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. The Brazilian species Hippeastrum papilio - sometimes called the butterfly amaryllis - has white flowers with striking burgundy markings with a touch of lime. The flowers can be picked for vases.
They can be grown outdoors in our climate, either in the ground or in pots. Pots should be on the small size so there is a snug fit. Potted bulbs can be brought inside when blooming, for a week or so. They will multiply well if planted in the ground. They should be grown in a sunny position, in well-drained soil with added organic matter. The neck of the bulb should be well exposed above soil level. While in full growth, and after flowering, they enjoy ample water, but after the foliage has died down and they are dormant (in mid summer), it is best to keep them on the dry side. Propagate from natural offsets or seed; divide when overcrowded, every two years. I have noticed that they can begin to rot off during times of heavy rain in summer if they are too congested. Unlike some bulbs, they don't mind being divided and will flower better afterwards! A weak dose of liquid fertiliser when flower stems appear, and another after flowering is over, will be beneficial.
Protect the buds and flowers from snails. The scary black and yellow striped amaryllis caterpillars (also known as the lily borers) can attack in spring, and can cause a lot of damage to the whole plant in a very short time. These 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!