Are pelargoniums and hardy geraniums the same plant?

No — completely different plants, often confused. Pelargoniums (often sold as geraniums in garden centres, especially the red and pink summer bedding pots) are tender perennials from South Africa — they don't survive UK winters outdoors. Hardy geraniums (true Geranium species — the cranesbills) are fully winter-hardy perennials that die back each autumn and return in spring. Quick test: if it's a bright red flowering pot plant for sale in May–June as bedding, it's a pelargonium. If it's labelled with a Geranium species or cultivar name (Rozanne, macrorrhizum, etc.) and sold as a perennial, it's a hardy geranium.

When do I cut back a hardy geranium?

Late June for most varieties — and again in late autumn. After the first flush of flowers fades (typically late June), cut the plant back by half to two-thirds to trigger a second flush of flowers and fresh foliage. Rozanne is the exception — it flowers continuously May–first frost and needs only a light tidy mid-summer. Late autumn (after second flush): cut to 10 cm to tidy the plant for winter. The plant returns each spring from the rootstock.

What's the best hardy geranium for the UK?

Rozanne — Plant of the Centenary 2013, violet-blue saucer flowers from May to first frost, vigorous 50 cm sprawling habit, ideal mid-border. For dry shade: G. macrorrhizum — bombproof ground cover, fragrant foliage, light pink flowers. For woodland edge: G. phaeum Samobor — deep maroon flowers, dark leaf markings. For meadow / cottage style: G. pratense — the wild meadow cranesbill, deep blue. Hardy geraniums have a species for every UK condition.

Will hardy geraniums grow in shade?

Yes — some are shade specialists. G. macrorrhizum (and cultivars Album, Spessart, Czakor) is the toughest dry-shade ground cover available — works under trees and in north-facing positions where most plants fail. G. phaeum (mourning widow) and G. nodosum thrive in deeper shade with regular flower production. G. sylvaticum is happy at woodland edges. Rozanne and sun-loving species (pratense, sanguineum) need at least 4 hours direct sun for best flowering.

Why is my hardy geranium not flowering well?

Three common causes. (1) Too shaded for the species (sun-lovers in shade flower poorly). (2) Needs dividing: clumps over 4–5 years old get congested and flower less — divide in early spring. (3) No mid-summer chop: many varieties flower once in June and look tatty unless cut back in late June for a second flush. Rozanne specifically: should flower continuously — if it's not, check sun levels and clump age.

Are hardy geraniums good for wildlife?

Very — particularly for bees and hoverflies. The open saucer-shaped flowers are accessible to most pollinators. Bumblebees, honeybees, solitary bees, hoverflies all work the flowers. G. pratense (meadow cranesbill) is the most pollinator-rich — naturalises in meadow plantings and supports a wide range of bees. Hardy geraniums also provide dense ground cover habitat for insects and small wildlife at ground level. A hardy geranium border is a quietly productive pollinator garden.

Gerânio-vivaz

Geranium sanguineum

Plante gerânios resistentes na primavera ou no outono, ao sol ou à sombra, em praticamente qualquer tipo de solo — são as plantas perenes mais fiáveis e resistentes para os jardins do Reino Unido, com espécies adaptadas a todas as condições, desde o sol pleno até à sombra seca e às zonas arborizadas. A Rozanne é a mais popular de todas (Planta do Centenário da RHS 2013) — flores em forma de pires, de um azul-violeta claro, desde maio até à primeira geada, num monte extenso de 50 cm. Os gerânios resistentes (RHS H5–H7) não são o mesmo que os pelargónios (muitas vezes chamados de gerânios nos centros de jardinagem) — os pelargónios são plantas de verão delicadas; os gerânios resistentes são plantas perenes totalmente resistentes ao inverno. Corte a planta inteira pela metade após a primeira floração no final de junho para estimular uma segunda floração. Não confunda com a erva-de-são-joão — a erva-de-são-joão selvagem (G. robertianum) auto-semeia-se pelos jardins; arranque as plântulas jovens antes que se espalhem. Fácil, bonita, indestrutível.

View full growing guide →