Rose Buds Drying and Dropping? It’s Likely Rose Midge

If your 10-year-old ‘Thérèse Bugnet’ roses in Alberta are losing buds before they open, the tiny rose midge (Dasineura rhodophaga) is the prime suspect. Adult midges emerge in spring, lay eggs in flower buds, and larvae feed inside, causing buds to blacken, distort, and drop. The cycle repeats every two weeks from May through September.

Immediate Control Steps

• Prune and destroy all affected buds weekly—seal in a plastic bag, don’t compost.
• Lay landscape fabric under the bushes in early spring to block emerging adults and prevent larvae from pupating in soil.
• Monitor with yellow sticky traps near the canopy.

Chemical Options (If Needed)

For severe infestations, apply a systemic insecticide containing imidacloprid or spinosad at bud break, following label directions. Avoid spraying during bloom to protect pollinators. Consistent sanitation and fabric barriers usually bring midge populations down within a season.