Dictamnus dasycarpus Seeds | Densefruit Burning Bush
LATIN NAME: Dictamnus dasycarpus
COMMON NAME: Densefruit Burning Bush
Plant Profile
Dense-fruited dittany is the northern form of the burning bush, a herbaceous perennial of sixty to eighty centimetres whose seed capsules are packed so tightly along the spike that the head looks like a knot of beads. The flowers are pale lilac and the foliage smells of lemon when it is brushed.
It grows on stony slopes and at forest edges in Liaoning, Inner Mongolia and the Russian Far East, in ground that dries out in June. In cultivation it is grown both as an ornamental and as a medicinal root crop, and the two trades use the same plant for different parts: the gardener wants the flower, the herb buyer wants the bark of the root.
Science & Biotechnology
The root bark, bai xian pi, contains dictamnine, obakunone and a group of limonoids, and it is one of the herbs listed in the Chinese Pharmacopoeia with a defined thin-layer identification. Dictamnine is a furanquinoline alkaloid, a different class from the furanocoumarins of the leaf, and the two are often confused in popular writing about the plant.
Dictamnine is also the reason the herb needs care. It intercalates into DNA and is phototoxic and mutagenic in laboratory systems, and there are published reports of liver enzyme elevation in patients taking multi-herb formulas that include it. The herb is not a candidate for long unsupervised use, and it is contraindicated in pregnancy in the standard references.
Uses & Benefits
The root bark is used in decoction and in washes for skin complaints: eczema, fungal infection of the feet and pruritus, usually with other herbs and often applied as well as taken. It is one of the ingredients in the classical formula that bears its name, and it appears in the pharmacopoeia as a treatment for damp-heat patterns rather than for any single disease.
The ornamental trade sells the plant under the burning bush name, and the seed heads are used in dried arrangements since the capsules hold their shape and their scent for months. The root is not sold as a vegetable, and the leaf is not eaten: the same furan compounds that make the plant interesting make it a poor kitchen herb.
Growing from Seed
Seed needs a warm period followed by cold, and sowing in late summer in a pot left outdoors gives the most reliable germination, often in the second spring. Sow thinly, cover lightly and keep the pot moist but not wet, since the seed rots in stagnant compost.
Plant out on a ridge or a raised bed in full sun, at forty centimetres by twenty-five, and keep the rows weeded for the first two seasons. Roots are lifted in the fourth or fifth autumn, washed and slit lengthwise, and the bark is stripped and dried in the shade. Yields are low: a square metre gives a few hundred grams of dry bark, which is why the price holds.
Our Take
A dual-purpose plant, grown for its scented flower or for a root bark that deserves respect. Use the herb short-term and not in pregnancy.
Related Reading
Gardeners who grow Densefruit Burning Bush often pair it with these related subjects: