Lovely agapanthus (Lily of the Nile) is native to South Africa and is not reliably hardy in the Southern Appalachian region (zones 6 – 7). Many small tubular flowers comprise each ball -shaped (umbel) flower cluster. Tall sturdy floral scapes rise 1 to 4 feet in height, blooming from late spring into late summer depending on the cultivar. Many cultivars are available in shades of blue, purple and white.
In this region, agapanthus may be dependably grown in outdoor landscape planters which are brought inside in the fall. Agapanthus has multiple cultural issues: cold hardiness, wet wintry soils and hungry voles. Further south in zone 7-b, the crown may be covered over with several inches of leaves or mulch in late fall. The mulch is removed once the threat of spring frost has passed.
Agapanthus produces attractive glossy, strap-like green leaves, which grow from its fleshy tuberous roots. It is propagated by division of the root clumps immediately after flowering. Divide vigorous clumps every 2 to 3 years in early spring.
Agapanthus prefers a well-drained, fertile, slightly acidic soil. Locate the plant in a warm, sheltered spot under partial sun. Space plants 24 inches apart with its shallow surface roots barely visible on the ground.
Don’t permit agapanthus to dry out. Weekly watering encourages a deep extensive root system. Soggy soil is never good; the leaf tips turn yellow in a waterlogged soil.
Agapanthus requires light constant feeding in the spring and summer months using either water-soluble or slow release fertilizer with a 10-20-20 ratio. In the fall stop feeding and reduce watering to induce plant dormancy.
Pruning is done sparingly, usually to remove damaged or dead foliage before new leaves emerge in the spring.
Mealybug , red spider mite, and voles may become significant pest/critter problems.