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Homalocephala spp.
Chihuahuan Desert and south-central United States
Overview
Homalocephala spp. is a small genus in the cactus family, Cactaceae, centred on H. texensis, the horse crippler, of southern Texas, New Mexico, and the Chihuahuan Desert of northern Mexico. The plant forms a solitary, flattened, disc-shaped body 4-12 inches (10-30 cm) across but only 2-6 inches (5-15 cm) tall, often sitting nearly flush with the ground so that drought or fire leaves it largely buried. The stem carries 13 to 27 broad, hard ribs lined with stout, flattened, grey spines up to 3 inches (7.5 cm) long, the central spine curving downward. In spring, funnel-shaped flowers 1.5-2.5 inches (4-6 cm) wide open near the crown, salmon-pink to coral with paler margins. These are followed by fleshy red fruit about 1-2 inches (2.5-5 cm) long that split to expose black seeds. Growth is slow, and decades may pass before a plant reaches full size. The genus is sometimes merged into Echinocactus spp.. The low, ground-hugging body and rigid spines make the plant a hazard to livestock, the source of its common name.
Native Range
Native to southern Texas and southern New Mexico in the United States and the Chihuahuan Desert of northern Mexico, on limestone soils of desert grassland and scrub.Suggested Uses
Grown in cactus and succulent collections, rock and gravel gardens, and xeriscape plantings in hot, dry regions. The half-buried form and spring flowers suit desert-themed beds. It is also kept as a container specimen where winters are wet.How to Identify
Appearance
Size & Dimensions
Height2" - 6"
Width/Spread4" - 1'
Colors
Bloom Information
Flowering occurs in spring, mainly March to May, triggered by warmth and soil moisture after winter. The funnel-shaped, salmon-pink flowers open near the top of the stem over a period of two to four weeks. Red fruit follows in early summer.
Detailed Descriptions
Flower Description
Salmon-pink to coralFoliage Description
Grey-green stemGrowing Conditions
Sun Requirements
Requires 6-12 hours of direct sunlight daily
• Full Sun: 6+ hours of direct sunlight
• Partial Shade: 3-6 hours of direct sunlight
• Full Shade: Less than 3 hours of direct sunlight
Care & Maintenance
Care Guide
Homalocephala spp. grows in full sun on sharp-draining, gritty, limestone-based soils and tolerates intense heat and prolonged drought. It needs a very free-draining mix, as standing moisture around the half-buried stem causes rot. Water is given sparingly in the warm months and withheld in winter, when the plant rests. It withstands cold to about USDA zone 7 if kept dry, but combined cold and wet are damaging. Growth is slow, and feeding is light and infrequent. In containers a deep pot suits the long taproot.Pruning
No routine pruning is needed. Damaged or rotted tissue can be cut back to firm green flesh with a clean blade and the wound left to callus in dry air. Spent fruit and old flower remains can be removed by hand.Container Growing
✓ Suitable for container growing
Minimum container size: 3 gallons