Growing San Pedro

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Image retrieved from on March 15th, 2014.

A tall, columnar cactus growing to 18 feet, with 6 to 8 ribs. The spines are small, sometimes non-existent. The flowers are white, reddish-brown outside, up to 10 inches long, very fragrant, night-blooming. Native to Ecuador and Peru.

Cultivation and Propagation: San Pedro may be grown outdoors in the West and South or as a pot plant in the North. It prefers a sandy, well-drained soil. If potted it should be kept in clay pot, as this will help the soil dry quickly and prevent root-rot. San Pedro is most easily propagated by cuttings. These should be dried for a few days to several weeks, until the cut surface forms a corky layer. The cutting should then be placed in a damp sand, deep enough to support it. After several weeks, when the cactus begins to show signs of growth or swelling, it may be potted in ordinary cactus soil. Sees are now becoming rare in this country. San Pedro enjoys full sunlight. Seedlings are more light-sensitive than mature plants. If they turn a reddish-brown color, place them impartial shade. Portted cacti should be turned occasionally, to expose all sides to the sun. They are also very sensitive to natural gas and should never be grown in a kitchen with a gas stove. One of the main sources of trouble with potted cacti is over-watering during the dormant months. In winter, the plants' rest period, they should only be watered enough to keep them from shriveling. In summer they may be watered often. San Pedro like most cacti, tend to grow mostly during spring and summer. During the summer they send their roots deeper into the soil. At this time rootlets may appear at the base of upper branches. This is an ideal time to take cuttings.

Harvesting: A piece of the cactus 3 inches in diameter and 3 to 6 inches long is one dose. To reduce the bulk of the cactus to be eaten, or to store it, it may be sliced thinly and dried quickly in the sun or in an oven at 150 to 225 degrees Fahrenheit. In dry weight the dose should be from 12 to 20 grams. When harvesting, always leave a stump with some areoles (spinepads) on it in the soil, as new columns will grow out of the areoles.

pp. 57-58 Growing the Hallucinogens by Hudson Grubber (1973)

San Pedro