San Pedro cactus (Echinopsis pachanoi) - live plant

• A live, rooted plant
• Sold as an ornamental and botanical collector's plant
• Packaging suited to live plants

Echinopsis pachanoi is a columnar cactus from the Andean slopes of Ecuador and Peru, between 2,000 and 3,000 metres above sea level. It forms upright, bluish-green stems, usually with six or seven well-defined ribs, and short spines, or none at all on some clones.

Its botanical name has changed: long described as Trichocereus pachanoi, it is now placed in the genus Echinopsis. Both names are still in circulation, and refer to the same plant.

Its flowering is spectacular and nocturnal: large, fragrant white flowers, 20 cm or more across, that open for one night and close again in the morning.

This is the main horticultural use of this species. Its rapid growth, its vigour and the compatibility of its cambium make it the most widely used rootstock for growing slow, fragile or chlorophyll-lacking cacti. A scion grafted onto San Pedro can reach in one season the size it would have taken years to reach on its own roots.

A very free-draining substrate, such as a cactus mix with a good proportion of mineral material. Full sun, acclimatising it gradually to avoid scorching a plant that has been in transit.

Water generously during the growing season, letting it dry out completely between waterings, and keep it dry and cool in winter. It is this winter dryness that determines flowering. It tolerates brief light frosts if it is perfectly dry, but in our damp climate it is better to bring it indoors.

Trichocereus or Echinopsis pachanoi?
The same plant. Trichocereus is the former genus name, Echinopsis the name accepted today. You will find both in the trade and in horticultural literature.

Why is it used as a rootstock?
Because it grows fast, it is robust, and its conductive tissue fuses well with that of many other cacti. It is an absolute classic of cactus grafting.

How fast does it grow?
Quickly for a cactus: several tens of centimetres a year in good conditions, which is exceptional in this family.

Can it withstand frost?
It tolerates brief light frosts provided it is completely dry. In France, winter damp is more deadly to it than cold: give it shelter.

This plant is sold exclusively as an ornamental and botanical collector's plant. Also worth exploring: our rare plants and our folklore plants.