Polygonum bistorta 'Superba', formerly known as Persicaria bistorta 'Superba' is a fine border plant, a semi-evergreen perennial that produces clusters of small, light pink flowers throughout summer and into autumn.
The flowers are clustered in a cylinder shape on the top of tall flower spikes and the leaves are quite large, broad and bright green.
It likes a moist but well drained soil in sun or partial shade but is adaptable to most soils and conditions, it is ideal for creating groundcover and is also a useful plant for soils that are poorly drained. It will tolerate drier soils but will not flower nearly so well: dry conditions slow it down dramatically.
A mass of these, covered in spikes of flowers in varying shades of pink, is classic as a host of golden daffodils in spring, while in September the mid-green, oblong, shiny leaves make good dense ground cover.
'Superba' is better for the garden than the species because it has larger flowers. Plant in bold swathes to add a vertical dimension to the border through till mid-autumn, the flowers are an important late summer source of nectar for beess.
- Awarded the RHS Award of Garden Merit
Polygonum bistorta 'Superba' has been awarded the Royal Horticultural Society’s Award of Garden Merit (AGM).
Sowing: Sow in late summer/autumn and late winter/late spring.
Sow seeds at temperatures of around 18 to 22°C (64 to 71°F), covering them with a thin layer of compost. The compost should be kept moist but not wet at all times. Germination should start to occur between 21 and 60 days
If germination is slow, you may wish to use the method of stratification to mimic the seed going through the seasons: Place the tray into a fridge for 4 weeks (Fridges are usually set at 4°C, the ideal 'Winter' temperature, then bring out and place in an area that mimics spring: at 5 to 2°C (41 to 53°F)
Prick out each seedling as it becomes large enough to handle, transplant into 7.5cm (3in) pots or trays. After the last expected frosts, gradually acclimatise to outdoor conditions for 10 to15 days before planting out into their permanent positions, space at least 30cm (12in) apart.
Grow in moist soil that does not dry out, in full sun or partial shade. You may not wish to plant too close to a pond or water, as it can become invasive on very damp soil. Propagate by division in spring or autumn.
Cottage/Informal Garden, Flowers Borders and Beds, Garden Edging, Ground Cover or Rock Garden.
The species Polygonum bistorta is native to parts of Northern Europe, Siberia, Japan and Western Asia to the Himalayas. Formerly cultivated as a culinary and medicinal plant in the UK and Ireland, it was considered a declining species by the early 20th century. It can be found in areas of northern Ireland, the northern England to the south of Scotland.
Persicaria is the medieval name given to Bistort. It is taken from the Latin persica meaning 'peach', alluding to the shape of the leaves. In ancient times a peach was called persike or persica meaning 'Persian apple'. A fruit that reached Europe from China by way of Persia.
The root-stock of bistort as it appears in commerce, is dark brown and about 5cm (2in) long and 1cm (3/5in) broad. It is twice bent, as in the letter ‘S’.
The name bistort comes from Latin word elements bis meaning 'twice' and torta meaning 'twisted', so 'twice-twisted'.
An old local name, 'Twice-Writhen,' being a literal translation of the Latin. Its twisted nature is also the origin of the names Snakeroot, Adderwort and Snakeweed.
It was at one time called Serpentaria, Columbrina, Dracunculus and Serpentary Dragonwort, and has been thought to be the Oxylanathum Britannicum and Limonium of the ancients.
The variety name superbus simply means 'superb', and refers to the large flower heads.
- Awarded the RHS Award of Garden Merit
- Additional Information
Packet Size 180 mg Average Seed Count 25 Seeds Seed Form Natural Seeds per gram 120 seeds per gram Common Name Formerly Persicaria bistorta 'Superba' Other Common Names Fleece Flower Family Polygonaceae Genus Polygonum Species bistorta Cultivar Superba Synonym Persicaria orientale, Polygonum orientale Hardiness Hardy Perennial Flowers Pink flowers are clustered in a cylinder shape on the top of tall flower spikes. Natural Flower Time May to August Foliage Semi-evergreen. Bronze in Autumn. Height 75cm (30in) Spread 90cm (36in) Position Full sun or light shade Aspect All aspects. Exposed or Sheltered. Soil Nutritious and moist ideal, but does tolerate dry soils. Time to Sow Late winter/late spring or late summer/autumn. Germination 21 to 60 days