Coryphantha compacta

Scientific Name

Coryphantha compacta (Engelm.) Britton & Rose

Synonym(s)

Cactus compactus, Coryphantha altimiranoi, Coryphantha palmeri, Mammillaria compacta

Scientific Classification

Family: Cactaceae
Subfamily: Cactoideae
Tribe: Cacteae
Genus: Coryphantha

Origin

This species is native to Mexico. It occurs in dry hills and mountains in Chihuahua and Durango, often very hard to see in the sandy soil in which it grows.

Description

Coryphantha compacta is a small cactus with a spherical, grey-green to dark green, usually solitary stem with conical tubercles tipped with a woolly areole and star-shaped clusters of appressed spines. It is very variable in spination. The stem has a slight depression at the apex and grows up to 2.4 inches (6 cm) tall and 3.2 inches (8 cm) in diameter. Tubercles are up to 0.5 inches (1.5 cm) long and arranged in about 13 spiraled rows. Each areole bears 11 to 16 stiff, white to yellow, 0.4 to 0.8 inches (1 to 2 cm) long radial spines. Central spines are usually absent, but some or all areoles occasionally bear one, initially reddish-brown, becoming yellowish with a dark brown tip, sometimes slightly hooked central spine.

Flowers are funnel-shaped with lance-shaped, pale yellow to near-white petals and appear at or near the stem apex in spring and summer. They are up to 1.2 inches (3 cm) long and 1.6 inches (4 cm) in diameter. Fruits are green, egg-shaped, up to 0.8 inches (2 cm) long, and contain tiny, brown, kidney-shaped seeds.

Etymology

The specific epithet "compacta (kom-PAK-tuh)" means "compact" and refers to the spines that often almost completely cover the stem.

How to Grow and Care for Coryphantha compacta

Light: Plant this cactus in an area of your garden that receives 4 hours of direct sunlight daily. If you are growing C. compacta indoors, place it near the brightest window in your home or office to ensure your cactus gets enough light. Place the pot on the balcony or in the garden for extra light from spring to fall if possible.

Soil: C. compacta requires a soil mix that provides root aeration and good drainage. Use a commercial cactus potting mix, or create your own.

Temperature: This cactus is heat tolerant but is not a cold-hardy plant. C. compacta can withstand temperatures as low as 25 °F (-3.9 °C). USDA Plant Hardiness Zones 9b to 11b, 25 to 50 °F (-3.9 to 10 °C).

Watering: From spring to fall, water deeply and wait for the soil to dry before watering again. Never let the pot sit in water. Suspend watering in the winter.

Fertilizing: This slow-growing cactus do not require much fertilizer to thrive but can benefit from fertilization during the growing season. Apply a water-soluble fertilizer for cacti and other succulents. Suspend feeding during the winter when the plant goes dormant.

Repotting: Repot every two or three years into a slightly larger pot. The best time to repot your C. compacta is late winter or early spring, but the repotting process can be done almost any time of the year. Ensure the soil is dry before repotting.

Propagation: Since it rarely produces offsets, C. compacta is usually propagated by seeds. Sow the seeds in late spring or summer.

See more at How to Grow and Care for Coryphantha.

Toxicity of Coryphantha compacta

C. compacta is generally considered non-toxic and is pet friendly.