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AMAZING Alstroemerias

July 28, 2008
Martha Proctor

If you are looking for a perennial that flowers profusely, requires minimal care and provides superb cut flowers, check out Alstroemerias! As exotic as orchids but far easier to grow, Alstroemeria, commonly called Peruvian Lily or Lily of the Incas, bears delicately marked, almost orchid-like flowers. The genus of approximately 50 species of flowering plants is native to South America. Many of the species originated in one of two distinct centers of diversity, central Chile (winter-growing Alstroemerias) and eastern Brazil (summer growing). The most popular and distinctive hybrids commonly grown today resulted from crosses between these two species. Ongoing research devoted to creating more widely adaptable plants has resulted in Alstroemerias that are essentially evergreen and flower most of the year. All are long-lived except a diminutive annual, Alstroemeria (Taltalia) graminea, which is found in the Atacama Desert in Chile.

The genus was named by Carolus Linnaeus (1707-1778) to honor his close friend, Claus von Alstroemer, a Swedish baron, who collected seeds from the plant on a trip to South America in 1753. The plant was first described by the French botanist Louis Feuillée (1660-1732).
For many years, only the tall deciduous type of Alstroemeria, which produces clusters of flowers for six weeks on two to five foot stems, was available to gardeners. Many gardeners hesitated to plant these otherwise gorgeous plants because of their tendency to become invasive. Alstroemerias are rhizome-like, tuberous perennials which can spread to form clumps twelve to twenty-four inches across.
Many hybrids and about 190 cultivars have been developed with distinctive flecks, dark stripes and colors ranging from white, golden yellow, orange to apricot, pink, red, purple and lavender. In August 2006, after decades of research by Könst Alstroemeria BV in the Netherlands, Princess Lilies, the dwarf Alstroemeria, appeared on the market. This hybrid is compact, slightly taller than one foot and approximately twenty inches wide. It is tough, drought tolerant, ideal for containers and gardens and yet produces up to thirty buds on one stem. These wonderful dwarf plants will flower continuously from spring to late autumn provided their few needs are met. An interesting note and a tip to identifying this plant is that the leaves twist at the base so that the upper and lower surfaces are reversed and internally the anatomy has adapted to this reversed position.
Plant the tubers as soon as you obtain them eight inches deep in full sun to partial shade preferably in late summer or early autumn. Transplants can be planted directly into the ground after the risk of night frost has ended. Plants prefer loose, fertile, well-drained soil but will tolerate a variety of soils. If your soil is mostly clay, it is advisable to dig in plenty of compost and grit to improve drainage. The roots are delicate and brittle so handle them gently, spreading them out in soft rich soil just below the surface. Add a balanced granular fertilizer to the soil before planting. Because dwarf Alstroemerias produce copious flowers, these plants perform best with adequate nourishment and water during growth and bloom. Provide sufficient water for the first three weeks of bedding; avoid allowing the soil to become waterlogged or excessively dry. Hand broadcast an annual side dressing of compost or aged manure in early spring.
The plants may take a year to become established and productive, but once they are settled in, flowering is profuse. During the first two autumns after planting, cut back the dead stems and mulch with compost, just to give the roots extra protection for the winter. Container grown plants become established more quickly but perform better if they receive extra fertilizer as a side or top dressing. After flowering, plants become dormant and no additional water is necessary. Be aware that inasmuch as Alstroemeria is a member of the Amaryllidaceae, botanical families from which many pharmaceutical products are derived, some individuals develop allergic dermatitis from the species.
In a well watered garden, snails, slugs and other pests find Alstroemerias quite a delicious treat. In a dry garden, these pests present less of a problem, but care should still be taken to protect the tender shoots of young plants.
Alstroemerias are ideal border plants, feature plants in containers, and cut flowers. For the twenty years prior to 2006, dwarf Alstroemerias were exclusively available to the cut flower trade. With the introduction of dwarf Alstromerias to the market, gardeners welcomed the opportunity to provide a welcome splash of color in their gardens while concomitantly cultivating these excellent cut flowers. In fact, the more flowers you pick, by simply pulling the stem out of the ground, the more flowers they produce. I have several stands of Alstroemerias in my garden—how can you go wrong with their lengthy flowering period, beautiful color range, and basically trouble-free growing habit?

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