How to Grow Hardy Geraniums
Geranium
Hardy geraniums (cranesbills) are among the most reliable and versatile perennials for UK gardens, thriving in sun or partial shade and almost any soil. Plant in spring or autumn, spacing about 45cm apart, and cut back hard after the first flush of flowers to encourage fresh foliage and a second bloom. Long-flowering varieties such as 'Rozanne' perform from June to the first frosts with minimal care. Divide clumps every three to five years to maintain vigour.
Yearly Lifecycle
Care Essentials
Mulch with compost in spring. Rarely needs additional feeding.
Watch For
- Vine weevil
- Sawfly
- Powdery mildew
- Downy mildew
Companions
Roses, Alchemilla, Lavender, Nepeta
Track your Hardy Geraniums care schedule — pruning, feeding, and seasonal tasks
Start planning freeCare Requirements
☀️ Light
Sun or partial shade; some tolerate deep shade
Grow well in full sun or partial shade. Some species such as G. phaeum tolerate deep shade. Flowering is best in sun but foliage stays fresher in light shade.
💧 Watering
Drought-tolerant once established; water in dry spells
Tolerant of most conditions once established. Water during prolonged dry spells, especially newly planted specimens. Avoid waterlogging on heavy clay.
🌱 Fertilizing
Mulch with compost in spring; avoid rich feeds
Rarely needed. Mulch with garden compost in spring to improve soil structure. Avoid rich feeds which produce lush, floppy growth.
✂️ Pruning
Cut back hard after first flush for a second bloom
Cut back hard after the first flush of flowers to near ground level. Fresh foliage and a second wave of flowers follow within weeks. Remove dead foliage in late autumn.
Growing Tips
Chelsea chop for a second flush
After the first flush fades, cut the whole plant back hard to near ground level. Fresh leaves and a second wave of flowers follow within weeks.
Versatile in sun or shade
Hardy geraniums grow in sun or shade and tolerate most soils. Use them under roses, along path edges, or as ground cover.
Divide every few years
Lift and divide congested clumps in spring or autumn. Replant the healthiest outer portions and discard the woody centre.
Watch for vine weevil
Check for vine weevil damage — notched leaf edges and wilting plants. Use biological nematode controls in late summer.
Pests & Diseases
Pest Vine Weevil
Identification: Notched leaf edges from adult feeding at night; wilting and collapse from root-feeding larvae in pots
- Apply Heterorhabditis nematodes to compost in late summer
- Check root balls when repotting and destroy cream-coloured C-shaped larvae
- Drench containers with acetamiprid-based vine weevil killer
Pest Geranium Sawfly
Identification: Pale green caterpillar-like larvae eating holes in leaves; skeletonised foliage in severe cases
- Pick off larvae by hand when spotted
- Cut back affected plants hard — fresh growth replaces damaged foliage quickly
- Contact pyrethrin spray on visible larvae
Pest Slugs and Snails
Identification: Irregular holes in leaves; slime trails on and around plants; damage worst overnight and in wet weather
- Apply biological nematode control (Phasmarhabditis hermaphrodita) in spring
- Use copper tape around containers; set beer traps
- Ferric phosphate slug pellets (wildlife-safe)
Disease Powdery Mildew
Symptoms: White powdery coating on leaves and stems; affected leaves may yellow and drop
Treatment: Cut back affected growth hard — fresh foliage usually comes through clean
Prevention: Ensure good air circulation; avoid overcrowding; water at the base
Disease Downy Mildew Peronospora spp.
Symptoms: Yellow patches on upper leaf surfaces with greyish-purple downy growth underneath; leaves may brown and collapse
Treatment: Remove and destroy affected leaves; improve air circulation
Prevention: Avoid overhead watering; space plants for good airflow; clear fallen debris
Popular Varieties
Rozanne, Johnson's Blue, Orion, Patricia, Wargrave Pink, Biokovo
Log Hardy Geraniums in your garden — track growth, care, and harvests year after year
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