Persicaria alpina

Alpine knotweed, Persicaria alpina, is a substantial herbaceous perennial with pointed green leaves topped by fluffy flower plumes from midsummer and into autumn. Don't be put off by its common name; Persicaria alpina is easy to grow, but not thuggish or invasive, although it does resemble Japanese knotweed.

Persicaria alpina enjoys growing in moist soil, so it's a great choice for growing near ponds, allowing the water to catch its reflection.

For best results, grow Persicaria alpina in full sun or partial shade in moist, well-drained soil, sheltered from strong winds. Cut back the foliage to the base of the plant after it has been hit by the first frosts.