Nerine

A South African bulb producing elegant umbels of glistening pink flowers with curled, spider-like petals that sparkle in autumn sunshine. Nerine blooms best when crowded and baked against a sunny wall, and resents being disturbed once established. The flowers appear on bare stems before the leaves and are outstanding for cutting.

Nerine can be grown from seed, which is best sown fresh as soon as it ripens, typically in early winter. The fleshy seeds should be pressed into moist, gritty compost but not covered. Keep at cool room temperatures and maintain even moisture. Seeds germinate within four to eight weeks. Grow seedlings on without a dormant period for their first two years, feeding regularly. Plants from seed typically take four to six years to reach flowering size and may show variation in flower color.

Plant nerine bulbs in spring, with the neck of the bulb just above soil level, spacing them six inches apart. Choose a hot, sunny position at the base of a south or west-facing wall where the bulbs will receive maximum summer warmth, which is essential for initiating flower buds. Nerine bowdenii is the hardiest species and can be grown outdoors in zones 7 to 10 with good drainage and winter protection.

During spring and summer, nerine foliage is actively growing and the bulbs need regular moisture. Feed every two weeks with a high-potassium liquid fertilizer from when the leaves are fully developed until they begin to yellow. As foliage dies back in late summer, stop watering and feeding. The dramatic pink flower stems emerge from bare ground in autumn, followed by fresh leaves after flowering.

Nerine blooms best when congested and undisturbed, so resist the urge to divide clumps too frequently. Allow bulbs to become crowded in their planting position, only dividing when flowering noticeably declines after five to seven years. In marginal areas, apply a dry mulch of straw or bark chips in late autumn after flowering to protect the bulbs through winter. Remove the mulch in spring as new foliage emerges.

Nerine's late autumn flowering makes it a perfect partner for other fall-blooming plants such as colchicum, cyclamen hederifolium, and autumn crocuses. The hot-wall position it requires can be shared with other sun-loving bulbs like agapanthus and amaryllis belladonna. Low-growing silver-foliaged plants like artemisia and santolina provide attractive groundcover around the bulbs during their dormant and growing periods.

Nerine requires well-drained soil in a hot, sunny position with a pH of 6.0 to 7.5. Sandy or gravelly soil at the base of a warm wall is ideal. Amend heavy clay with generous quantities of grit and sand. Apply bone meal at planting time and feed with high-potassium liquid fertilizer fortnightly during the growing season. The summer baking period is critical for flower bud formation, so avoid irrigating the planting area during this dormant phase.

Ideal Temperature

Hardiness Zone Compatibility

Cut nerine stems for spectacular autumn arrangements when two or three florets in the umbel have opened. The glittering, spider-like pink flowers last ten to fourteen days in a vase, making them exceptional cut flowers. Cut stems at the base and place in clean water. The flowers have a crystalline, sparkling quality in sunlight that is unique among autumn-blooming bulbs. A single stem in a bud vase makes a striking display.

Storage & Preservation

Nerine bulbs are best left undisturbed in the ground where they naturalize and flower best when crowded. In zones colder than 7, lift bulbs after foliage dies back and store in barely damp peat in a cool, frost-free location. Alternatively, grow in deep containers that can be moved to a frost-free greenhouse for winter. Cut flowers can be dried by hanging upside down, retaining some of their form though losing the characteristic sparkle.

Troubleshooting Common Problems

The most common cause of non-flowering is insufficient summer heat reaching the bulbs. Plant as close to a warm wall as possible with the bulb necks exposed above the soil surface. Planting too deeply also inhibits flowering. Dividing too frequently disrupts the congested conditions nerines need to bloom well. In wet winter climates, crown rot is a risk and excellent drainage is essential.

Growing Tips

1. Plant bulbs against a south-facing wall or fence to maximise sun exposure and radiated warmth, which is critical for reliable flowering in cooler climates.
2. Ensure exceptionally sharp drainage by adding generous amounts of horticultural grit or coarse sand to the planting hole, particularly in clay soils where waterlogging causes bulb rot.
3. Resist the temptation to divide clumps too frequently; nerines flower most prolifically when slightly congested, and disturbed bulbs may sulk for one to two years before flowering again.
4. Water actively during the spring foliage growth period and again when flower spikes emerge in autumn, but keep bulbs completely dry during their summer dormancy rest phase.
5. Apply a high-potash liquid feed such as tomato fertiliser every two to three weeks during foliage growth to promote strong flower bud formation within the bulb.
6. Mulch over the planting area with dry straw, bark chips, or horticultural fleece in regions where winter temperatures regularly drop below minus five degrees Celsius.
7. When growing nerines in containers, use a free-draining mix of two parts loam-based compost to one part grit, and avoid repotting until bulbs are visibly pushing against the pot walls.
8. Cut flower stems for indoor arrangements when the first two or three florets on the umbel have opened; the remaining buds will continue to open in the vase over the following week.
9. Remove spent flower stems after blooming but never cut back green foliage, as the leaves are essential for photosynthesis and replenishing the bulb's energy reserves for next year's flowers.
10. In very cold regions where ground planting is not feasible, grow nerines successfully in terracotta pots that can be moved to a frost-free greenhouse or garage over winter.