Culture
Easily grown in average, medium moisture, well-drained soils in full sun to part shade. Tolerates some drought, but prefers humusy, moderately fertile soils with regular and consistent moisture plus good soil drainage. Full sun is best in cool northern summer climates, but some part afternoon shade is appreciated in hot summer climates such as the St. Louis area. Deadheading is tedious for larger plantings and probably unnecessary. Foliage may decline after flowering in hot summer climates, at which point it should be cut back and shaped to revitalize, with additional sporadic rebloom sometimes occurring later in summer. Propagate by division.
Noteworthy Characteristics
Geranium × oxonianum is a fertile hybrid between G. endressii and G. versicolor. Cymes of pink flowers with darker veins bloom from late spring into summer on clumping plants featuring 5-lobed basal leaves.
Genus name comes from the Greek word geranos meaning crane in reference to the fruit which purportedly resembles the head and beak of a crane.
The hybrid name oxonianum refers to Oxford, England.
‘Katherine Adele’ is a vigorous cultivar that reportedly was discovered as a seedling from G. ‘Walter’s Gift’. It grows in a clump to 16” tall and as wide, and features light pink, 5-petaled flowers with dark petal veins and glossy, toothed, deeply-lobed, variegated green leaves with distinctive dark purple-black blotches. Flowers primarily bloom in May and June with a sparser continued bloom sometimes occurring in summer.
Problems
No serious insect or disease problems. Some susceptibility to leaf spots and rust.
Uses
Border fronts or cottage gardens. Mass for ground cover. Edging. Rock gardens.