Pest identification
What's eating my geranium himalayense 'plenum'?
Vine weevil
Signs: Grubs consume rhizomes and roots causing plant collapse; adult beetles notch leaf margins at night.
Control: Nematode soil drench in late summer; examine rhizomes carefully at division time and remove any grubs.
Slugs and snails
Signs: Irregular holes and ragged leaf margins; worst on young spring growth and in wet weather.
Control: Use ferric phosphate pellets around the crown; apply a grit mulch; hand-pick at night.
Aphids
Signs: Colonies on shoot tips producing honeydew and minor leaf distortion on new growth.
Control: Blast off with water or apply insecticidal soap; tolerate low numbers aided by natural predators.
Keep geranium himalayense 'plenum' pest-free
Healthy plants resist pests best. Get the basics right:
- What eats geranium himalayense — the species this cultivar belongs to
- What's wrong with my plant? — the diagnosis apps compared
- Common geranium himalayense 'plenum' problems & fixes
- Geranium himalayense 'Plenum' watering schedule
- Geranium himalayense 'Plenum' light requirements
- Full geranium himalayense 'plenum' care guide
Geranium himalayense 'Plenum' pests — FAQ
What is eating my geranium himalayense 'plenum'?
Geranium himalayense 'Plenum' (syn. 'Birch Double') is a compact, double-flowered cultivar sharing the species' low pest susceptibility. Vine weevil grubs attacking rhizomes are the greatest risk. Slugs and snails can damage foliage in wet conditions, and aphids may colonise shoots in spring. Strong rhizomes aid recovery from minor damage.
How do I get rid of vine weevil on geranium himalayense 'plenum'?
Grubs consume rhizomes and roots causing plant collapse; adult beetles notch leaf margins at night. Nematode soil drench in late summer; examine rhizomes carefully at division time and remove any grubs.
How do I get rid of slugs and snails on geranium himalayense 'plenum'?
Irregular holes and ragged leaf margins; worst on young spring growth and in wet weather. Use ferric phosphate pellets around the crown; apply a grit mulch; hand-pick at night.
How do I get rid of aphids on geranium himalayense 'plenum'?
Colonies on shoot tips producing honeydew and minor leaf distortion on new growth. Blast off with water or apply insecticidal soap; tolerate low numbers aided by natural predators.