Hardy Geraniums

Geranium Johnson's Blue

A large family of mainly herbaceous hardy perennials, although a few annual forms are available. They make good ground cover and provide a very long season of brightly coloured blooms, in various shades of blue, pink, purple or violet.

Not to be confused with tender Pelargoniums - also commonly known as geraniums.

Family: Geraniaceae
Botanical Name: Geranium
Common Names: Crane's-bill, cranesbill, crowfoot, bassinet, king's hood, wood geranium

Foliage: Deciduous, mid-green or grey-green leaves. Rounded, deeply lobed or divided. Some varieties provide good autumn colour.

Flowers: Flat, rounded, five petalled flowers, in shades of white, pink, red, purple, blue and violet (depending on variety).

Flowering Period: Late spring onwards.

Soil: Moist but well-drained, poor soil (chalk, clay, sand or loam). Any pH.

Conditions: Full sun or partial shade. Can be planted in any aspect, in either an exposed or sheltered possition.

Habit: Rhizomatous, mat-forming.

Type: Herbaceous perennial.

Hardiness: Most varieties are fully hardy in the UK.

Planting and Growing Geraniums

Plant out during autumn or spring. Hardy geraniums are very easy to grow. They thrive in any kind of well drained soil, that is not too dry; requiring very little care and attention once established.

Excellent for the front or middle of the flower border or a lightly shady spot. A good choice for cottage or wildflower gardens.

Many vigorous forms provide excellent ground cover and weed suppression. Dwarf varieties are suitable for the rock garden. These perform best in poor, sandy or gritty soil.

Most varieties are shade tolerant but will flower best in an open sunny position.

The single open flowers attract pollinators and other benificial insects.

Taking Care of Geraniums

A second flush or flowers can often be encouraged by cutting back old flowering stems to just above the soil level.

Pruning Geranium

Cut down the dead stems of tall species in the autumn.

Pests and Diseases

Generally disease free. Susceptible to attack by slugs, capsid bug, sawflies and vine weevil.

Propagating Geraniums

They can be propagated from seed but are easily increased by division in spring. Alternatively, take cuttings of matured side-shoots in August.

Popular Varieties of Hardy Geranium

Geranium cantabrigiense is a popular cottage garden form. Cultivar 'Biokovo' has has evergreen foliage and and dusty pink flowers in summer. The autumn the foliage changes to shades of red and bronze. Available from Van Meuwen.

Geranium endressii is a semi-evergreen perennial that provides mounds of colour in sun or part shade. Height to 20in (50cm), spread to 40in (100cm). Available at Thompson and Morgan.

Geranium 'Johnson's Blue' is a very popular border variety with blue-mauve flowers in mid summer. Deeply lobed leaves. Height to 24in (60cm). Available at Gardening Express.

Geranium macrorrhizum is a rapid spreading carpeter. The rich green leaves turn scarlet in autumn. Magenta or rose-pink flowers. Height to 12in (30cm).

Geranium x oxonianum is a good sturdy variety, usually grown in full sun though it can tolerate light shade. Good cultivars include 'Claridge Druce' (pink), 'Cream Chocolate' (dark brown markings on the leaves) and 'wargrave pink', which is a vigorous spreader that produces waves of bright salmon-pink flowers from summer and into autumn. Height to 2ft (60cm). Available at Thompson and Morgan.

Geranium pratense (meadow or common cranesbill) is a very attractive and decorative species that produces open saucer-shaped blooms in shades of white, blue or violet, from early to mid-summer. A wide range of cultivars are available, some with very dark leaves and others with double flowers. These include, 'Dark Reiter' (dark, deeply dissected, filigree foliage with violet flowers) available at Gardening Express. Also 'Midnight Reiter' (dark black-burgundy leaves with deep violet flowers), 'Mrs Kendal Clark' (tall form with large finely-divided foliage and lilac-blue flowers), 'Splish Splash' (large flowers splashed with violet-blue over a white background), 'Summer Skies' (soft sky blue double flowers) and 'Cloud Nine' a new from with lilac blue, double flowers. Available at Thompson and Morgan.

Geranium psilostemon is a midsummer flowering tall form with bright magenta flowers with dark centres. Height to 2.5ft (75cm).

Geranium Rozanne 'Jolly Bee' is a large mounding Geranium with large bright blue flowers that bloom from summer until the first frosts. Available at Gardening Express.

Geranium sanguineum (Bloody Cranesbill) is vibrant pink form, ideal for the rock garden, crazy paving or as path edging. Long flowering season. Good cultivars include: 'Album' (star-shaped pure-white flowers) 'Max Frei' (deep carmine magenta-purple) and 'striatum' (light pink). Available at Gardening Express.

Geranium sylvaticum (Wood Cranesbill) is ideal for light shade, providing masses of violet-blue early summer colour. Good cultivars include: 'Mayflower', with light purple flowers, fading to violet-blue. Available at Gardening Express.

Geranium transversale is a compact mound forming type that provides excellent ground cover. Good cultivars include 'Foundling's Friend' which has intricate patterning on its many pink blooms. Available at Thompson and Morgan.