Astragalus gummifer aka Tragacanth

Astragalus gummifer is a small evergreen subshrub in the pea family, Fabaceae. Its native range runs from eastern Türkiye to Lebanon and northwestern Iran. Records also place it in Syria and Iraq. It grows in temperate regions on dry mountain slopes and in valleys. Its habitats include upland woods and grassland. In Iraq, records place it at 3,940–8,530 feet [1,200–2,600 metres].

Plants reach about 1 foot [0.3 metres] tall and wide. Growth proceeds at a moderate pace. The stems become woody, but may die back near ground level each winter. This gives the plant a low, compact form. Root nodules house bacteria that fix nitrogen from the air. This partnership can help the plant grow in poor soil. Each flower has both male and female organs. Bees, moths, and butterflies pollinate the flowers. Plants can also set seed through self-fertilisation.

Grow this species in full sun and dry, well-drained soil. Sandy and loamy soils suit it. It accepts poor ground and a broad soil pH range. Reported tolerance spans pH 3.2–7.8. Shade does not suit it. Plants For A Future lists USDA zones 7–10. It also reports cold tolerance of about 14–23°F [-10 to -5°C]. Winter wet may cause trouble even where plants withstand the cold. Roots dislike disturbance, so plant young specimens in their final place.

The roots and stems yield tragacanth gum. Some gum seeps out without cutting, including from damaged stems. Growers can also collect it by making cuts below ground level. Food makers use the gum to thicken sweets, dressings, and sauces. It is an approved food additive, E413. This use concerns the gum, not the whole plant. The evidence does not establish that other parts are edible. Nor does it establish a species-specific toxicity rating.

Tragacanth also thickens dyes, glues, inks, and watercolours. It helps bind paper and gives fabrics a finish. People burn the gum and stems as incense. Traditional medicinal uses include burn dressings and soothing preparations. Lozenges use the gum to hold their ingredients together. Seed offers a means of propagation, though germination can be uneven. Fresh seed or treated stored seed may take four to nine weeks or longer to sprout.