Pest identification
What's eating my penstemon 'husker red'?
Aphids (blackfly / greenfly)
Signs: Colonies on stems and undersides of leaves; distorted, yellowing foliage and sticky honeydew deposits.
Control: Rub off colonies by hand or spray with insecticidal soap. Encourage ladybirds and lacewings. Avoid excess nitrogen that promotes succulent growth.
Slugs and snails
Signs: Ragged holes in young leaves and emerging shoots at ground level, mainly in spring; slime trails visible.
Control: Apply iron phosphate slug pellets around plants. Lay grit mulch around the crown as a deterrent. Hand-pick after dark in damp conditions.
Leaf and bud eelworm (Aphelenchoides spp.)
Signs: Brown angular patches between leaf veins; distorted buds; worst in warm, wet seasons in poorly ventilated spots.
Control: Remove and bin all affected foliage immediately. Avoid overhead watering. Improve air circulation; there is no chemical remedy available to gardeners.
Keep penstemon 'husker red' pest-free
Healthy plants resist pests best. Get the basics right:
Penstemon 'Husker Red' pests — FAQ
What is eating my penstemon 'husker red'?
Penstemon digitalis 'Husker Red' is one of the toughest penstemons — its burgundy-flushed foliage appears less palatable to many insects. Aphids are the most commonly reported pest. Slugs and snails can damage young growth, and leaf and bud eelworm may cause distortion in wet seasons. Overall pest pressure is low.
How do I get rid of aphids (blackfly / greenfly) on penstemon 'husker red'?
Colonies on stems and undersides of leaves; distorted, yellowing foliage and sticky honeydew deposits. Rub off colonies by hand or spray with insecticidal soap. Encourage ladybirds and lacewings. Avoid excess nitrogen that promotes succulent growth.
How do I get rid of slugs and snails on penstemon 'husker red'?
Ragged holes in young leaves and emerging shoots at ground level, mainly in spring; slime trails visible. Apply iron phosphate slug pellets around plants. Lay grit mulch around the crown as a deterrent. Hand-pick after dark in damp conditions.
How do I get rid of leaf and bud eelworm (aphelenchoides spp.) on penstemon 'husker red'?
Brown angular patches between leaf veins; distorted buds; worst in warm, wet seasons in poorly ventilated spots. Remove and bin all affected foliage immediately. Avoid overhead watering. Improve air circulation; there is no chemical remedy available to gardeners.