Gray or green thorny bush, usually with no more than 0.5 m high, which like sun and is quite resistant to drought, cold and extreme temperature ranges. Blooms in June-July, releasing a sweet smell similar to honey. The inflorescences, formed by 5-8 flowers (sometimes more), have a yellow corolla, resembling those of the gorse. The fruit is a hairy spindle-shaped pod.

It has a cushion shape, as an adaptation, being so dense and low as the cold winds are stronger. Areas with this species are called ‘caldoreinais’ in Portuguese. Forms sparsely communities.

It is a species characteristic of natural habitat "4090 - Endemic oro-Mediterranean heaths with gorse" that has very interesting species.

In the north and center of Portugal in ‘piornais’ (are with brooms Retama spp.) and other thorny bushes in mountain areas; characteristic of rocky ridges with skeletal soils (e.g. very thin soils), especially in areas with granite and quartzite rocks, desolate in winter by strong, cold winds. Often on the top of narrow valleys where the wind is greater due to pressure differences. Between 700 m to 1750 meters above sea level, but in International Douro valley can be found at about 500 meters high.