This is a family of, perennials and shrubs, both deciduous and evergreen. Some are hardy, others tender. The large saucer or funnel-shaped last only for a day.
Suitable site and soil. Grow in any ordinary or even poor, well-drained soil in a sunny, well protected from cold winds. Rock gardens and banks are suitable for smaller varieties. Grow climbing forms over walls, fences, arches, a trellis or a hedge alone or with other climbers.
Cultivation and care. Dead-head frequently for continuous flowering from early summer through to the autumn.
Propagation. Theof should be sown under glass in . Early spring is the best time to do this, and John Innes compost is sufficient. You can also wait until mid-spring to the seeds in the site chosen for flowering. Take heel of shrubby and perennial species in summer. Overwinter in a cold frame, if you have one, and plant out the following spring.
Recommended varieties. C. tricolor (also known as C. minor) is a fast-growing hardy(height 30cm – 12in; spread 30-40cm – 12-16in) with blue flowers with yellowish throats. C. cneonim is a half-hardy evergreen shrub with pink buds opening to white flowers. (Height and spread 60-90cm – 2-3ft.) C. althaeoides is a prostrate perennial with silvery green and pale pink flowers.
Pests and diseases. Generally trouble free.
A SUNNY BANK
Like its fast growing cousin, morning glory (ipomoea), C. althaeoides will creep if it is not supported. If you have a dry sunny bank with poor soil, C. althaeoides will quickly clothe it in pale pink flowers from summer to autumn transforming an otherwise barren part of the garden. In order to make sure the bank is covered all year round grow it with an evergreen such as purple aubrieta which begins flowering in spring and will blend with the pink convolvulus in summer.