Sanguisorba obtusa (Japanese burnet) — Clump forming

Overview

Sanguisorba obtusa is a clump forming perennial in the genus Sanguisorba, part of the Rosaceae family, with deciduous foliage. It typically grows around 1.0 m tall. Sanguisorba obtusa grows best in full sun, and tolerates most soils and any pH. Its UK hardiness is rated H7. Suggested uses include cottage and informal garden, prairie planting, wildflower meadow, low maintenance and flower borders and beds. It is native to Japan to Russia.

About the genus

Sanguisorba is a genus of flowering plants in the family Rosaceae native to the temperate regions of the Northern Hemisphere. The common name is burnet.

Wikipedia contributors, "Sanguisorba", CC BY-SA 4.0 — Sanguisorba

In the garden

Sanguisorba obtusa is a herbaceous perennial native to Japan to Russia, valued for its upright, wiry flowering stems that appear above a mound of grey‑green leaves. It flowers from June to August, producing bottle‑brush heads of bright pink that provide movement and structure through the summer months. Give it a sunny site and soils from sandy to loamy or clay; the key is consistent moisture — it tolerates moist to wet ground rather than drought. Hardiness is H7 (fully hardy), and it corresponds to roughly USDA zones 4–9, so plants withstand cold UK winters without winter protection when well sited. Use Japanese Burnet where a tall, airy summer flower is useful: moist borders, rain gardens, pond edges and alongside upright ornamental grasses are appropriate pairings. Because the flowering stems rise well above the foliage, place it where the blooms can be seen rather than buried deep within lower-growing perennials. Expect the stems to sway in light breezes from June to August, giving a subtle architectural rhythm to the border.

Growing conditions

Best soil and position for Sanguisorba

Sunlight: Full sun
Soil type: Sandy, Loamy, Clay
Soil pH: Acid, Alkaline, Neutral
Soil moisture: Moist but well-drained, Wet
Aspect: East-facing, South-facing, West-facing
Exposure: Exposed, Sheltered
UK hardiness: H7

Plant details

Sanguisorba obtusa size, habit and characteristics

Plant type: Perennial
Habit: Clump forming
Foliage: Deciduous
Height: 1.0 m
Suggested uses: Cottage and informal garden, Prairie planting, Wildflower meadow, Low Maintenance, Flower borders and beds
Native to: Japan to Russia

Care notes

Pruning and caring for Sanguisorba obtusa

Cultivation: Prefers moist, well-drained soil in full sun; tolerates wet conditions; benefits from mulching to retain moisture
Pruning: Cut back after flowering to maintain shape and encourage fresh growth
Propagation: Seed, Division in spring or autumn
Pest resistance: Generally pest-free
Disease resistance: Generally disease-free

Frequently asked questions

How do I grow Sanguisorba obtusa?

Prefers moist, well-drained soil in full sun; tolerates wet conditions; benefits from mulching to retain moisture.

Where is the best place to plant Sanguisorba obtusa?

Sanguisorba obtusa prefers full sun. It suits exposed and sheltered positions.

What soil does Sanguisorba obtusa need?

Sanguisorba obtusa is adaptable and grows happily in most soil types, including sandy, loamy and clay. It is happy in soil of any pH. Aim for soil that stays moist but well-drained to wet.

How do I prune Sanguisorba obtusa?

Cut back after flowering to maintain shape and encourage fresh growth.

How big does Sanguisorba obtusa grow?

Sanguisorba obtusa reaches a height of 1.0 m.

Is Sanguisorba obtusa hardy in the UK?

Sanguisorba obtusa has an RHS hardiness rating of H7, meaning it is fully hardy throughout the UK, tolerating temperatures below -20°C.