Loosestrife Care Must-Knows
For best results, plant loosestrife in well-drained, consistently moist soil and full sun. The former, if nutrient-rich, will fuel the perennial’s rapid growth and extended bloom times. The latter will lead to the best foliage colors and prevent plants from flopping. For varieties with variegated or gold foliage, full sun may bleach out some of the leaves, especially in extreme southern exposures. If that’s your worry, plant loosestrife where it will be sheltered from the sun in the afternoon. The plant will still perform beautifully. Most types of loosestrife spread aggressively through underground rhizomes and have an ability to root anywhere a node touches the ground. Regular thinning keeps large stands of this plant under control; thankfully, shallow roots make the plant easy to pull out if it gets out of bounds. You can also plant loosestrife and surround it with a weed barrier or bamboo barrier to restrict its running habit. Or, cultivate this plant in a container to contain its rampant growth. Purple loosestrife, a wetland plant with showy spikes of purple flowers, is so invasive that the sale of this plant is illegal. (It belongs to the Lythraceae family, however, and should not be confused with other plants bearing the name “loosestrife.”) It spreads primarily by seeds, but a mature plant’s extensive roots can send out up to 50 shoots that create a dense woody mass. New plants can also be produced by stem fragments and pieces of roots.
More Varieties of Loosestrife
‘Alexander’ Loosestrife
A stunning variegated selection with cream-edged leaves, this plant displays tall stalks of golden-yellow, star-shaped flowers that last almost the entire growing season. Zones 4-8
Circle Flower
Lysimachia punctata, or whorled loosestrife, has whorls of 1-inch yellow flowers along the upper part of leafy 3-foot stems. The dark 3-inch leaves, sometimes variegated with white, are also arranged in whorls. In the damp areas that circle flower prefers, it may become invasive. Zones 4-8
Golden Creeping Jenny
This variety is a fast-growing groundcover for shade or partial shade. It bears round chartreuse foliage and grows 2 inches tall. It can spread indefinitely. Zones 4-8
Gooseneck Loosestrife
Lysimachia clethroides rises to 3 feet tall with stems topped with curved spikes of small white flowers. It is sometimes used as a cut flower. It is very aggressive and can become a nuisance. Zones 4-9
Purple-Leafed Loosestrife
This cultivar emerges in spring with exciting deep purple foliage that holds its color all season. Clusters of bright yellow 1-inch flowers nod atop 2- to 3-foot stems. Beware of aggressive spreading.
Loosestrife Companion Plants
Helenium
Long-blooming helenium lights up the late-season garden with showy daisy flowers in brilliant yellows, browns, and mahogany, centered with prominent yellow or brown discs. Many of the best cultivars are hybrids. All are excellent for cutting. Deadhead to extend bloom time, and divide the clumps every couple of years to ensure vigor.
Calla
Funnel-shaped white callas represent a simple cool elegance in the garden, but the colored callas add a new dimension to the plant. Now available in a rainbow of hues including lavender, purple, orange, yellow, and peach, these South African natives perk up container gardens and borders. The plants go dormant in colder winter areas of their hardiness range and do not emerge until temperatures warm up in late spring. Outside of their hardiness range, store the rhizomes in a frost-free place for winter.
Daylily
Daylilies are so easy to grow you’ll often find them growing in ditches and fields, escapees from gardens. And yet they look so delicate, producing glorious trumpet-shaped blooms in myriad colors. In fact, there are some 50,000 named hybrid cultivars in a range of flower sizes (the minis are very popular), forms, and plant heights. Some are fragrant. The flowers are borne on leafless stems. Although each bloom lasts but a single day, superior cultivars carry numerous buds on each scape so bloom time is long, especially if you deadhead daily. The strappy foliage may be evergreen or deciduous.
Veronica
Easy and undemanding, veronicas catch the eye in sunny gardens over many months. Some have mats with loose clusters of saucer-shaped flowers, while others group their star or tubular flowers into erect tight spikes. A few veronicas bring elusive blue to the garden, but more often the flowers are purplish or violet blue, rosy pink, or white. Provide full sun and average well-drained soil. Regular deadheading extends bloom time.
