Opuntia santa-rita is often listed as a synonym of Opuntia gosseliniana, but it is a larger plant with thinner stem segments. It is also commonly confused with Opuntia macrocentra, which has yellow flowers with a bright red center. Moreover, there are natural hybrids between Opuntia santa-rita and Opuntia chlorotica, which adds to the complexity of identifying this plant.
Scientific Name
Opuntia santa-rita (Griffiths & Hare) Rose
Common Name(s)
Purple Prickly Pear, Santa Rita Prickly Pear
Synonym(s)
Opuntia chlorotica var. santa-rita, Opuntia gosseliniana var. santa-rita, Opuntia macrocentra var. santa-rita, Opuntia violacea var. santa-rita
Scientific Classification
Family: Cactaceae
Subfamily: Opuntioideae
Tribe: Opuntieae
Genus: Opuntia
Etymology
The specific epithet "santa-rita (SAN-ta REE-ta)" refers to the Santa Rita Mountains in Arizona, United States, probably the type locality of this cactus.
Origin
The native range of Opuntia santa-rita is from Arizona, New Mexico, and Texas in the United States south into northern Mexico.
Description
Opuntia santa-rita is a shrubby or tree-like cactus with a short trunk and branches of gray-green to bluish-green segments that turn lavender to red-purple under stress. It can grow up to 6.6 feet (2 m) tall. The stem segments are flat, usually subcircular, sometimes ovate or obovate, and can reach up to 8 inches (20 cm) in diameter. They are often spinless or typically have few spines along the margins. The spines are straight to slightly curved, pale yellow to horn-colored, aging reddish-brown, and up to 1.6 inches (4 cm) long. The areoles also bear a tuft of yellow to tan glochids that age to brown.
In late spring and early summer, this plant produces yellow flowers reaching up to 3.6 inches (9 cm) in diameter. The spineless fruits are purplish, green inside, and contain tan seeds. They are egg-shaped and depressed at the apex, reaching up to 1.8 inches (4.5 cm) in length and 1.2 inches (3 cm) in diameter.
How to Grow and Care for Opuntia santa-rita
Light: Opuntia santa-rita thrives in full sun, but some shade during midday and afternoon can prevent sunburn in hot climates. A window that receives sunlight 6 hours a day works best when grown indoors.
Soil: This cactus requires a soil mix that drains well. So, use a commercial cactus potting mix or create your own.
Temperature: Extremely tolerant of high temperatures, Opuntia santa-rita prefers cooler temperatures in winter. It grows best in USDA Plant Hardiness Zones 8a to 10b, with average minimum winter temperatures ranging from 10 to 40 °F (-12.2 to 4.4 °C).
Watering: From spring to fall, water moderately and let the soil dry out completely before watering again. In most areas, rainfall will be enough for established plants. If potted, never let the container sit in water. During the winter, suspend the watering.
Fertilizing: Opuntia santa-rita does not need fertilizer when planted in the ground. However, in a container, the plant will benefit from fertilization during the growing season. Apply a water-soluble fertilizer. Suspend feeding during the winter when the plant goes dormant.
Repotting: Repot only when the cactus becomes potbound or is too large and unstable in its container. Choose a slightly larger container with drainage holes at the bottom. The best time for repotting is late winter or early spring.
Propagation: You can propagate Opuntia santa-rita by stem segments or seeds. Using stem segments is the easiest method and yields faster results. For best results, take stem segments in early summer. Sow the seeds in late spring.
Learn more at How to Grow and Care for Opuntia.
Toxicity of Opuntia santa-rita
Opuntia santa-rita is not toxic to humans or pets. However, keep the plant away from pets and children as it has harmful spines and glochids that may cause skin irritation.
Links
- Back to genus Opuntia
- Succupedia: Browse succulents by Scientific Name, Common Name, Genus, Family, USDA Hardiness Zone, Origin, or cacti by Genus
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