CHAPTER 1
BULBS FOR THE AUTUMN
NOTE
Summer-growing bulbs like eucomis, some of which flower in the early autumn, are listed in the summer section.
Say ‘bulbs’ to any gardener and their mind jumps to drifts of daffodils under cherry trees, but autumn, normally regarded as the season of decay, is the most important time in the life of a bulb. As the first rains fall in the Mediterranean areas or the leaves fall in temperate woodlands allowing more rainfall to reach the soil, so moisture breaks the drought-induced summer dormancy and the bulbs begin to grow. For most it is just the production of the roots that are so essential for future growth but for a few it is their flowering season as well. Surrounded by fallen leaves, they are a sight as welcome as they are unexpected on a sunny autumn day. Most autumn-flowering bulbs are planted in late summer or early autumn, just before they flower.
The showiest of the autumn-flowering bulbs are those from southern Africa such as the autumn lily Nerine bowdenii or Amaryllis belladonna, which rely on a dry summer to ripen their bulbs. These are planted in early spring as they come into leaf, although pot-grown ones can be planted at any time.
Acis
(Leucojum)
Long included in Leucojum, these are now a genus in their own right. There are a number of very similar species but only one is really suitable for the open garden. It is often the first sign of autumn, frequently starting to flower in late summer.
A. autumnalis
As summer draws to a close, these tiny bulbs erupt into flower, almost overnight pushing up their slender stems, each topped with one or two tiny nodding purple-tipped white bells. These are followed by thin, grassy leaves. Northern Spain is their home, so they prefer a dry summer when they are dormant, and grow well on a sunny rock garden or around the base of a small tree. They are clump-forming and give their best display when well established. Height: 20cm.
Amaryllis
This single-species genus from South Africa is often confused with the non-hardy South American relative, the Christmas-flowering Hippeastrum. Amaryllis produce a cluster of six or more trumpet flowers on stout stems which are followed much later by the leaves. They can produce flowers at any time from late summer to autumn depending upon the weather in the preceding summer. They are reputed to be hardy to -5˚C although we have grown them outside where the temperature has dropped much lower. More important is a warm, dry summer to encourage flowering. Bulbs that are overshadowed by neighbouring plants or receive too much water during the summer will fail to ripen and flower. Our bulbs grow freely in an open bed in the nursery but produce only sporadic flowers. Another clump injudiciously planted against a wall became smothered by its neighbours. It grew very well but never flowered until the offending vegetation was removed to allow the sunlight to fall directly upon the bulbs. The ideal position for all these autumn-flowering South African bulbs is against a dry, sunny wall where they can be left undisturbed to form large clumps. Mature, congested clumps flower best. They seem to do best in relatively frost-free locations such as near the sea and especially in the Channel Islands, where virtually every front garden is adorned by dramatic displays in October. The flowers are followed by long strap-shaped basal leaves that grow during the winter, gradually fading as the summer progresses. They make easy and attractive pot subjects for a cold glasshouse or conservatory.
Cultivation
The bulbs are planted in early spring just below the surface of the soil in a very sunny position in well-drained soil. Narcissus fly can be a problem in some gardens and slugs may damage the flowers.
Propagation
Congested clumps can be carefully split in the spring. Small offsets are best grown on under glass for a couple of years. Seed should be sown under glass as soon as it is ripe.
A. belladonna
This produces an umbel of up to six pale pink, lightly scented flowers in the autumn, followed by long strap-shaped leaves. Ther...