Common Name: loosestrife
Type: Herbaceous perennial
Family: Primulaceae
Native Range: Central Europe, Asia Minor
Zone: 4 to 8
Height: 2.00 to 3.00 feet
Spread: 1.00 to 1.50 feet
Bloom Time: May to September
Bloom Description: Bright yellow
Sun: Full sun to part shade
Water: Medium to wet
Maintenance: Medium
Suggested Use: Naturalize
Flower: Showy
Culture
Easily grown in moist, humusy, well-drained soils in full sun to part shade. Plants prefer some part afternoon shade in the St. Louis area. Plants will spread by rhizomes and are self-seeding in optimum growing conditions to form large colonies. Plants tend to be less aggressive if grown in lean, somewhat dry soils, however best performance is in moist fertile soils.
Noteworthy Characteristics
Lysimachia punctata, commonly called loosestrife, is native to central/southern Europe and Turkey, but has over time escaped gardens throughout many parts of the northern U.S., particularly in the northeastern states, where it has naturalized in waste places, ditches and along roadsides. It is a rhizomatous perennial that grows to 3’ (infrequently to 4’) tall on stiff upright stems clad with pubescent, ovate to lance-shaped, medium green leaves (to 3” long) in whorls of 3 or 4 (occasionally opposite). Cup-shaped, five-petalled, bright yellow flowers (to 1” across) in axillary whorls bloom from May to September. Additional common names for this plant include yellow loosestrife, garden loosestrife or whorled loosestrife. Notwithstanding the common names, Lysimachia is a member of the primrose family and not the loosestrife family (Lythrum). Lysimachia is not as aggressive a spreader as the infamous purple loosestrife, Lythrum salicaria.
Genus name honors King Lysimachus (661-281 B.C.), Macedonian King of Thrace and is derived from lysimacheios which was the ancient Greek name of a plant in this grouping.
Specific epithet means spotted.
Problems
No serious insect or disease problems. Lysimachia is susceptible to rust and leaf spots. Plants should be closely monitored to avoid unwanted spread.
Uses
Best in areas separated from other valued perennials where it can be allowed to naturalize into large colonies. Also may be grown in cottage gardens, wild gardens, remote parts of borders, pool peripheries or along streams.