Greek chelone— tortoise, the flower purportedly resembling the tortoise head.

Perennial herbs, hairless. Leaves opposite, saw-toothed. Flowers in spike-like clusters, white, red or purple; summer. Sepals 5. Corolla bent downwards, 2-lipped, upper lip 2-lobed, lower 3-lobed and bearded inside. Stamens 5, 4 fertile, 1 sterile, woolly. Fruit a capsule; seeds winged.

Grown for the erect habit and flower spikes.

Seed, division or softwood cuttings.

Some species are used medicinally to treat worms.

Closely related to Penstemon but has winged seeds and the sterile stamen shorter than the fertile ones.

5-6 species from N America.

Source: Spencer, R. (2002). Scrophulariaceae. In: Spencer, R.. Horticultural Flora of South-eastern Australia. Volume 4. Flowering plants. Dicotyledons. Part 3. The identification of garden and cultivated plants. University of New South Wales Press.