Surprising bulbs

Wednesday, 11 March 2009

Late summer and early autumn can hold some delightful surprises in our Sydney climate. There is a group of bulbs, all from the Amaryllidaceae family, which have the novel characteristic of sending up their flowering spikes almost overnight at this time of year, seeming to come from nowhere, as they usually have no leaves when they bloom. Their sudden appearance and exquisite forms add fresh interest at a time when other plants are starting to going into a decline. They can be rather unpredictable, as in some seasons they don't seem to get round to flowering; however, this seems to just add to their mystique.

They prefer to be left undisturbed to form clumps. Generally, they are dormant over summer until they bloom, so should be kept fairly dry at that time, but they enjoy a little moisture during their winter-spring growing period. Most lose their leaves in the warmer weather, and these do not appear until after flowering. They benefit from some bulb fertiliser when the foliage is in active growth.

The belladonna lily or 'naked lady' (Amaryllis belladonna) is one of the best known and easiest to grow of these bulbs, with stout stems up to 75cm tall topped with dramatic clusters of large trumpet flowers of white, various shades of pink, or pink with a white throat, appearing around February. The large strap-like leaves appear after the flowers then die off rather messily in late spring to early summer. This bulb is very tolerant of neglect and can often be seen flowering in abandoned country gardens. It should be planted in well-drained soil in a sunny spot, and with the bulb neck exposed above soil level.

Appearing around March are the narrow ruffled petals and long whiskery stamens of red or yellow spider lily bulbs (Lycoris radiata and Lycoris aurea, ht 40cm). They are the most unpredictable of bulbs, seeming to be quite affected by seasonal factors, but when they do appear, they are quite spectacular. They seem to flower best after a hot, dry summer; however, they are actually woodland bulbs and are best grown in semi-shade, with their necks buried.

Storm lilies (Zephyranthes species, ht 15-25cm) have grassy foliage and flowers rather like a crocus, and are easily grown in Sydney. Zephyranthes candida has papery white or pink flowers and thin evergreen foliage, whilst Zephyranthes grandiflora has pretty pink blooms, is dormant in winter, and usually begins to flower earlier in the summer than the white species. Both seem to come into bloom after rain has fallen, hence their common name, and several flushes of flowers can be expected if there a few periods of rain in late summer and autumn. There are also rare yellow forms, in both bright and pastel shades (such as Zephyranthes primulina). They form thick clumps and can survive in quite dry positions, such as at the base of a hedge. They are best grown in sun.

A related plant is Habranthus robustus, with similarly shaped flowers and leaves. The flowers are rose-pink, fading to white. Both Zephyranthes and Habranthus make good pot plants, as does the Scarborough lily (Cyrtanthus elatus, syn. Vallota speciosa, ht 30cm), which has bold scarlet-orange clusters of funnel-shaped flowers in early autumn. It is tolerant of most conditions and easy to grow. There are many Hippeastrum out in bloom in gardens around here at the moment, though their main flowering period is usually spring.

These bulbs all provide an element of dynamism in the garden, an extra note of interest which can intrigue and delight the gardener. Some are available in nurseries or mail order catalogues in summer, when the bulbs are dormant; the rest can be found in those precious plant arks: the gardens of inveterate collectors, who may be able to be persuaded to part with a few if begged nicely ...