Carnegia

Family. Cactaceae.

Origin. Arizona, Northern Mexico. 

Description. Carnegia is a large, tree-like, erect cactus, reaching a height of 15 m, a trunk with a diameter of up to 70 cm. The main trunk has 8 - 12 side branches, formed at the base of large plants at least 4 m high. The ribs are straight, areoles densely arranged, white-gray. The spines are thick, up to 4 cm long, golden brown to gray in color. The flowers appear at the top of the stem, white with a yellow center, very showy, bell-shaped, up to 7 cm in diameter, fragrant. Each flower remains open for 1 - 2 days, but they open sequentially and the flowering period can last up to several weeks. The fruits are oblong, green, turn red when ripe, up to 4.5 cm in diameter and up to 7 - 8 cm in length. The root system is taproot, goes into the ground to a depth of 1 m.

Height. In its natural environment it reaches a height of 15 m, but the growth rate is only about 30 cm per year under good maintenance conditions.

Temperature conditions

In spring and summer, the ideal temperature is 20–25 °C. During the dormant period, this cactus is placed in a cool place – about 10 °C. Adult specimens can tolerate short-term frosts if they are in dry soil.

Reproduction

Propagated by stem cuttings rooted in spring. The cut site should be dried for 3-4 days. Water moderately after transplanting. Seeds are sown in spring in well-drained soil. Germination time is 2-4 weeks if the pot with seedlings is placed in a warm place with a temperature of 22-24 °C.

Lighting

Carnegia domestica should be provided with the maximum amount of sunlight in the morning and evening, as well as throughout the day in autumn and winter.

Flowering time

Large buds appear in late spring. Flowering occurs only in large adult plants at the age of about 30 years.

Soil

The soil should easily pass water and air, pH not higher than 6.5. A mixture of leaf humus, turf soil with a large amount of coarse river sand or perlite to improve drainage and small pieces of charcoal is suitable. You can use a ready-made substrate for cacti and succulents. 

Feeding

Feed monthly with fertilizers for cacti and succulents high in potassium, calcium and phosphorus. The fertilizer is diluted to half the recommended dose and applied in spring and summer. During the dormant period, cacti are not fed.

Purpose

Over time, the carnegia reaches impressive sizes, so collections mainly contain young specimens.

Air humidity

Does not require spraying. During the fall and winter, keep the cactus in a dry atmosphere and provide it with sufficient air movement without cold drafts. 

Watering

Water in spring and summer until the earthen ball is completely soaked; be sure to remove excess water that has accumulated in the pan after watering. The soil should be dried between waterings. In the autumn-winter period, water extremely carefully - only to avoid drying out the earthen clod.

Transfer

Carnegia has a fairly large root system and should be replanted as it grows in the spring, once every 1 - 2 years into a larger pot. 

Pests and diseases

When water stagnates and is over-moistened, especially in the autumn-winter period, rot occurs. 

Of the pests, the main dangers for the cactus are mealybugs, spider mites and scale insects.