Purple Loosestrife Lythrum salicaria
- Phonetic Spelling
- LITH-rum sal-ih-KAIR-ee-ah
- This plant is an invasive species in North Carolina
This plant is problematic and alternatives should be considered. Please see the suggestions in the left-hand column.
Purple loosestrife is a perennial weed in the Lythraceae (loosestrife) family native to Africa and Eurasia. Commonily found growing in waste areas, roadsides, and sites with wet soil conditions. The plant will grow from 2 to 6 feet tall
Very tolerant of wet sites and full sun. The roots are thick and send out many runners forming an extensive underground network from which new plants can sprout. The showy purple pink flowers appear from mid to late summer and are followed by capsules filled with thousands of tiny seeds that are easily dispersed by wind, water, and animals.
It is currently against the law in North Carolina and many other states to sell Purple loosestrife, because it escapes from cultivation and becomes a prolific weed in wetland areas, choking out native vegetation essential for waterfowl. Named cultivars once thought to be non-invasive are now known to cross and develop strains that spread rapidly in the landscape. Purple loosestrife is not recommended nor is it legal for cultivation (is it a noxious weed in North Carolina).
Insects, Diseases, and Other Plant Problems: Consider growing native plants. See the list on the sidebar. Listed as invasive by the NC Invasive Plant Council. This species is on the NC noxious weed list.
- See this plant in the following landscape:
- Cultivars / Varieties:
- Cultivars / Varieties:
- Life Cycle:
- Recommended Propagation Strategy:
- Stem Cutting
- Country Or Region Of Origin:
- Europe, Africa and Asia-Temperate
- Naturalized and invasive in the USA
- Height: 2 ft. 0 in. - 6 ft. 0 in.
- Width: 2 ft. 0 in. - 4 ft. 0 in.
Whole Plant Traits:
- Plant Type:
- Herbaceous Perennial
- Growth Rate:
- Full sun (6 or more hours of direct sunlight a day)
- Soil Drainage:
- Good Drainage
- Occasionally Wet
- USDA Plant Hardiness Zone:
- 3a, 3b, 4a, 4b, 5a, 5b, 6a, 6b, 7a, 7b, 8a, 8b, 9a, 9b
- Fruit Color:
- Fruit Type:
- Fruit Description:
- Tan capsules that appear as early as July with many tiny seeds aid in the quick dispersion of this plant. Seeds the size of sand spread by wind, water, humans, and animals.
- Flower Color:
- Flower Inflorescence:
- Flower Bloom Time:
- Flower Description:
- Intense purplish-pink flowers with 5 to 6 petals yellow centers arranged in 1 foot tall spikes that bloom from early July to September.
- Leaf Feel:
- Leaf Arrangement:
- Leaf Shape:
- Hairs Present:
- Leaf Length:
- 3-6 inches
- Leaf Description:
- The 4 inch long leaves are stemless and lance-shaped and either opposite or whorled in an arrangement.
- Stem Color:
- Stem Is Aromatic:
- Stem Cross Section:
- Stem Form:
- Stem Description:
- 4 to 6 sided square shaped stem
- Resistance To Challenges:
- Wet Soil
- Invasive Species