Hedgehog Cactus Echinocereus engelmannii, Cactus family ( Cactaceae ), Hedgehog Cactus. Also called Strawberry Hedgehog Cactus. The more common strawberry hedgehog has bright pink flowers in spring, but some varieties have different colors, from purple to lavender. The flowers are up to 3 inches in diameter, 2 to 3.2 inches long. The flowers close at night and reopen in the morning Growth Habits: Clumping columnar cactus, mostly erect light green stems, 4 to 12 inches tall (10-30 cm), 2 to 4 inches diameter (5-10 cm), branching freely from the base; 11 to 14 low obtuse ribs; 4 to 6 yellow or brownish central spines, 2 to 3 inches long (5-7 cm); 10 to 13 radials, 0.4 inch long (1 cm).