Reseda luteola

Biennial, sometimes short-lived perennial, from the Resedaceae family, native to Southern and Central Europe, the Mediterranean basin, and the Middle East, naturalized far beyond its original range. It colonizes wastelands, rubble, path edges, old walls, dry and stony embankments, calcareous wastelands, from sea level to medium altitudes.

In the first year, it develops a basal rosette of narrow, entire or slightly wavy, dark green and glossy lanceolate leaves. In the second year, it raises upright, firm, and branched stems from the base, generally reaching 60 to 120 cm, bearing long, very dense, narrow, and tapered spiciform clusters covered with small pale yellow-green flowers with four unequal petals.

In its natural habitat, its flowering extends from June to August.

This plant has been known since antiquity as a source of an intense yellow dye, luteolin, extracted from the entire aerial part. It was widely cultivated for this purpose in Europe until the 19th century for dyeing textiles, notably wool and silk, under the name of weld or dyer's weed.

It thrives in any well-drained, poor, and dry soil, in full light. It self-seeds spontaneously and requires little maintenance.