Kingdom:   Plantae
(Unranked):        Angiosperms
(Unranked):        Monocots
Order:       Liliales
Family:      Alstroemeriaceae
Genus:      Alstroemeria
Species: Alstroemeria spp.
Common names: Peruvian lily, lily of the Incas.

Many hybrids and about 190 cultivars of the genus Alstroemeria have been developed, with different markings and colours, ranging from white, golden yellow, and orange, to apricot, pink, red, purple, and lavender. The most popular and showy hybrids that are commonly grown today result from crosses between species from Chile (winter-growing) with species from Brazil (summer-growing).
The plants are distinctive vegetatively, with a rootstock consisting of a slender rhizome or group of rhizomes (the "crown"). Storage roots consist of sausage-like water storing structures "suspended" from the rhizome by major roots. In this way, the root system resembles that of dahlias. Above-ground shoots may be very short in some alpine Andean species (a few inches tall) or up to about 5 feet (1.5 m) tall in other species. Each year (more often in some hybrids) up to 80 new shoots are produced from the rootstock and each terminates in an umbel of a few up to 10 or so flowers.
Perhaps the most fascinating- and telltale morphological trait of Alstroemeria and its relatives is the fact that the leaves are resupinate, that is, they twist from the base so that what appears to be the upper leaf surface is, in fact, the lower leaf surface. This very unusual botanical feature is easily observed in the leaves on cut flowers from the florist.
The flowers of Alstroemeria are generally showy. All six tepals (tepal denotes either petal or sepal when both are similar, as in lilies, amaryllis, etc.) are roughly similar. In some species, two tepals are enlarged and vividly coloured and act as "flags" for pollination. The ovary is inferior and the seeds are hard and rounded.
This species can become invasive.Alstroemeria species Peruvian lily -008.JPG

Alstroemeria species Peruvian lily -002.JPG

The leaves twist from the base so that what appears to be the upper leaf surface is, in fact, the lower leaf surface.
Alstroemeria aurea Peruvian lily-002.JPG

Thanks to Wikipedia for text and information: