Publication: Field number KK102 El Molle.
Description
The name Copiapoa imbricata supplied under an unpublished name by the cactus merchant Karel Knize (KK102) can be referred to forms within the variability of Copiapoa coquimbana this species shows great variation and it is sometimes difficult to separate one local form from another. It distinguishes for its strong, chocolate-brown to almost black young spines.
Origin and Habitat
Chile, El Molle, Rio Elavi and adjacent areas.
Altitude: 50-700 metres above sea level.
Cultivation and Propagation
Considering that Copiapoa coquimbana var. imbricata comes from a habitat with an extremely arid climate, they are remarkably tolerant of pot culture. These plants have taproots and are susceptible to overwatering. They requires also an appropriate air circulation. Copiapoas are summer grower species easy to cultivate.
Growth rate: This is a slow growing cactus kept for the beauty of its form that will make clumps given the best conditions.
Soils: It likes very coarse mineral cactus mix soil, but can become too elongated if compost is too rich.
Repotting: Use pot with good drainage.
Watering: It requires light but regular waterings in summer, but let the soil mix dry between waterings, but do not overwater (Rot prone), it must be strictly kept dry throughout the winter quiescent period since it is very sensitive to any moisture excesses keep dry in winter.
Fertilization: Feed with a high potassium fertilizer in summer.
Hardiness: Not highly tolerant of a great deal of frost. They need to be kept in a cool place during winter rest and are resistant to light frost if kept on the dry side prior to, and during, cold weather ( they are hardy to -2 C ° C short periods). However some warmth throughout the year will increase the grower’s success (minimum 5° to 10°C during rest season).
Exposition: Requires full sun or light shade and careful watering to keep plant compact with strong coloured spines. Tends to bronze in strong light, which encourages flowering and heavy spine production. Light shadow my be useful in the hottest summer days.
Uses: It is an excellent plant for container growing. It always looks good and stays small. It look fine in a cold greenhouse and frame or outdoor in a rockery.
Pests & diseases: It may be attractive to a variety of insects, but plants in good condition should be nearly pest-free, particularly if they are grown in a mineral potting-mix, with good exposure and ventilation. Nonetheless, there are several pests to watch for:
- Red spiders: Red spiders may be effectively rubbed up by watering the infested plants from above.
- Mealy bugs: Mealy bugs occasionally develop aerial into the new growth among the wool with disfiguring results, but the worst types develop underground on the roots and are invisible except by their effects.
- Scales: Scales are rarely a problem. It is wise to treat your whole collection with a systemic insecticide twice a year in spring and autumn.
- Rot: Rot is only a minor problem with cacti if the plants are watered and “aired” correctly. If they are not, fungicides won’t help all that much. To prevent rottenness it is also advisable to surround its root neck by very rough sand or grit, this help a fast water drainage.
Propagation: Seeds (or offsets if available), Grafting is often used to speed growth rate and to create a back-up to plants in collection. Seeds germinate in 7-14 days at 21-27° C in spring, remove gradually the glass cover as soon the plants will be well rooted (ca 1-2 weeks) and keep ventilated, no full sun for young plants!
