Polygonum orientale Seeds | Prince Feather
LATIN NAME: Polygonum orientale
COMMON NAME: Prince Feather
Plant Profile
Prince’s feather is a tall, fast annual with arching sprays of small rose-pink flowers that hang like a brush from the stem tips. Plants reach 1.5-2 m in a season, with large heart-shaped leaves and hollow, bamboo-like stems that sway in any breeze.
Flowering begins in July and continues until frost, and the sprays lengthen as they open, so a plant in August is covered in dangling pink tassels. The effect is soft rather than bold, and it works best at the back of a border where the height can be used without exposing the floppy lower stems.
The species is native to east Asia and has been grown in European gardens since the eighteenth century. It is a plant of damp ground and riverbanks in the wild, and it behaves accordingly in cultivation: it wants moisture, it grows fast, and it self-sows prolifically in bare wet soil.
Science & Biotechnology
Polygonum orientale, now usually placed in Persicaria, is a member of the knotweed family, and it shares the family’s chemistry of tannins, flavonoids and anthraquinones. The leaves are astringent when chewed, which is the taste of the tannins, and extracts of related species have shown antioxidant and antimicrobial activity in laboratory work.
The genus has a complicated taxonomic history. Many species were moved to Persicaria and Fallopia on molecular evidence, and Prince’s feather is listed under both names depending on the catalogue and the year. The plant is the same; only the label has changed.
There is one caution attached to the family. The knotweeds include some of the most invasive plants in temperate agriculture, and while Prince’s feather is an annual that dies at frost and does not spread by rhizome, it seeds heavily. In a damp garden it can become a fixture whether you want it or not.
Uses & Benefits
Prince’s feather is a back-of-border plant for a damp spot, where its height and its movement are more valuable than any individual flower. It suits a wild garden, a fence line or the edge of a pond, and it combines well with asters, helianthus and the taller grasses.
The flowers are useful in large arrangements, where the arching sprays give a loose, natural line that most cut flowers cannot. They last four or five days in water and dry reasonably well. In Asia the plant has a history of medicinal use as an astringent, and the seed has been used as a famine food after processing, though it is not a crop worth growing for the kitchen.
Growing from Seed
Sow in April or May at 18-20°C, covering the seed lightly. Germination is fast, usually one to two weeks, and the seedlings grow away strongly. The plant resents root disturbance once established, so sow in individual pots or direct where it is to grow.
Set out at 60 cm apart in full sun or light shade, in soil that holds moisture. Water regularly through the first two months, since a check in growth produces a stunted plant that flowers late. No feeding is needed on decent ground. Stake or place against a fence, and cut the stems to the ground after frost. Leave a few seed heads if you want the self-sown seedlings that make the plant permanent.
Our Take
A tall, soft-textured annual for the damp back of a border, best used where its self-sowing can be tolerated rather than fought.
Related Reading
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