Care of San Pedro Cactus


The scientific name of the San Pedro cactus is Echinopsis pachanoi. You are likely to see this plant retailed as Trichocereus pachanoi or Cereus pachanoi. San Pedro is a multi-stemmed columnar variety of cactus that can grow as tall as 20 feet with a spread of 6 feet or more. This undemanding plant is frost-tolerant only in USDA Zones 8b through 10 and hardy to 15 degrees F. Healthy, mature specimens produce showy, fragrant, white night-blooming flowers in early July.

Step 1

Create a potting mix for your San Pedro cactus by combining 2 parts each loam or potting soil, coarse sand and peat moss with 1 part fine gravel. Plant the cactus in a clay pot at the same depth that it occupied in the growing container. Clay is the best material for growing cacti since it provides better drainage than other types of containers do.

Step 2

Set the plant in the sink and water it slowly and thoroughly until you see liquid draining from the holes in the pot. Allow it to drain completely. Check the drip tray 24 hours later for the presence of residual draining water and empty it. The pot shouldn't be allowed to rest in water. Don't water again until the soil is completely dry.

Step 3

Place your cactus in the sunniest spot in your home. If sunlight isn't available, keep it in the best-lit spot you can provide. Outdoor specimens that have been nursery-grown typically perform best when situated where they'll receive about 25 percent shade each day. Try to replicate the lighting conditions that this cactus was grown with if you keep it outside. If it wasn't raised in full direct sun, then don't expect it to thrive in brutal heat without some shade.

Step 4

Keep your San Pedro cactus warm. This native of Peru and Ecuador likes heat and performs best at sustained temperatures well above 50 degrees F throughout the growing season.

Step 5

Feed your San Pedro cactus an all-purpose cactus fertilizer monthly during the growing season. Follow the package instructions carefully.

Step 6

Move the plant to a cooler location during the winter months, if possible. Optimum winter nighttime temperature is 48 degrees F. Continue to provide as much bright light as possible during the daytime hours.

Tips and Warnings

  • Possession of San Pedro cactus is regulated by U.S. federal laws because it contains the psychoactive chemical mescaline. It's your responsibility to know and abide by these and any other state or local laws that govern your area of residence.

Things You'll Need

  • Loam or potting soil
  • Coarse sand
  • Peat moss
  • Fine gravel
  • Clay pot
  • All-purpose cactus fertilizer


  • Desert Tropicals: San Pedro Cactus
  • University of Oklahoma: Trichocereus Pachanoi -- San Pedro Cactus
  • Lycaeum: San Pedro for the Masses
  • All Experts: San Pedro Cactus -- Sunlight Exposure
  • Lycaeum: Visionary Cactus Guide -- Legalities

Who Can Help

  • USDA Plant Hardiness Zone Map
  • Azarius: San Pedro -- Growing Instructions
Keywords: san pedro cactus, cactus care, peruvian cactus

About this Author

Axl J. Amistaadt began as a part-time amateur freelance writer in 1985, turned professional in 2005, and became a full-time writer in 2007. Amistaadt’s major focus is publishing material for GardenGuides. Areas of expertise include home gardening, horticulture, alternative and home remedies, pets, wildlife, handcrafts, cooking, and juvenile science experiments.