Knotweed
Polygonum avicularefam. Polygonaceae
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Pl. 1F14 — Polygonum aviculare
Polygonum avicularePolygonum avicularePolygonum avicularePolygonum avicularePolygonum avicularePolygonum avicularePolygonum avicularePolygonum avicularePolygonum avicularePolygonum avicularePolygonum avicularePolygonum avicularePolygonum avicularePolygonum aviculare
IOverview
Overview
Knotweed (Polygonum aviculare) is a widespread annual forb or herb found across a broad range including Afghanistan, Alabama, Alaska, and many other regions from Europe to Asia and North America. Known for its edible leaves and seeds, it also has documented medicinal uses. This plant thrives in moist, light to heavy soil with a pH of 5.5–6.5, making it adaptable to various environments. Its distinctive feature is its ability to grow up to 0.3 meters tall, contributing to its presence in diverse habitats from coastal areas to inland regions. Knotweed's hardiness spans zones 4-8, allowing for cultivation across a wide range of climates.
Quick answers
What is Knotweed?
Knotweed (Polygonum aviculare) is a widespread annual forb or herb found across a broad range including Afghanistan, Alabama, Alaska, and many other regions from Europe to Asia and North America. Known for its edible leaves and seeds, it also has documented medicinal uses.
IV·bMixology suggestions
2 drafts
Mixology suggestions
2 draftsEditorial drafts. These pairings are AI-suggested from traditional herbal lore. Always verify with a qualified herbalist before brewing.
Knotweed and Lady's Bedstraw
skintincture
Traditionally used for skin conditions.
Knotweed and Watercress
digestiontea
Historically used to aid digestion.
Growingconditions · propagation · uses
VCultivation
Cultivation
Knotweed thrives in light to medium soils with a pH between 5.5 and 6.5, preferring moist conditions but tolerating a variety of soil types including sandy, loamy, and clay. It is hardy in temperate regions within zones 4-8 and can grow up to 0.3 meters tall. Knotweed requires full sun to partial shade and should be watered regularly to maintain its moisture needs. Propagation can occur through seeds or by dividing the roots. Harvest edible parts, such as leaves and seeds, throughout the growing season.
Light
7/10
Water
Moist
Soil
Light (sandy), Medium, Heavy (clay)
Hardiness
4-8
Life cycle
Annual
Habit
Forb/herb
Mature size
0.3 m tall
Soil pH
5.5–6.5
For first-time growers
How to grow Knotweed for the first time
7steps
Knotweed is a forgiving plant for beginners, making it an excellent choice for your first gardening project.
- 1
What you'll need
Seeds or young plants, a small trowel, and a watering can.
- 2
Best time to plant
Plant in early spring after the last frost or in late summer for fall germination.
- 3
Soil and container prep
Ensure soil is well-draining with a pH between 5.5 and 6.5, and prepare containers at least 30 cm deep.
- 4
Sowing or transplanting
Direct sow seeds in the ground or start them indoors about 4 weeks before planting outside. Transplant young plants after danger of frost passes.
- 5
First two weeks
Keep soil consistently moist and provide partial shade to help seedlings establish.
- 6
Ongoing care
Water regularly, especially during dry spells, and mulch around the base for moisture retention. Prune back any dead or overgrown foliage as needed.
- 7
Harvest or pruning
Prune plants in late winter to maintain shape and encourage new growth.
VIEdible & utility
Edible & utility
Edible parts:LeavesSeed
Edible uses: Tea
Other uses:Dye
Contextrange · companions · related
VIIDistribution
30 native · 0 introduced
Distribution
30 native · 0 introducedDistribution across4 continents· 30 native
Europe10 regions
native (10)AlbaniaAustriaBelarusBelgiumBulgariaCyprusFrancePortugalRussiaSpain
Asia2 regions
native (2)AfghanistanChina
Americas1 region
native (1)United States
Africa1 region
native (1)Algeria
Broader regions
native:Alabama, Alberta, Altay, Amur, Arizona, Arkansas, Baltic States, British Columbia, Buryatiya, California, Chita, Colorado, Connecticut, Czechoslovakia
IXSpecimen gallery
1 image
Specimen gallery
1 imageXSee also
8 related
See also
8 relatedPlants you might compare or use together — scored by shared family (Polygonaceae), common use cases, and growing requirements.
same family · Polygonaceae
Botanical relatives — often share phytochemistry + growing needs.
XI
Explore further
Companion planting
Compare with similar plants
Growing zone
XII
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