The flowers are produced in whorls on the upper stems, violet-blue or dark purple, tubular or bell-shaped, 1.5–2 cm long, with two lips.
This is an alpine plant best suited to areas with mild summers where nights are cool.
Keep evenly moist and feed once at the start of the growing season with a ration of slow-release fertiliser.
Propagate from seed sown in autumn and exposed to low winter temperatures, or by dividing established clumps in spring.
Horminum pyrenaicum prefers rocky slopes, pastures and grasslands at elevation of 1,400–2,500 metres (4,600–8,200 ft) above sea level.