How big does Red bistort grow?

About 1.2 m × 1.2 m after ten years (height × width). Its ultimate size is 0.7–1.2 m × 0.9–1.2 m.

What soil does Red bistort grow in?

It tolerates these soils: average garden soil, clay.

Is Red bistort hardy?

Hardy down to -34 °C (USDA zone 4, RHS H7). It gets through winter in every part of the country.

When does Red bistort flower?

Flowering: June–October, red, pink, white.

How much water does Red bistort need?

Water need: medium. Drought tolerance: low.

How much does Red bistort cost?

It sells for roughly €6 to €13 in local shops, depending on size.

Red bistort

Persicaria amplexicaulis

Red bistort (Persicaria amplexicaulis) is a perennial that reaches 1.2 m × 1.2 m after ten years. Light: full sun, part shade. Hardy down to -34 °C. Drought tolerance: low. Sold in local shops from about €6.

Illustration of Red bistort — An illustration of the typical shape of the mature plant, not a photo.

What it's good for, and what it isn't

Red bistort is one of the longest-flowering perennials: from early summer until the frosts its dense, leafy mound keeps producing slender spikes of red (or, depending on the cultivar, pink or white) flowers that are alive with pollinators. It is worth knowing that it is not the same thing as the aggressively spreading giant knotweeds: this is a well-behaved, clump-forming garden plant whose clump widens only slowly, though it does need a good metre of space when mature. It looks best in sun or part shade in moist soil and dislikes drying out.

Watch out for

It has no serious pests or diseases. In Central Europe its weak point is summer heat and drought: in drying soil and full sun the leaves wilt and scorch and flowering stops, so in a dry garden plant it only where you can water or in part shade. Tall stems may flop in strong wind, and slugs and aphids turn up occasionally.

Key facts

Light: Full sun, Part shade
Water need: Medium
Care: Low
Size after 10 years: 1.2 m × 1.2 m
Hardiness: down to -34 °C
Foliage: Deciduous
Flowering: J F M A M J J A S O N D June–October, red, pink, white

Group	Perennial
Light	Full sun, Part shade
Size after 10 years	1.2 m × 1.2 m
Ultimate size	0.7–1.2 m × 0.9–1.2 m
Hardiness	down to -34 °C (USDA 4, RHS H7)
Soil	Average garden soil, Clay
Foliage	Deciduous
Flowering	June–October, red, pink, white
Water need	Medium
Drought tolerance	Low
Maintenance	Low
Root aggressiveness	Low
Suckering	no data
Spreading	Low
Distance from buildings	no data
Distance from paving	no data
Litter	not typical
Planting distance	70 cm
For dogs	no data
For cats	no data
For children	no data
Typical price	from about €6

Toxicity data is for information only. If your pet or child has eaten a plant, contact a vet or a doctor.

Sizes and prices available

The same plant is sold as a small pot and as a specimen several metres tall, and the price follows. Prices are rounded and for guidance only.

Size	Typical price
30-40 cm	approx. €6.60
size not stated	approx. €6 – €13

Frequently asked questions

Data updated: October 8, 2026 · How our data is made

Appears in these lists

Ground cover plants Perennials for part shade Perennials for full sun Perennials that flower all summer Perennials for clay soil Perennials for pollinators Low-maintenance perennials

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