×
To buy, sell or swap plants and use our full service please log in or sign up – GreenPlantSwap is completely free!
Record your plants before you lose the plant labels! Just tick the ‘Garden’ box (below) on each plant. Learn more

Polygonum polystachyum

Himalayan knotweed

Garden

Wishlist

  • Plant Placeholder

Features

  • BloomsSeptember to October
  • Height1.4m to 1.8m
  • Spread1.1m to 1.5m
  • Growth HabitMound
  • Flower ColourWhite

Description

Polygonum polystachyum (Himalayan knotweed). A fast-growing perennial herb from The Himalayas.

Characteristics

Perennial, Deciduous or Evergreen, Fragrant

Other common names

Knotweed

Origin

E. Asia - Himalayas

Interest and use

Can be used for ground cover, edging or rock gardens. Suitable for coastal conditions. Attracts butterflies.

Search or browse our Glossary of 3,000+ botanical and plant-related terms


Have something to say about this plant?
Click to write a post, ask a question or share a tip.


  • Plant Placeholder

Needs

  • LightPart shade
  • HardinessFully hardy (min -23°C)
  • SoilHeavy, Light, Medium
  • Soil pH6.0 to 7.0
  • WaterSemi-moist

Cultivation

They are fully to half hardy and will tolerate sun or shade in well drained soil.

Propagation

Seed or division in autumn or spring, climbers only by semi-ripe cuttings in summer.

Search or browse our Glossary of 3,000+ botanical and plant-related terms


Have something to say about this plant?
Click to write a post, ask a question or share a tip.


Have something to say about this plant?
Click to write a post, ask a question or share a tip.


Sorry. No results found. Please adjust your search…

    To view Polygonum plants offered near you, enter your postcode or log in.

    Get started & find out why

    Posts of the WeekPosts & Events

    Open your garden for Thrive
    • Rhubarb
    • Watering
    • Digging
    • Sunflower
    • Potting
    • Grass

    “It’s not just gardening,
    it makes us healthier and happier”

    Production v5.2.0 (1129a0a)