Erysimum sp

Brassicaceae. This plant, photographed in the Picos de Europa massif (Cantabrian Mountains, northern Spain), could not be definitively identified at the species level. Several Erysimum are reported in this limestone massif, including Erysimum cantabricum and Erysimum gorbeanum, endemic or subendemic to the Cantabrian region, but a reliable identification from photographs alone remains delicate without examination of herbarium material. The designation Erysimum sp. is therefore maintained here as a precaution.

The plant forms a widely spread and very dense cushion, remarkably floriferous, about fifteen centimeters in height. The foliage, narrow and dark green, is practically invisible under the abundance of flowers at the time of full anthesis. The tetrapetalous flowers are a bright and clear yellow, arranged in numerous and tight clusters that completely cover the surface of the cushion, giving it an almost monochrome appearance of remarkable intensity.

In its natural environment, its flowering likely extends from May to July depending on altitude and exposure, on the sunny limestone screes and cliffs of the montane and subalpine levels of the Picos de Europa.

In cultivation, as with most mountain Erysimum, a very well-drained, limestone or mixed soil, in full light, with protection against stagnant winter moisture, is the essential condition. Its vigor and floral generosity make it a particularly attractive plant for rock gardens, provided its taxonomic identity is one day clarified.