Kosteletzkya pentacarpos, the seashore mallow, sweat weed, Virginia saltmarsh mallow, or salt marsh mallow, is an herb found in marshesalong the eastern seashore of the United States. This flowering plant is in family Malvaceae of the order Malvales. The pink-flowered seashore mallow is both a perennial and a halophyte, or salt-tolerant plant, that grows in areas where other plants cannot. The plant can grow to above 1 metre in height, the leaves are 6–14 cm long, cordate to lanceolate with toothed margins. The stems and leaves are hairy.Flowers are 5–8 cm across, with 5 petals surrounding a tube consisting of the fused stamens and style. It blooms from July to October with pale to deep pink flowers.It is occasionally planted in gardens.