Geography and distribution
The spiny strawberry cactus is found in Mexico in the states of Chihuahua, Coahuila, Durango, Nuevo León, San Luis Potosí and Zacatecas, and in the USA in New Mexico and Texas. Echinocereus stramineus occurs at 600 to 1,600 metres above sea level.
Echinocereus stramineus is a low-growing cactus with dense clusters of stems covered in long white to straw-coloured spines, bearing large magenta flowers followed by edible strawberry-flavoured fruits.
The plant is densely branched at the base, clumping to form hemispherical mounds of up to 500 stems, reaching a metre or more in diameter. The individual stems are up to 45 cm long and 8 cm in diameter near the base, tapering gradually towards the tip. There are 10 to 17 stem ribs, which are somewhat tuberculate (knobbly). Areoles (spine clusters) are 7 to 15 mm apart on the ribs, and are white and woolly at first. The spines are straw-coloured, glassy white or pinkish. There are two to four central spines, which are each up to 8.7 cm long. There are seven to 14 radial spines, which are each up to 3 cm long.
The flowers are broadly funnel-shaped, and up to 12.5 cm long and wide. The flowers are a lively magenta, and are made up of numerous perianth-segments (rings of non-fertile petal-like parts surrounding the fertile organs). The flowers are up to 6 cm long and 12.5 cm broad. The pericarpel (ovary immersed in floral stem tissue) bears scales with glassy white spines of up to 3 cm long in their axils. The stamens are up to 1 cm long, with purplish red filaments and yellow anthers. The style is reddish and up to 2.7 cm long and 2.5 mm thick. The style opens up at the tip into 10 to 13, 8 mm long deep green stigma-lobes.
The fruit are spheres of about 5 cm diameter and are spiny until ripe. Upon ripening the fruit lose their spines and turn red, aromatic and very fleshy. These edible fruits taste of strawberries and contain blackish seeds of up to 1.5 mm diameter.
Threats and conservation
Echinocereus stramineus is in the IUCN (International Union for Conservation of Nature) category of Least Concern, but is potentially threatened by trampling from grazing animals or mining of the rocks upon which it grows, though neither of these threats is likely to be significant over its entire range.
The edible, strawberry-flavoured fruits are sometimes collected from wild populations. The fruits can be eaten raw or made into jellies.
In temperate regions Echinocereus species such as this require cultivation under glass in full sun, but with ample ventilation. They are best grown in a broad shallow pot, to allow the clustering branches sufficient lateral spread. They should be planted in well-draining largely mineral compost and watered from April until September whenever the compost has dried out. A cool winter rest is essential if flower-buds are to be produced the following spring. If dehydrated, the plant can withstand temperatures down to 0 °C during this winter rest. Flowering on plants less than 30 cm in diameter is uncommon.
Propagation can be achieved by detached branches, which can be rooted when placed upon a sandy substrate, following adequate healing of any cut surfaces in a dry airy place. Echinocereus stramineus can also be raised from seed in the manner of other small-seeded cacti. The seeds should be sown on the surface of finely sieved compost and placed under a glass or transparent plastic cover in a temperature of 20 °C.
Strawberry cactus at Kew
Echinocereus stramineus is likely to be exhibited in Kew's Princess of Wales Conservatory if it flowers in spring-summer.