Seashore Mallow (Kosteletzkya virginica)

Where to plant: at the high-water mark; can be in shallow water temporarily. Brackish to nearly fresh water. Also grows well in fresh water environments, but has trouble competing against most fresh water species.
Type: perennial herb wildflower
Height x spread: 3-5 ft x up to 4 ft spread at maturity, which it reaches in about 5 years. Once it reaches this height, it lives about another 5 years. But its seeds produce new plants.
Blooms: May into October
Bloom: pink
Sun: full sun (6 or more hours of direct sunlight a day)
Water: medium to wet 
Maintenance: low
Attracts: butterflies, hummingbirds, pollinators
Dear tolerance: minimal

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https://www.growingwildnursery.com/blogs/news/seashore-mallow

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