriveling, Leaves Chewed in Colorado Mountains: Rose Midge + Sawfly

Zone 3–4 Colorado: Shrub rose + 'Hansa' rugosa. Buds shrivel with tiny brown pinholes. Leaves have circular holes, yellow then brown. Rugosa leaves faded yellow-green.

Two Pests at Once

1. Rose Midge: Pinholes at bud base → larvae destroy buds. Systemic insecticide + soil drench.
2. Rose Slugs (Sawfly Larvae): Circular leaf holes, skeletonizing. Insecticidal soap/neem/oil on leaf undersides + base.

Rugosa Yellowing

Rugosas hate chemical sprays/fertilizers. The yellow-green fade may be spray sensitivity or nutrient lockout in alkaline soil. Use only organics.

Resource

Rose Midge details: OSU Rose Midge Guide