PHUOPSIS STYLOSA (TRIN.) G.NICHOLSON – CAUCASIAN CROSSWORT, LARGE-STYLED CROSSWORT OR PHUOPSIS

Phuopsis stylosa (Trin.) G.Nicholson (syn. Crucianella stylosa Trin.) is a perennial herbaceous species in the Madder Family (Rubiaceae). It is native to the Caucasus region, where it grows wild on hillsides and in deciduous woodland areas. Commonly known as Caucasian crosswort, large-styled crosswort, or simply phuopsis, the species has been introduced to Germany, Great Britain, and Ireland, and is widely cultivated elsewhere as an ornamental plant.

The stems of Phuopsis stylosa (Trin.) G.Nicholson are 15 to 20 cm long, prostrate, and form a dense, mat-forming habit. The leaves are light green, lanceolate, and pointed at the tip, arranged in whorls along the entire length of the stem. Large-styled crossword forms small, star-shaped flowers which are grouped into dichasial, head-like cymes measuring 2–3 cm in diameter. They are positioned at the ends of each shoot. Flowering usually begins in May and continues through September, with peak bloom during June, July, and August.

For optimal growth and abundant flowering, Caucasian crosswort (Phuopsis stylosa (Trin.) G.Nicholson) prefers a sunny to partially shaded location, well-drained soil, and moderate moisture. Regular removal of spent flowers encourages the formation of new buds and extends the blooming period. The species is fully hardy in Bulgaria, tolerating minimum temperatures between –28.8°C and –1.2°C. It can be propagated by seed, division in spring, or cuttings in summer.

All parts of Phuopsis stylosa (Trin.) G.Nicholson emit a distinctive aroma, but it is primarily valued for its dense ground-covering foliage and profuse flowering. It is well suited for use as a groundcover, in rock gardens, on slopes, or in fragrant-themed gardens.