Diascia rigescens aka Stiff Twinspur

Diascia rigescens, or stiff twinspur, belongs to the Scrophulariaceae family. It comes from South Africa, from the Eastern Cape to southern KwaZulu-Natal. Kew records it as a subshrub from a subtropical climate. The RHS describes its garden form as a spreading perennial. It is not native to Britain or Ireland. Its low growth suits planting near the front of beds.

The plant forms a mat of light green leaves. Each leaf has a broad, egg-like outline. Its semi-evergreen foliage retains some leaves rather than losing them all. Upright flower spikes rise above this low mat of leaves. The flowers are salmon pink, and each has two spurs. Flowering stems reach about 1.5 feet [0.45 metres] tall. Garden plants reach up to 1.6 feet [0.5 metres] in height and spread. The RHS gives two to five years to reach full size.

Grow this plant in full sun and fertile soil. The soil should hold moisture but let excess water drain. Chalk, loam and sand all appear among its suitable soils. It accepts acidic, neutral and alkaline conditions. East-, south- and west-facing sites can suit its needs. The RHS lists both sheltered and exposed growing sites. Its H3 rating suits coastal and relatively mild UK areas. That rating covers minimum temperatures from 23 to 34°F [−5 to 1°C]. It does not imply hardiness throughout colder parts of Britain.

Its spreading form has several uses in small garden spaces. The RHS recommends it for bed edges and flower borders. It also suits rock gardens, patios and pots. Planting schemes can include city courtyards or informal cottage gardens. In containers, keep the same moist, well-drained growing conditions. Water during dry spells rather than letting the soil stay dry. Remove spent flowers to help extend the flowering display. The source gives no clear calendar for its flowering season.

Slugs and snails may damage the plant, though diseases seldom cause trouble. Grow new plants from seed or from softwood cuttings. Sow seed when ripe or during early spring. Take softwood cuttings in summer. The supplied sources give no edible uses or medicinal uses. They also provide no toxicity assessment for people or pets.