Sophora japonica Seeds | Japanese Pagoda Tree
LATIN NAME: Sophora japonica
COMMON NAME: Japanese Pagoda Tree
Plant Profile
Sophora japonica, better known as Japanese Pagoda Tree, is a tree in the pea family. The Japanese pagoda tree pearls broad, rounded crown with pinnate, dark-green leaves and long, loose clusters of creamy-white, pea-shaped flowers that open through late summer, pods of small, brown seeds following and hanging through the winter. It stands cold, wind, and city air well. It likes sun, and deep, moist, well-drained soil. The ratio of effort to reward here is about as good as gardening gets.
Science & Biotechnology
The pagoda tree’s flower buds (huai mi) are one of the world’s principal industrial sources of rutin, with the flavonoid comprising up to about 20 per cent of the dried buds; the semi-synthetic derivative troxerutin, made from it, is used in Europe for chronic venous insufficiency. Rutin and quercetin strengthen capillaries and reduce their permeability, which matches the drug’s traditional use for bleeding haemorrhoids and blood-streaked stool. The Chinese Pharmacopoeia lists both the flower bud and the fruit. Note that the seeds and pods are considered more toxic and are not the medicinal part.
Seed science, comparative botany and horticultural selection all touch on Sophora japonica, a representative of the pea family with clear practical value. In pea family, pagoda tree has a long, honoured record in studies of temple trees and street trees, and species appears in research on bud chemistry and city-air tolerance. Interest from collectors and breeders has never lapsed, and good seed continues to circulate.
Uses & Benefits
Beyond its ornamental appeal, Japanese Pagoda Tree has the practical versatility that makes a plant worth growing from seed year after year. In avenue and temple garden, the Japanese pagoda tree pearls crown with white flowers. Creamy clusters feed bees late in season, buds and flowers have served traditional preparations for generations, and hard wood serves furniture and the carving. It stands city air well and grows in deep, moist, well-drained, sunny ground. After the first season it asks for very little beyond a place that suits it.
Sophora is a pharmacopoeia in itself: Sophora flavescens root, Ku Shen, is a major Chinese heat-clearing herb for skin and gut, its matrine alkaloids widely studied, while the pagoda tree’s flower buds, Huai Mi, supply rutin by the ton for vascular supplements.
Growing from Seed
Japanese Pagoda Tree is one of those generous plants that come along well from seed. Broadcast the seed thinly over a fine, free-draining compost, sieve a little more compost on top, and water with a fine rose. Prick the seedlings out once they are large enough to handle, grow them on in bright light, and plant out when conditions allow.
Our Take
It is a solid representative of the Sophora group, true to type from seed. Beginners will find it patient of imperfect technique.
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