Agapanthus grow well in containers and this enables easier winter protection. Keep plants in a cool, bright position, avoiding both excessively wet or dry conditions. More tender species of agapanthus are ideal candidates for growing in pots, as they can easily be positioned to view them at their best, then moved to shelter indoors over winter.
Agapanthus (African lilies) are herbaceous perennials, with thick, fleshy, rhizomatous rootstocks. Tender evergreen species such as A. africanus and smaller deciduous hybrids including A. ‘Blue Moon’ or A. ‘Castle of Mey’ are ideal for containers, especially where garden soils are prone to winter waterlogging. Grow single plants in a 20-23cm (8-9in) diameter container, and multiple-crown plants in a large, deep pot so that they can be left undisturbed for several years before potting on using John Innes No 2 or No 3 compost.
Care for container plants
Feed established plants weekly or fortnightly with a dilute balanced liquid feed during the growing season until the flowers begin to show colour. Water freely when in growth, but sparingly in winter.
In late autumn remove containers of evergreen Agapanthus from the garden and place in a light, dry, frost-free location such as a cold frame, glasshouse or conservatory. Hardier species may be left outdoors in milder areas, with the shelter of a wall for protection and avoiding excessive winter wet. Do not place in a warm position as any winter growth is detrimental to the health of the plant and may reduce flowering. Give those in open ground a dry mulch in autumn or early winter.
Dividing plants will lead to a reduction in flowering. Most plants will only need dividing every four to six years or once flowering begins to deteriorate.
Please note: The roots of Agapanthus contain saponins, which can cause severe irritation to skin and abdominal contractions, so wear gloves when handling plants.
William Denne