Boehmeria nivea Seeds | Ramie
LATIN NAME: Boehmeria nivea
COMMON NAME: Ramie, China Grass
Plant Profile
Degumming is where ramie differs from every other bast crop. Traditionally the fresh canes are stripped of bark and the ribbons boiled in an alkaline bath, sometimes with wood ash, until the gum softens enough to rinse out. Mills do the same with sodium hydroxide, then neutralise and dry. Both routes use a lot of water and energy.
The biotechnological alternative is to let pectin-degrading bacteria do the work. Strains of the genus Bacillus are the classic agents of ramie retting: grown on the cut stems, they secrete pectinases and xylanases that free the fibre bundles with far less alkali. Enzyme preparations built on the same activities are used in cleaner degumming lines.
Science & Biotechnology
The fleshy root and rhizome are a separate crop, dug from established stools rather than from seedling plants. Phenolic acids are the main markers studied in the root: chlorogenic acid and caffeic acid, both widespread in the family. Ramie root also contains polysaccharide fractions, often examined in laboratory work on its non-fibre uses.
The leaves carry protein and a great deal of calcium, and in parts of Asia they are cooked as a green vegetable or ground into a deep green powder that colours and flavours sweet foods. The same leaf protein makes ramie a useful forage crop, cut young and fed fresh or ensiled. Leaf and fibre come from different plantings, since the cutting regimes do not match.
Uses & Benefits
Ramie has been woven for so long that ordinary retting will not prepare it. Flax stalks rot in a field until the fibre separates, but ramie bast is so heavily cemented that water leaves it bound to its own gums. Every culture that used it had to invent a chemical or microbial step first, which is why it is grown on countless small plots yet rarely appears in mass-market textiles.
The useful fibre sits in the phloem of the stem as bundles of long, thick-walled cells glued by pectin, hemicellulose and lignin. Individual ramie cells are the longest of any commercial plant fibre, which gives the yarn its lustre and its strength, and also its stiffness. Nearly pure cellulose once cleaned, it resists rot better than cotton and takes dye badly, having little amorphous structure to soak it up.
The leaf is broad, heart-shaped and coarsely toothed, green above and covered beneath with a dense felt of white hairs that gives the species its name. Unlike its stinging relatives, Boehmeria lacks urticating hairs, but the leaves carry cystoliths, small concretions of calcium carbonate lodged in the epidermal cells. Those crystalline bodies are a routine identification character in the family.
Both sexes occur on one plant, in small greenish clusters in the leaf axils: male flowers lower down with four tepals and four stamens, female flowers above with a tufted stigma. Pollen travels on the wind, so seed from a ramie field varies in every character that matters; growers propagate selected clones instead and treat seed as breeding material.
Ramie yarn is chosen where strength matters more than drape: fishing nets, sewing thread, industrial cordage, upholstery and heavy canvas. It blends well with cotton and wool, holding a crisp shape that neither gives alone, and it appears in fine papers where a long, tough fibre is wanted. A pure ramie garment softens with wear without becoming elastic.
Growing from Seed
Ramie is planted from pieces of stem or rhizome rather than from seed, and the first cut comes in the season after planting.
Left in the ground, a stool thickens into a mat of rhizomes and sends up suckers around its edge, so an established bed can be lifted and split. Division is the quickest way to multiply a good clone, and the pieces are best moved while the plants are dormant. Stools that crowd themselves are worth dividing every few seasons to keep stem size up.
The crop is troubled by root rots in heavy, wet ground, by powdery mildew on crowded foliage and by root-knot nematodes in warm sandy soils. Drainage and rotation are the main defences. Where winters are cold, cut the canes in autumn and cover the crowns with a thick mulch of straw or leaves.
Our Take
Ramie is a crop with a long memory: the first year is all roots, and the stool that looks small in autumn will be a thicket by the next. Plant more stool pieces than you think you need; the outer ones are the ones you will lift later. If bast fibre interests you, the easier crops to start with are flax and hemp, while the nettle family itself is well represented by stinging nettle and the Chinese Urtica fissa.
Related Reading
Gardeners who grow Ramie often pair it with these related subjects: