Polygonum equisetiforme is a perennial knotweed that can form mats, clumps or grow upright to about 1.0 m. It has deciduous, simple leaves that range from lance-shaped to heart-shaped and are often marked or take on autumn tints. Flowering occurs July to September. It suits a wide range of sites, including heavy clay and damp ground.

Knotweed (Polygonum equisetiforme) is a perennial from Portugal that reaches about 1.0 m and flowers July to September.

The knotweeds are vigorous, long-flowering plants carrying dense narrow spikes or loose sprays of tiny flowers, usually in pink, crimson or greenish white, above simple lance-shaped or heart-shaped foliage that frequently colours well in autumn. Habit varies enormously, from low creeping mats that make dense weed-suppressing cover to tall, architectural clump-formers. Several are extremely vigorous, and the genus has been extensively reclassified, with many garden plants now placed in Persicaria.

Polygonum equisetiforme

Knotweed | Polygonum equisetiforme

Polygonum hookeri is a spreading branched cultivar of the Polygonum genus, known for its deciduous foliage. It thrives in a variety of light conditions, from full sun to full shade, and adapts well to different soil types including chalk, clay, loam, and sand, provided the soil is moist but well-drained. Hardy to UK zone H7, it suits both exposed and sheltered locations. This cultivar is ideal for flower borders, beds, underplanting of roses and shrubs, and informal garden settings, offering interest in spring and summer. It can be propagated by division in spring or by seed sown in containers in a cold frame.

Polygonum hookeri thrives in full sun to shade, is RHS H7 hardy, perfect for borders, underplanting, and cut flowers from spring to summer.

Polygonum hookeri

Polygonum milletii is a perennial member of the buckwheat family (Polygonaceae) that can grow as a mat-forming ground cover, clump-forming plant or as a taller upright perennial. The leaves are deciduous, simple and range from lance-shaped to heart-shaped, often showing markings or autumn tint. It flowers from July to September. It tolerates a wide range of soils, including heavy clay, and prefers moist conditions.

Polygonum milletii is a perennial knotweed that flowers July to September and suits moist soil in full sun to partial shade.

Polygonum milletii

Knotweed | Polygonum milletii

Polygonum paniculatum is a perennial member of the buckwheat family (Polygonaceae) with a notably variable habit: it may be mat-forming, clump-forming or grow tall and upright. Leaves are deciduous, simple and range from lance-shaped to heart-shaped, often marked or taking on autumn tint. It prefers full sun to partial shade and tolerates almost any soil, including heavy clay, as long as the ground remains reasonably moist. Flowers are produced from July to September.

Knotweed (Polygonum paniculatum) is a perennial that flowers from July to September and tolerates moist soil and heavy clay.

Polygonum paniculatum

Knotweed | Polygonum paniculatum

Polygonum polystachyum is a perennial in the knotweed family that can be mat-forming, clump-forming or grow tall and upright. Plants reach about 1.8 m and carry deciduous, lance- to heart-shaped leaves that are often marked or turn autumn-tinted. It flowers from July to September. It tolerates full sun to partial shade and a wide range of soils, including heavy clay.

Himalayan knotweed (Polygonum polystachyum) is a Himalayan perennial to about 1.8 m that prefers moist soil in full sun to partial shade.

https://en.wikipedia.org/wiki/Koenigia_polystachya

Polygonum polystachyum

Himalayan knotweed, Cultivated knotweed | Polygonum polystachyum

Polygonum regelianum is a perennial knotweed that shows a notably variable habit, from mat-forming and clump-forming to taller, upright growth. Its deciduous leaves are simple, lance-shaped to heart-shaped and are often marked or take on autumn tints before falling. Flowering occurs July to September. It tolerates a wide range of soils, including heavy clay, and prefers reliably moist conditions over drought.

Knotweed (Polygonum regelianum) is a perennial with variable habit that flowers July to September and suits moist soils in full sun to partial shade.

Polygonum regelianum

Knotweed | Polygonum regelianum

Polygonum rude is a perennial in the knotweed family with a variable habit that can be mat-forming, clump-forming or tall and upright. The foliage is deciduous, simple and ranges from lance-shaped to heart-shaped, often marked or taking on autumn tints. It flowers from July to September. Plants tolerate almost any soil, including heavy clay, and prefer moist conditions in full sun to partial shade.

Knotweed (Polygonum rude) is a deciduous perennial that flowers July to September and thrives in moist soils, tolerating heavy clay in sun or part shade.

Polygonum rude

Knotweed | Polygonum rude

Polygonum sphaerostachyum is a perennial knotweed that may form mats, clumps or grow tall and upright. It has deciduous, simple leaves that range from lance-shaped to heart-shaped and are often marked or take on autumn tints. Flowering occurs July to September. The species tolerates a wide range of soils, including heavy clay, and prefers moist conditions.

Knotweed (Polygonum sphaerostachyum) is a perennial that flowers July to September and tolerates heavy clay and damp soils.

https://en.wikipedia.org/wiki/Bistorta_macrophylla

Polygonum sphaerostachyum

Knotweed | Polygonum sphaerostachyum

Polygonum ussuriense is a perennial knotweed that can be mat-forming, clump-forming or grow tall and upright. Its deciduous leaves are simple, lance- to heart-shaped and are often marked or take on autumn tint. Flowering in the UK occurs from July to September. It tolerates full sun to partial shade and will grow in almost any soil, including heavy clay, provided the ground stays reasonably moist.

Knotweed (Polygonum ussuriense) is a deciduous perennial from northeast Asia that flowers July to September and tolerates heavy clay and moist ground.

Polygonum ussuriense

Knotweed | Polygonum ussuriense

Rheum, commonly known as rhubarb, is a bushy cultivar of the Rheum genus, which comprises sturdy herbaceous perennials growing from rhizomes. This cultivar features deciduous foliage and thrives in fertile, moist but well-drained loam soil with an acid to neutral pH. Suitable for full sun or partial shade and various garden aspects, it is hardy to UK zone H6. Its tall stems bear large clusters of small flowers, making it an architectural addition to cottage, informal, wildlife, and flower border gardens during spring and summer.

Rhubarb (Rheum) thrives in full sun or partial shade, hardy to RHS H6, ideal for architectural and wildlife gardens with spring and summer interest.

Rheum

Rhubarb | Rheum

Rheum alexandrae is a perennial in the knotweed family (Polygonaceae) valued for ornamental use in borders and water gardens. It originates from south-west China and flowers in the UK from June to July. Planting and handling require care because all parts are harmful if eaten; wear gloves and protective equipment when working with it.

Alexander's rhubarb (Rheum alexandrae) is a perennial for partial shade and moist, acidic to neutral soils, flowering in the UK from June to July.

Rheum alexandrae

Alexander's rhubarb | Rheum alexandrae

Rheum australe is a perennial herb native to the Himalayas that can reach about 3.0 m in height. It flowers in the UK from June to July. Plant it in full sun on loamy or clay soils that remain moist but drain well. Parts are harmful if eaten, so wear gloves and protective equipment when handling.

Himalayan rhubarb (Rheum australe) is a tall perennial that flowers June to July and prefers full sun on moist, well-drained loamy or clay soil.

https://en.wikipedia.org/wiki/Rheum_australe

Rheum australe

Himalayan rhubarb | Rheum australe

It is an extraordinary species of rhubarb (genus Rheum). At 1–2 m tall, the monocarpic inflorescences of R. nobile tower above the other shrubs and low herbs in its habitat, and it is visible across valleys from several kilometres. R. nobile is often called a glasshouse plant because of its outer curtain of translucent bracts which pass visible light, creating a greenhouse effect, while blocking ultraviolet radiation. These are likely defenses against the increased UV-B exposure and extreme cold in its high altitude range. It is native to Afghanistan, East Himalaya, Myanmar, Nepal, Pakistan and other regions. In the garden it prefers full sun and partial shade and loam soil. In UK gardens it is very hardy across most of the UK (RHS H6). Suggested uses include architectural, cottage and informal garden, wildlife gardens and flower borders and beds. It tolerates acid and neutral soils, moist but well-drained conditions and south-facing, east-facing, north-facing and west-facing aspects.

Rheum nobile, commonly known as Sikkim rhubarb, is a robust perennial in the Polygonaceae family. Characterized by its substantial lobed leaves and tall stems, this species produces large clusters of small flowers, adding unique texture to any plant collection.

https://en.wikipedia.org/wiki/Rheum_nobile

Rheum nobile

Sikkim rhubarb | Rheum nobile

Rheum officinale is a perennial herb in the Polygonaceae that reaches around 2.0 m and produces prominent flowering stems in June to July. It prefers full sun on loamy or clay soils that remain moist but are well drained. Rated H6 (very hardy) it will tolerate typical UK winters across much of the country. Allow generous space for its height when siting it in a border or specimen position.

Chinese Rhubarb (Rheum officinale) is a perennial to 2.0 m that flowers in June–July and prefers full sun with moist, loamy or clay, well-drained soil.

https://en.wikipedia.org/wiki/Rheum_officinale

Rheum officinale

Chinese rhubarb | Rheum officinale

Rheum palmatum is a tall perennial herbaceous plant in the knotweed family that can reach about 3.0 m. It is native to China and Vietnam and flowers in the UK from June to July. Plant in full sun on loamy or clay soils that remain moist but are well drained. Harmful if eaten; wear gloves and other protective equipment when handling.

Chinese rhubarb (Rheum palmatum) is a tall perennial that flowers June to July and suits moist, loamy or clay soils in full sun.

https://en.wikipedia.org/wiki/Rheum_palmatum

Rheum palmatum

Chinese rhubarb | Rheum palmatum

Rheum palmatum 'Atrosanguineum' is a perennial Rheum grown as an architectural, tall-stemmed specimen reaching about 3.0 m. It flowers in June to July and is valued at the back of large borders or as a single focal plant. Originating from China and placed in the Polygonaceae family, it prefers full sun on moist, loamy or clay soils. Wear gloves and other protective equipment when handling, as the plant is harmful if eaten and can be dangerous to pets.

Rhubarb 'Atrosanguineum' is a tall Rheum perennial from China that flowers in June to July and prefers full sun with moist loamy or clay soil.

Rheum palmatum 'Atrosanguineum'

Rhubarb 'Atrosanguineum' | Rheum palmatum 'Atrosanguineum'

Rheum palmatum 'Bowles' Variety' is a perennial in the knotweed family that reaches about 3.0 m and produces tall flowering stems above large palmate leaves. It flowers in June to July, with pink blooms presented on erect panicles. Plant in full sun on loamy or clay soils that remain moist but well-drained and expect it to tolerate UK conditions down to H6 (very hardy).

Rhubarb (Rheum palmatum 'Bowles' Variety') is a perennial to 3.0 m with pink flowers in June–July, best in full sun on moist loamy or clay soils.

Rheum palmatum 'Bowles' Variety'

Rhubarb | Rheum palmatum 'Bowles' Variety'

Rheum palmatum tanguticum is a perennial in the Polygonaceae that reaches about 2.0 m and is cultivated as an ornamental for borders. It flowers in June to July, producing pink blooms above the foliage. Plant in full sun on loamy or clay soil that stays moist but drains freely. Wear gloves and other protective equipment when handling because the plant is harmful if eaten.

Tangut rhubarb (Rheum palmatum tanguticum) is a fully hardy perennial to 2.0 m from China that flowers in June–July and suits sunny, moist loamy or clay.

Rheum palmatum tanguticum

Tangut rhubarb | Rheum palmatum tanguticum

Rheum webbianum is a species of herbaceous perennial rhubarb-relative in the family Polygonaceae from the southwestern Himalayan region, known in (Indian) English as Indian rhubarb, Gilgiti rhubarb or small Himalayan rhubarb. In the wild it grows across Nepal, Pakistan, Tibet and West Himalaya. Grow it in full sun and partial shade and loam soil. In UK gardens it is very hardy across most of the UK (RHS H6). It works well for architectural, cottage and informal garden, wildlife gardens and flower borders and beds. It tolerates acid and neutral soils, moist but well-drained conditions and south-facing, east-facing, north-facing and west-facing aspects. Plant in well-drained soil. Water during establishment.

Small Himalayan rhubarb (Rheum webbianum) is a robust herbaceous perennial belonging to the Polygonaceae family. Known also as Gilgiti rhubarb, it features substantial foliage and tall stems that bear clusters of small flowers, offering an intriguing addition to any botanical collection.

https://en.wikipedia.org/wiki/Rheum_webbianum

Rheum webbianum

Small Himalayan rhubarb | Rheum webbianum

Rheum x hybridum 'Poulton's Pride' is a bushy cultivar of rhubarb, a genus of sturdy herbaceous perennials known for their large foliage and tall stems with clusters of small flowers. This deciduous plant thrives in full sun or partial shade and prefers fertile, moist but well-drained loam soil with an acid to neutral pH. Suitable for a variety of garden settings including architectural, cottage, and wildlife gardens, it is hardy to UK zone H6. Best propagated by division in spring, 'Poulton's Pride' offers seasonal interest in both spring and summer.

Rhubarb 'Poulton's Pride' is a hardy, bushy perennial with large foliage and tall stems, ideal for architectural and wildlife gardens in spring and summer.

Rheum x hybridum 'Poulton's Pride'

Rhubarb 'Poulton's Pride' | Rheum x hybridum 'Poulton's Pride'

Rumex conglomeratus, commonly known as clustered dock or sharp dock, is a herbaceous perennial in the Polygonaceae family. This clump-forming plant has a columnar upright habit with creeping rhizomes and a taproot, producing deciduous, primarily basal leaves. It thrives in full sun or partial shade and adapts to a variety of soil types including chalk, clay, loam, and sand, with a preference for fertile, moist conditions. Flowering in summer and autumn, it displays upright panicles of small flowers that develop into reddish-brown, triangular fruits, making it suitable for cottage gardens, wildlife areas, and wildflower meadows.

Rumex conglomeratus, or clustered dock, is a hardy herbaceous perennial with a columnar habit, ideal for wildflower meadows and cottage gardens in summer and

Rumex conglomeratus

Clustered dock | Rumex conglomeratus

Rumex sanguineus, commonly known as wood dock or bloody dock, is a herbaceous perennial in the Polygonaceae family. It has a columnar upright habit, growing to between 0.5 and 1 metre in height with a spread of 0.1 to 0.5 metres. This deciduous plant reaches its full height within 2 to 5 years and thrives in full sun on south- or west-facing aspects. It tolerates a range of soil types including chalk, clay, loam, and sand, with well-drained conditions and a pH that can be acid, alkaline, or neutral. It is adaptable to both exposed and sheltered locations.

Rumex sanguineus (wood dock) is a herbaceous perennial with a columnar upright habit, growing up to 1m tall, thriving in full sun.

The docks and sorrels, genus Rumex, are a genus of about 200 species of annual, biennial, and perennial herbs in the buckwheat family, Polygonaceae. Members of this genus are common perennial herbs with a worldwide native distribution in temperate and subtropical climates.

Rumex sanguineus

Wood dock | Rumex sanguineus

Tovara virginiana is a perennial in the Polygonaceae native to eastern North America that performs reliably in partial shade and shade. It accepts loamy, sandy or clay soils across an acidic to alkaline pH range and prefers moist yet well-drained conditions. Plant on north, east or west aspects in sheltered or semi-exposed spots where it can naturalise in woodland and shade gardens.

Jumpseed (Tovara virginiana) thrives in partial shade on moist, well-drained loamy, sandy or clay soils and suits woodland and shade gardens.

https://en.wikipedia.org/wiki/Persicaria_virginiana

Persicaria is a genus of herbaceous flowering plants in the knotweed family, Polygonaceae. Plants of the genus are known commonly as knotweeds or smartweeds.

Tovara virginiana

Jumpseed | Tovara virginiana

Tovara virginiana var. filiformis is a perennial in the Polygonaceae notable for seedpods that can 'jump' when disturbed. It is unusually shade-tolerant for a genus that mainly prefers sun and flowers from midsummer into early autumn. Inflorescences are slender stalks of small white to greenish-white flowers. Leaves are larger and more oval than in most related species and can show a chevron-shaped marking on some leaves.

Jumpseed (Tovara virginiana var. filiformis) is a shade-tolerant perennial with midsummer–autumn white flowers and seedpods that 'jump' when disturbed.

Tovara virginiana var. filiformis

Jumpseed | Tovara virginiana var. filiformis

Tovara virginiana var. filiformis 'Painter's Palette' is a shade-tolerant perennial in the Polygonaceae, notable for its slender flowering stalks and seeds that can 'jump' when a ripe pod is disturbed. It flowers from midsummer into early autumn with small white to greenish-white blooms. Leaves are larger and more oval than many relatives and may show chevron-like markings on some leaves. Cultivars and garden selections often differ noticeably from wild plants.

Jumpseed Tovara virginiana var. filiformis 'Painter's Palette' is a shade-tolerant perennial with midsummer white to greenish-white flowers and.

Tovara virginiana var. filiformis 'Painter's Palette'

Jumpseed | Tovara virginiana var. filiformis 'Painter's Palette'

Tovara virginiana var. filiformis 'Variegata' is a shade-tolerant perennial in the Polygonaceae that is noted for the way its ripe seedpods can 'jump' when brushed. It carries small white to greenish-white flowers on slender, wiry stems through mid to late summer. Leaves are relatively large and oval, often with a chevron-shaped marking, and garden selections show more variation than wild plants.

Jumpseed Tovara virginiana var. filiformis 'Variegata' is a shade-tolerant Polygonaceae perennial with small white to greenish-white flowers in mid to.