How to grow Erodium
From the Greek erodios, a heron; the style and ovaries resemble the head and beak of a heron (Geraniaceae). Heron’s bill. Hardy perennials, closely related to the hardy geraniums, or crane’s bills. There are dwarf species suitable for the rock garden and taller border plants.
Species cultivated E. absinthoides, 1 foot or more, violet, pink or white, summer, south-east Europe, Asia Minor; var. amanum, 6 inches, white, leaves hairy white. E. chamaedryoides (syn. E. reichardii), 2 inches, white, veined pink, June, Majorca; var. roseum, deep pink. E. chrysanthum, 6 inches, soft yellow flowers, summer, grey-green, ferny leaves, Greece. E. corsicum. mat-forming, rosy-pink withdeeper veins, summer, Corsica; vars. album, white, rubrum, clear red. E. x kolbianum, 3 inches, white to pink, summer, hybrid. E. loderi, 4-6 inches, white or pale pink, summer. E. macradenum, 6 inches, violet, blotched purple at base, summer, Pyrenees. E. manescavii, up to 2 feet, wine-red, summer, Pyrenees. E. pelargoniflorum, 1 foot, white, marked purple, summer, Anatolia. E. supracanum, 4 inches, white, veined pink, summer, Pyrenees.
Cultivation Plant out the taller varieties in March or April in ordinary soil and in a sunny position. These plants dislike acid soils. They very seldom need transplanting, although pot grown alpine species should be repotted in April every year, in a compost of equal parts of loam, leafmould, and sharp sand. Propagation is by seed sown in March or April for the taller species in a temperature of 55°F (13°C) and in July or August in a cold frame for the alpine species. Plants may be divided in April, and cuttings of dwarf species for the rock garden may be taken in May. The cuttings should then be rooted in a sandy soil, in a frame.