Pelargonium

Pelargonium peltatum, the ivy-leaved geranium, is a trailing, semi-succulent evergreen perennial from the Cape region of South Africa, grown worldwide for the cascading mauve-to-pink-to-white flower clusters it carries over fleshy, five-lobed, ivy-shaped leaves. Its scrambling stems (to about 6.6 feet in the wild) make it the classic plant for hanging baskets, window boxes, and balcony planters, where it spills and blooms from spring through summer. It is genuinely frost-tender - RHS rates it H2 (hardy only to about 34 to 41°F), so outside roughly USDA zones 9b-11 it is treated as a container or annual plant and overwintered indoors before the first autumn frost. Unlike the toxic bulbs of some other South African ornamentals, this pelargonium is not one of those poisonous bulbs and its young buds and leaves are even traditionally eaten by people; note, however, that like other pelargoniums it is regarded as mildly toxic to pets (cats and dogs), so keep grazing animals away from it. It demands full sun and sharp drainage, tolerates drought, but will not take shade or freezing. In Mediterranean climates (California, Spain, Portugal, Greece) it has naturalized, so site it thoughtfully where winters are mild.

A tender, bushy evergreen subshrub from southern Africa grown almost everywhere for one reason: its deeply lobed, soft, gray-green leaves release an intense rose-with-a-hint-of-mint fragrance the moment you brush or pinch them. The honest point to get right up front is the name. This is a Pelargonium, not a hardy true Geranium (cranesbill) - the two are routinely confused because 'geranium' was attached to both centuries ago, but Pelargonium graveolens is frost-tender, while the perennial border geraniums most gardeners know are cold-hardy. Across most of North America it is grown as a warm-season annual, a patio container plant, or a houseplant overwintered indoors, not as a permanent landscape shrub. The small pinkish flowers are insignificant; the aromatic foliage is the entire point, and it is also the commercial source of rose-geranium essential oil and a kitchen herb for scenting teas, sugar, baked goods, and jellies.

The classic bedding "geranium" - a tender hybrid of South African Pelargonium parentage grown for rounded umbels of red, pink, orange, purple, or white flowers that bloom freely all season. Its rounded, kidney-shaped leaves often carry a dark circular band, the "zone" that gives the plant its name. Hardy only in USDA zones 10-11, it is grown as an annual or overwintered indoors across most of North America.