Alstroemeria, known as the Peruvian or Inca lily, is a South American native plant that produces orchid-like flowers in colours from light yellow or lavender to the darkest crimson. They are hardy throughout the British Isles.
Alstroemeria is planted in autumn or spring where it is reliably hardy. The University of North Carolina extension recommends spring planting, but Western Australia's Department of Agriculture and Food cites autumn as the common time to plant bulbs.
Members of the lilium family of plants require a cool dormant period before growth begins, so autumn planting works well in areas where winters are cool but the ground does not freeze. In areas where the ground stays warm during winter and in Central Scotland or the Northern Isles, where plants are hardy only with mulch, spring planting fits dormancy patterns.
Northern gardeners may plant bulbs indoors in containers during late winter for spring and summer bloom. Bring pots indoors for winter or dig up the tubers and store them in a cool, dry place.
Many Peruvian lilies, particularly the common Alstroemeria aurea, are vigorous growers and propagate rapidly. In locations that replicate their native elevations and climate environments, they can become invasive.