Selected form of Raoulia australis, a ground-covering perennial from the Asteraceae family, native to New Zealand. Like the type species, it colonizes gravelly and rocky well-drained substrates and is cultivated under the same conditions of open and sunny rock gardens.
This form constitutes an even more miniature carpet than the type species, strictly flat on the ground, not exceeding 1 cm in height, with slow progression. The leaves are tiny, tightly packed together and covered with a silvery-gray tomentum that gives the whole a texture reminiscent of a lichen or mineral moss.
What immediately distinguishes 'Calf' is the combination of this particularly reduced format and an abundant and clustered flowering, forming a dense area of bright yellow to yellow-green capitula clearly visible in the center of the carpet, which contrasts sharply with the silvery gray foliage. In its natural habitat, the flowering of the type species extends from November to January; in cultivation in the northern hemisphere, it generally occurs from May to July.
It requires a very well-drained, poor, and gravelly soil, in full sun exposure. Stagnant winter moisture is harmful to it. Cultivation in a trough, in a draining rock garden, or between slabs suits it perfectly.