A vigorous amphibious knotweed.
Common name : Loogroot
Scientific name : Persicaria amphibia
Family : Poaceae
Category : Perennials
Type of plant : Perennial
Sun loving
Sun loving
Extra water
Extra water
Persicaria amphibia - the longroot - is a species of flowering plant in the knotweed family, native to much of North America, Asia, Europe, and parts of Africa and iknown elsewhere as an introduced species and sometimes a noxious weed. Persicaria amphibia produces a thick stem from its rhizome that may creep, float, or grow erect, rooting at stem nodes that come in contact with moist substrate. Stems are ribbed and may reach 3 meters (10 ft) long, and leaves are lance-shaped and may be over 30 centimeters (1 ft) in length. The inflorescence is a dense terminal cluster of many five-lobed pink flowers.

Sowing & planting



Water needs
Granulométrie plants.granulometry_3
Frost-resistance High
Zone USDA 7a
Height 30 - 45
pH 5 - 7

Plant my longroot

Plant preferably between September and the end of November or between March and the end of April, when the winter reserves are formed and the temperatures are not too low. Bury the roots a few centimeters so that the foliage is flush. Fill and pack well around the plant so as not to leave a pocket of air. Water copiously just after planting. If you are planting in a pot, use one whose volume corresponds to that of the plant, otherwise you will have to water it too often. You can use gravel at the bottom under mixture of soil, compost or compost for better drainage.

Water my longroot

Water regularly in the first weeks. Try to avoid watering on sunny afternoons to minimize the amount of moisture lost to evaporation. If your plant is in a pot, check the top soil in the pot either by looking at it or touching it with your finger. In any case, if it hasn’t rained in a month, water !

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