Troubleshooting
Great Mullein problems — and how to fix them
Great Mullein (Verbascum thapsus) is generally low-drama, but a few issues come up again and again. Here is what each one looks like, why it happens, and the fix.
Mullein moth caterpillars (Cucullia verbasci)
Yellow, black, and white spotted caterpillars can skeletonise leaves rapidly; hand-pick caterpillars promptly as they are rarely numerous enough to warrant chemical control.
Crown rot in wet soils
The woolly crown rots quickly in waterlogged or poorly drained ground; always plant in an open, sunny position with free-draining soil and avoid overhead watering.
Prevent great mullein problems before they start
Most great mullein issues are care-mismatch, not bad luck. Dial in the basics:
Great Mullein problems — FAQ
Why is my great mullein mullein moth caterpillars (cucullia verbasci)?
Yellow, black, and white spotted caterpillars can skeletonise leaves rapidly; hand-pick caterpillars promptly as they are rarely numerous enough to warrant chemical control.
Why is my great mullein crown rot in wet soils?
The woolly crown rots quickly in waterlogged or poorly drained ground; always plant in an open, sunny position with free-draining soil and avoid overhead watering.