This section is from the book "Commercial Gardening Vol2", by John Weathers (the Editor). Also available from Amazon: Commercial Gardening, A Practical & Scientific Treatise For Market Gardeners.
Large bulbous-rooted plants from South Africa, almost hardy, and best grown in south borders at the base of a warm wall in rich well-drained soil. They have large bulbs, strap-shaped rosettes of leaves mottled beneath, and fleshy spikes of starry flowers. They are best increased by offsets. The following kinds are known: bicolor, greenish yellow; guttata, 3 ft., greenish white and purple; punctata, 3-4 ft., similar; and regia, 2-3 ft, white - all blooming in late summer and autumn.