Troubleshooting
Nettle-leaved Mullein problems — and how to fix them
Nettle-leaved Mullein (Verbascum chaixii) 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
Can occur in humid, crowded conditions, especially later in summer. Plant in open, sunny spots with good airflow. Generally cosmetic; cut affected foliage back after flowering.
Verbascum moth caterpillars (Cucullia verbasci)
Yellow-and-black patterned caterpillars strip foliage and flowers in early summer. Hand-pick to control; plants usually recover and reflower if damage occurs before peak bloom.
Crown rot in winter wet
Even the perennial V. chaixii resents prolonged wet at the crown. On heavy soils, incorporate grit at planting or mulch around (not over) the crown with gravel.
Prevent nettle-leaved mullein problems before they start
Most nettle-leaved mullein issues are care-mismatch, not bad luck. Dial in the basics:
Nettle-leaved Mullein problems — FAQ
Why is my nettle-leaved mullein powdery mildew?
Can occur in humid, crowded conditions, especially later in summer. Plant in open, sunny spots with good airflow. Generally cosmetic; cut affected foliage back after flowering.
Why is my nettle-leaved mullein verbascum moth caterpillars (cucullia verbasci)?
Yellow-and-black patterned caterpillars strip foliage and flowers in early summer. Hand-pick to control; plants usually recover and reflower if damage occurs before peak bloom.
Why is my nettle-leaved mullein crown rot in winter wet?
Even the perennial V. chaixii resents prolonged wet at the crown. On heavy soils, incorporate grit at planting or mulch around (not over) the crown with gravel.