Ononis spinosa aka Spiny Restharrow

Ononis spinosa, or spiny restharrow, belongs to the pea family, Fabaceae. It grows wild across much of Europe, including Britain. Its native range also covers North Africa and temperate Asia. It grows in chalk and limestone grassland and on stony slopes. Open pine woods also provide a home for this plant. These sites often have dry, stony ground.

This upright plant forms a small shrub with a woody base. It can also grow as a woody-based perennial. It keeps some of its leaves through winter. Plants reach about 2 feet [0.6 metres] in height. The listed garden range is 1.6–3.3 feet [0.5–1 metre]. Spread ranges from 0.3–1.6 feet [0.1–0.5 metres]. Stiff stems bear spines and small leaves in groups of three. Each leaf has an oval to narrow oval shape. Pea-like flowers grow along the stems during summer. Their colours include pink, purple and blue.

Give it full sun and soil that drains well. Chalk, loam and sand suit it, with neutral or alkaline soil. Choose a sheltered spot facing south or west. It suits sunny banks, rock gardens and gravel beds. It also fits informal borders and beds beside south-facing walls. RHS rates its hardiness as H6. This covers winter lows near -4 to 5°F [-20 to -15°C]. Plants For A Future lists USDA zones 5–9. Plants reach their full size in two to five years.

RHS reports few pest or disease problems and no pruning need. Plants may have short lives, so raise replacements at intervals. Sow seeds in pots in an open frame during autumn. Seeds may need scarifying before sowing. Another option is to take softwood cuttings in early summer. Plants For A Future lists this species as a nitrogen fixer. It also records meadow use and no weed potential.

Plants For A Future lists flowers, leaves, roots and shoots as edible. Young shoots can be cooked as a green vegetable. Raw flowers can serve as a salad garnish. Roots can be chewed for a taste like liquorice. The source reports no known hazards, but this does not prove universal safety. It also records traditional medicinal uses for roots, leaves and flowers. These include use for coughs and urinary complaints. Such records describe past use, not proof of treatment benefits.