Serratula tinctoria var. seoanei

Serratula tinctoria var. seoanei, also known as Seoane's Saw-wort or Galician Saw-wort, is a small perennial plant that grows naturally in heathlands and lowlands but it is not well-known among gardeners. Its prolonged and late flowering period, with beautiful mauve to purplish-pink flowers, reminiscent of centaureas, is a welcome sight when flowers are scarce. It is hardy, but does require a sunny exposure and well-drained soil to withstand harsh and humid winters. These are conditions it will find in rock gardens, on slopes, or in gravel beds, among other unassuming plants, in a natural garden.

Serratulas are plants in the Asteraceae family, just like thistles and cornflowers. Serratula seoanei is a subspecies of the Dyer's Saw-wort (Serratula tinctoria), endemic to the extreme southwest of Europe. It can be found in Portugal, Spain, and France, always along the Atlantic coast. It thrives in acidic heathlands with plenty of sunlight, and it can tolerate dry summers.

This is a perennial herbaceous plant with an underground root system, whose vegetation disappears in winter and reappears in spring. It first develops a clump of long, dark green, greyish leaves divided into narrow lobes, with toothed edges. At maturity, this saw-wort will measure about 20-30 cm (8-12in) in height when in flower, and spread about 30-40 cm (12-16in) on the ground. The flowering period lasts from late summer to early autumn, from August-September to October-November. Branched stems rise from the foliage clump bearing inflorescences in wide heads measuring 1.5 to 2 cm (1in). Each head is tightly enclosed in a purple calyx and composed of lots of small flowers ranging from mauve to purplish-pink, loved by pollinating insects. Flowering is followed by silky achenes, which can self-sow.

This is a hardy perennial plant that tolerates dry conditions in summer. It just needs a sunny location and well-drained soil, preferably non-chalky and poor. This wild, charming saw-wort needs no special care. It adds structure to rock gardens and sunny slopes. It can be paired with small thistles like Echinops, saxatile alchemilla, ornamental grasses (Stipa, Muhlenbergia capillaris, Carex comans), or even with cordifolius Little Carlow asters. Its beautiful mauve flowers accompany those of shrubby salvias in bright pink, red, or blue until late in the season.

Dyer's Saw-wort, as its name suggests, was once used to dye fabrics: its foliage contains a yellow pigment.