The common indoor/outdoor plant most people know as geranium is, botanically, Pelargonium. Considered here are true geraniums, which are mostly hardy plants. Many types bloom over a long period, bearing flowers that are attractive though not always as showy as those of pelargoniums. Carried singly or in few-flowered clusters, blossoms have five overlapping petals that look alike. (Pelargonium flowers also have five petals, but two point in one direction, while the other three point in the opposite direction.) Colors include blue, purple, magenta, and bluish rose; some are pure pink or white. Beak-like fruit that follows the flowers accounts for the common name “cranesbill.” Leaves are roundish or kidney-shaped, lobed or deeply cut; plants may be upright or trailing.
Good in rock gardens and perennial borders; some are useful as small- or large-scale groundcovers. A few shrubby species are good for holding slopes. Best climates for most geraniums are cool- and mild-summer regions, where the plants can grow in full sun or light shade. In hot-summer areas, give afternoon shade. South African species are less cold-hardy but are more tolerant of heat and afternoon sun. All species appreciate moist, well-drained soil.
Some geraniums benefit from being cut back after flowering or in the fall. Clumps of most types can be left in place for many years before they decline due to crowding; at that point, divide in early spring. Increase by transplanting rooted portions from a clump’s edge; or take cuttings. Many produce lots of seedlings, and some can become naturalized pests.Geranium cinereum
From the Pyrenees. Forms wide, 8–12-in.-tall mats composed of 1–1 1/2-in., soft gray-green leaves that are rounded, bluntly lobed, and deeply cut. In early to midsummer, slender, trailing stems bear many cupped, 1–1 1/2-in.-wide flowers in pale pink with dark veins.
‘Ballerina’: Pinkish lilac flowers with dark veins radiating from a wine-colored center; continues blooming into fall.
‘Laurence Flatman’: Slightly larger than the species. Light lavender blossoms display reddish central blotches between red veins.
Himalayan native to 1 1/2 ft. high, spreading by rhizomes. Long-stalked, medium green, 2 1/2-in.-wide leaves are roundish, with prominent veins and five broad, deeply divided lobes. Blooms from late spring into summer; 1-ft. stems bear clusters of 1 1/2–2-in.-wide blue flowers with reddish veins and a purple eye. Excellent deciduous small-scale bulb cover; plant 1–1 1/2 ft. apart.
From South Africa. Grows to 6–10 in. high, spreading fast to form a 2-ft.-wide cushion of finely cut leaves. Inch-wide light magenta flowers appear from spring to fall. Cut to the ground every 2 or 3 years in late fall to keep plants neat.
Endures heat and drought better than most geraniums, but needs some summer water. Self-seeds profusely and can be invasive.
From southern Europe. Grows to 8–10 in. high, spreading fast by underground rootstocks and fleshy rhizomes that root on the soil surface. Thick, hairy, sticky, five- to seven-lobed leaves are 3–4 in. across; foliage has a strong, musky fragrance and attractive autumn coloring ranging from dull yellow to orange and scarlet. Inch-wide flowers in white, pink, or magenta. Blooms late spring through early summer; some repeat in fall. Good groundcover for small areas, though it can overwhelm smaller plants. Succeeds in dry shade.
‘Ingwersen’s Variety’ has soft bluish pink flowers and a long blooming season.
Dramatic native of Madeira likes moist conditions and shade. Has the largest of all geranium leaves (to 2 ft. long)—overlapping, glossy, deeply divided, shaped like giant snowflakes. Reddish brown leafstalks help buttress the 3–4-ft. “trunk” supporting hundreds of densely packed, fuzzy buds and magenta-eyed deep pink blossoms to 1 1/2 in. wide. Blooms early spring through midsummer. Biennial or short-lived perennial; dies after blooming but spawns many seedlings.
Shade-loving native of southern and central European mountains. Grows to 2 ft. tall and 1 1/2 ft. wide. Leaves are basal, 3–4 in. across, shallowly cut into seven to nine tooth-edged lobes, often with brown markings. Clusters of dusky purple or maroon blossoms rise above a foliage mass from spring to fall. Cut back flowering stems after bloom to neaten appearance and encourage rebloom. Excellent with ferns in a woodland garden. ‘Samobor’ has light maroon flowers and leaves with distinctive maroon markings.
Native from Ireland to Siberia and Japan. Forms a clump to 1 1/2–2 ft. tall and 2– 3 ft. wide. Hairy, 3–6-in. leaves on upright stalks are deeply cut into seven narrow, pointed, divided lobes. Flowers are about 1 in. wide, typically blue with reddish veins; blooms from spring through summer. Self-seeds profusely; cut to the ground when flowers fade to prevent seedlings and encourage rebloom. ‘Mrs. Kendall Clark’ has pale blue flowers with lighter veins.
From the Caucasus. Compact grower to 1 ft. high and wide. Velvety gray-green leaves have deeply etched veins and scalloped lobes. Early to midsummer flowers are white with violet veining; overall effect is pearly gray. May be cut back hard in the fall.
Native from western Europe to the Caucasus and Turkey. Forms a dense clump 8–18 in. high, spreading by rhizomes to 2 1/2 ft. or wider. Dark green, 1–2-in.-wide leaves are deeply divided into five to seven lobes, each with three narrow segments; turn blood red in fall. Typical forms have deep purple to almost crimson flowers 1 1/2 in. wide; bloom late spring well into summer and will rebloom if cut to the ground.
Good 1–1 1/2-ft.-tall selections include white ‘Album’; ‘John Elsley’, pink with deeper pink veins; and reddish purple ‘Max Frei’.
G. s. striatum is a ompact subspecies that grows to only 5–6 in. high. Bears light pink flowers heavily veined with red (its seedlings may vary somewhat) and makes an excellent rock garden or foreground plant.Geranium subcaulescens
Native to the Balkans and Turkey. Like G. cinereum (8–12-in. tall with a spreading mat of leaves), but with darker green leaves and brilliant crimson-magenta flowers with black centers and veins.
Excellent groundcover, 6–8 in. high, spreading slowly but widely. Pleasantly scented, dark green leaves are 1 1/2–2 1/2 in. wide and deeply cut with multiple lobes. Long-lasting flowers are about 1 in. across. Plants may be sheared in late fall for fresh spring growth.
‘Biokovo’ is a popular variety that has white blooms with a pale pink blush.Geranium x oxonianum
Among the best selections of this hybrid group is ‘Claridge Druce’, which forms a vigorous clump to 2–3 ft. high and 3 ft. wide. Rounded leaves are deeply cut. Funnel-shaped, broad-petaled, 1 1/2-in., cool pink flowers with purplish veins bloom late spring to summer. A good large-scale groundcover but can overwhelm adjacent plants. Self-sows profusely; seedlings resemble the parent, but blossoms often have narrower petals.
Cut back hard after flowering to encourage fresh foliage and discourage reseeding. ‘Wargrave Pink’ is similar but a little less vigorous, with glossy warm pink blossoms that resemble those of G. endressii (one of the parents). ‘Winscombe’ has flowers that open pale pink and turn deep pink with age, giving an overall multicolored effect.Geranium ‘Ann Folkard’
Mounding, billowing plant (to 1 1/2 ft. high and 5 ft. wide) with chartreuse leaves that age to light green. Saucer-shaped, 1 1/2-in.-wide blossoms are rich magenta-purple suffused with pink and blue, centered and veined in black. Blooms from spring into fall. Effective planted at the edge of a patio and sprawling onto it.
Hybrid developed by crossing G. pratense and a purple form of G. clarkei. Grows to 2 1/2 ft. tall and as wide, with deeply serrated, 3-in.-wide leaves. Plant is covered from late spring into summer with bowl-shaped flowers to 2 in. across. Long-lasting blooms are rich, deep blue with pale centers and pink veins. Its seedling ‘Orion’ is similar, but with larger flowers of an even richer blue. Both can be cut back after flowering for repeat bloom.Geranium ‘Johnson’s Blue’
Popular hybrid resembling its G. himalayense parent, but its leaf divisions are narrower. Mounds 1 1/2–2 ft. tall and spreads by rhizomes to 2–3 ft. wide. Excellent summer groundcover. Abundant 2-in., blue-violet flowers in loose clusters from spring to fall. Blossoms are sterile.
Much of the material sold under this name is ‘Gravetye’ or another G. himalayense form, with a shorter bloom season and fertile flowers.Geranium ‘Pink Spice’
Compact mound to 8–10 in. tall and 1 ft. wide. Reddish bronze, 1 1/2-in. leaves form a dark background for inch-wide pink blossoms on long, trailing stems. Blooms from late spring through fall. Foliage color is best with at least half-day direct sun. Ideal for a rock garden or spilling from a container.
This naturally occurring hybrid between G. himalayense and G. wallichianum ‘Buxton’s Variety’ is very popular and easy to grow. It is heat-tolerant and blooms best in a sunny spot. Plants reach 1 1/2–2 ft. tall and spread a little wider, forming a lush mound of deeply lobed, 2-in.-wide medium green leaves with attractive chartreuse mottling; foliage takes on red tones in the fall. Stunning flowers, to 2 1/2 in. wide, are rich violet-blue with a large white eye.
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