Troubleshooting
Penstemon 'Raven' problems — and how to fix them
Penstemon 'Raven' (Penstemon 'Raven') 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.
Winter wet kills more than cold
Waterlogged soil in cold winters is the leading cause of loss. Grow in free-draining ground and delay cutting back until spring to protect the crown.
Fewer flowers if not deadheaded
Leaving spent spikes slows reblooming. Deadhead through the season and site in full sun for continuous colour into autumn.
Powdery mildew
A white film forms in damp, crowded conditions. Space plants well, improve airflow and water at the base.
Woody, short-lived clumps
Plants grow woody and flower less after a few years. Renew regularly from cuttings to maintain a strong display.
Prevent penstemon 'raven' problems before they start
Most penstemon 'raven' issues are care-mismatch, not bad luck. Dial in the basics:
Looking for penstemon 'raven' in general rather than its problems? Read the full penstemon 'raven' care guide — light, water, soil and feeding.
Penstemon 'Raven' problems — FAQ
Why is my penstemon 'raven' winter wet kills more than cold?
Waterlogged soil in cold winters is the leading cause of loss. Grow in free-draining ground and delay cutting back until spring to protect the crown.
Why is my penstemon 'raven' fewer flowers if not deadheaded?
Leaving spent spikes slows reblooming. Deadhead through the season and site in full sun for continuous colour into autumn.
Why is my penstemon 'raven' powdery mildew?
A white film forms in damp, crowded conditions. Space plants well, improve airflow and water at the base.
Why is my penstemon 'raven' woody, short-lived clumps?
Plants grow woody and flower less after a few years. Renew regularly from cuttings to maintain a strong display.