These large bulbs belong to the Amaryllidaceae family, which contains many bulbs which do very well in the Sydney climate, including Amaryllis, Nerine, Clivia, Leucojum, Hymenocallis, Scadoxus and Haemanthus. They are found in Central and South America and there are about 80 species as well as any number of hybrid forms in colours of reds, orange, pinks and white, including double forms. The bold funnel-shaped flowers are born atop of a stout stem (ht 60 cm) from late winter to spring. My bulbs (pictured) was grown from seeds given to me by a friend, and took about three years ago to flower. I thought the seeds were from a pink-flowered specimen, but as with much seed-raising of cultivars, the offspring can vary in colour. These bulbs need well-drained reasonable soil in sun, and the top third of the bulb should be left exposed. They can be grown in pots, preferably a smaller one where the bulbs will fit rather tightly. Pots can be brought inside when the bulbs are blooming, for a week or so. The flowers can be cut for vases.
Apply some liquid fertiliser whilst the foliage is dying down - thereafter, the bulbs should be kept dry whilst dormant. Protect the buds and flowers from snails. The scary black and yellow striped amaryllis caterpillars (also known as the lily borers) may attack in spring and can cause a lot of damage to the whole plant in a very short time; they should be dealt with promptly, using a product such as Success, Dipel or a pyrethrum spray. They can also be picked off by hand and squashed!