Troubleshooting
Foxglove problems — and how to fix them
Foxglove (Digitalis purpurea) is generally forgiving once you match its basics, but a few issues come up again and again. Here is what each one looks like, why it happens, and the fix.
Powdery mildew on rosette leaves
Warm, dry spells stress the first-year rosette, which is then rapidly colonised by powdery mildew (Erysiphe species); water at the base, mulch well, and remove severely affected leaves.
Crown rot / failure to overwinter
Wet, cold soil around the crown in winter kills the rosette, especially on heavy clay — plant in well-drained positions and avoid autumn mulching that contacts the crown.
Aphid infestation on flower spike
Foxglove aphids (Acyrthosiphon cyparissiae) and other species colonise the developing flower spikes in late spring, causing stunted or distorted flowers; knock off with a strong water jet or introduce ladybird larvae.
Prevent foxglove problems before they start
Most foxglove issues are care-mismatch, not bad luck. Dial in the basics:
Foxglove problems — FAQ
Why is my foxglove powdery mildew on rosette leaves?
Warm, dry spells stress the first-year rosette, which is then rapidly colonised by powdery mildew (Erysiphe species); water at the base, mulch well, and remove severely affected leaves.
Why is my foxglove crown rot / failure to overwinter?
Wet, cold soil around the crown in winter kills the rosette, especially on heavy clay — plant in well-drained positions and avoid autumn mulching that contacts the crown.
Why is my foxglove aphid infestation on flower spike?
Foxglove aphids (Acyrthosiphon cyparissiae) and other species colonise the developing flower spikes in late spring, causing stunted or distorted flowers; knock off with a strong water jet or introduce ladybird larvae.