Troubleshooting
Prairie Beardtongue problems — and how to fix them
Prairie Beardtongue (Penstemon cobaea) 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.
Root and crown rot
Wet, heavy, or poorly drained soils — especially during winter dormancy — cause fatal root and crown rot; plant in sharply drained, lean soil and avoid any irrigation during wet winters.
Powdery mildew
Fungal powdery mildew can appear on foliage in humid, poorly ventilated spots; improve air circulation by spacing plants adequately (at least 30 cm apart) and avoid overhead watering.
Prevent prairie beardtongue problems before they start
Most prairie beardtongue issues are care-mismatch, not bad luck. Dial in the basics:
Prairie Beardtongue problems — FAQ
Why is my prairie beardtongue root and crown rot?
Wet, heavy, or poorly drained soils — especially during winter dormancy — cause fatal root and crown rot; plant in sharply drained, lean soil and avoid any irrigation during wet winters.
Why is my prairie beardtongue powdery mildew?
Fungal powdery mildew can appear on foliage in humid, poorly ventilated spots; improve air circulation by spacing plants adequately (at least 30 cm apart) and avoid overhead watering.