There are about 26 species of Nerine, native to Southern Africa. All have six narrow petals recurved at the tips with prominent stamens. The leaves are usually strap-like, appearing with or after the flowers.
Nerine bowdenii is hardy outside while N. sarniensis (Guernsey lily) and its hybrids are suited to greenhouse or conservatory cultivation.
Nerine bowdenii can be planted outdoors in well-drained soil in a sunny, sheltered position in open borders or at the foot of a wall. They will not flower in shaded situations and do not compete well with other garden plants. They are also suitable for container cultivation.
Ideally plant bulbs 10cm (4in) apart with the neck of the bulb just exposed. However, in cold areas plant 5cm (2in) deep to help protect from frost. Leaves appear in spring then die down naturally at the end of summer. Flowers follow in the autumn. Bulbs in the ground should be left undisturbed until they become crowded and flowering declines.
Nerine undulata Flexuosa Group can also be grown outdoors in the UK but flowers even later than N. bowdenii (November-December) making it susceptible to weather damage and slugs. Nerine filifolia may be grown outdoors in warmer regions.
Nerine sarniensis (Guernsey lily) and its hybrids are best suited to container cultivation in a frost-free greenhouse or conservatory with a minimum winter temperature of 7°C (45°F). Use an open, free-draining growing media made up of equal amounts of John Innes No.3, multipurpose compost and gritty sand. Do not over-pot bulbs. A 10cm (4in) pot is suitable for a single bulb. In larger containers space bulbs close but not touching. Plant with the neck of the bulb just exposed.
Water moderately as the flower spike emerges in autumn and increase as the stem and, later, the leaves develop over winter. From January to April feed every two weeks with a potassium-rich liquid feed such as a tomato feed. Cease watering once the foliage begins to yellow. Keep plants slightly dry during their dormant summer period but, contrary to opinion, they do not like to be ‘baked’ in summer. Repot on a regular basis at the end of summer.