Echinopsis pachanoi

Echinopsis pachanoi


Echinopsis pachanoi f. cristata (Crested San Pedro Cactus)

Echinopsis pachanoi f. cristata (Crested San Pedro Cactus) is a rare, crested form of Echinopsis pachanoi. The stem is fan-shaped, pale to…

Things to Know About the San Pedro Cactus

Now that you know how to plant and take care of a San Pedro cactus, there are some things you should know before you decide to purchase it or include it in your garden.

The first thing to know about San Pedro cacti is that they grow fast and tall. Each separate stem of the cactus can grow to be six inches wide and ten to twenty feet tall. When properly taken care of, they can grow up to a foot tall within six months and continue growing by a foot per year.

They grow especially fast and fragrant around the summertime, sprouting white flowers that bloom at night and open the following day. Because of their fast growth spurts, you’ll want to make sure that the cactus isn’t directly below anything that will stunt its growth if it’s inside. If you’re growing it outside, then just keeping it groomed and neat should be all that’s necessary.

The challenge for caring for a San Pedro cactus comes in when it gets an infection or an infestation. The most common causes of this include:

  • Etiolation
  • Desiccation
  • Overwatering
  • Sun Burn
  • Bugs
  • Frost Damage

Causes and Cures for Etiolation Growth

Etiolation is the condition of cacti growing a pale and sickly-looking growth on top of them or on their sides due to insufficient light exposure. You could say it’s the acne of the cactus plant. The growths usually look very light green or a yellow-greenish color and have a puffy shape. They are very flimsy.

To treat this condition, you need to put your cactus into stronger light as soon as possible. You unfortunately can’t get rid of the etiolation growth, it’s permanently stuck onto the cactus. But you can help the cactus get into better condition once you place it under more light more often.

How to Avoid Desiccation Rot

Desiccation is essentially what happens when a cactus gets too dry. It shrivels up and looks like a deflated beach ball with sharp spines. Even though cacti are desert plants, they can dry up faster if the weather is hotter and they don’t get enough water. While the seemingly obvious solution is to give your cactus a bunch of water at once, this actually isn’t the best option. The better option is to give your cactus a little bit of water at first and slowly progress the amount of water. Fixing the problem with this approach will help the roots grow and adapt to taking on more water, hydrating the cactus more effectively.

What Happens When You Overwater Your Cactus

Overwatering is exactly as it sounds, it’s when you give your cactus too much water and it creates a hotbed for bacteria and diseases to fester and grow. You can tell that your cactus is overwatered when it swells up to almost double its original size. The cactus stem will also usually become so saturated with water that it splits open in one or multiple places. The most harmful side effect of overwatering is that the cactus will start to rot.

A rotting cactus will usually appear brown and feel mushy to the touch. To avoid this problem, make sure that you water your cactus in intervals rather than all at once, and keep the amount of water consistent. If this does happen, stop watering the cactus for a little while. It would also be a good idea to get it out of the overwatered pot and into a fresher, drier pot. The split parts are permanent and can’t be fixed, but that won’t prohibit the cactus from being saved and to continue to grow.

The Effects of Sunburn Damage

Sunburn occurs when a cactus has been too overexposed to direct sunlight. It makes the cacti look whitish around the top or on their ridges, and more severe burns make the cactus take on a dark brown look. To treat a cactus with a sunburn, get it to a shady place as soon as possible. If the cactus is already burned to a brown crisp, then the damage is irreversible. To prevent it from happening in the first place, give it full sun exposure for a short amount of time daily, increasing the length of time in the direct sun slowly over the course of a few weeks.

Bug Infestations and How They Harm Your Cactus

Bug infestations can range from barely visible to bluntly obvious. To check your cactus for bugs, digging around in the soil a bit with a trowel or just taking a good look at it can give you a pretty good idea if there are bugs on the cactus or not. To treat bugs, you will have to physically remove as many bugs as possible from the cactus with a fingernail or some tweezers. If the infestation is of a larger scale, physically removing the plant and washing out the pot is the better option. To prevent any infestations in the future, regularly spraying the pot and the cactus with a light layer of pesticide can prevent an infestation.

Frost Damage from Cold Temperatures

Finally, frost damage is what occurs when plant cells that are exposed to freezing temperatures start dying, and the health of the cactus suffers as a result. This also causes the cells to rupture and the water doesn’t hold as well, drying it out. Your cactus is instantly more susceptible to this condition if you live in an area with colder temperatures. To prevent this from happening, bringing the cacti inside or covering them with a tarp can prevent the cold from directly affecting them too harshly. If the temperatures are lower, then a grow light can be a good option to look into.

Echinopsis Species, Achuma, Aguacolla, Saint Peter Cactus, San Pedro Cactus

Family: Cactaceae (kak-TAY-see-ee) (Info)
Genus: Echinopsis (ek-in-OP-sis) (Info)
Species: pachanoi (puh-KAH-no-ee) (Info)
Synonym:Trichocereus pachanoi
Synonym:Cereus pachanoi


Water Requirements:

Drought-tolerant suitable for xeriscaping

Average Water Needs Water regularly do not overwater

Sun Exposure:


Foliage Color:




USDA Zone 8b: to -9.4 °C (15 °F)

USDA Zone 9a: to -6.6 °C (20 °F)

USDA Zone 9b: to -3.8 °C (25 °F)

USDA Zone 10a: to -1.1 °C (30 °F)

USDA Zone 10b: to 1.7 °C (35 °F)

Where to Grow:

Can be grown as an annual

Suitable for growing in containers


All parts of plant are poisonous if ingested

Plant has spines or sharp edges use extreme caution when handling

Bloom Color:

Bloom Characteristics:

Bloom Size:

Bloom Time:

Other details:

Soil pH requirements:

Patent Information:

Propagation Methods:

Allow cut surface to callous over before planting

From seed direct sow outdoors in fall

Seed Collecting:

Remove fleshy coating on seeds before storing

Allow unblemished fruit to ripen clean and dry seeds

Properly cleaned, seed can be successfully stored


This plant is said to grow outdoors in the following regions:

Capistrano Beach, California

Huntington Beach, California

Mckinleyville, California(2 reports)

New Orleans, Louisiana(2 reports)

Gardeners' Notes:

On Mar 21, 2015, debylutz from San Diego, CA (Zone 10a) wrote:

I bought a 1 gallon pot with two cuttings at Home Depot about a year ago. I repotted each cutting into its own 1 gallon pot. Presently, each cutting is over 30 inches tall with 1 to 2 offshoots. I love this cactus! It has very small spines. I plan to use it in a Mexican-style landscape.

On Dec 2, 2013, martenfisher from Crystal River, FL wrote:

Would be nice to see less information about these being psychoactive. We get the point already. I want to see more cultivars being produced for bloom yield than mescaline yield. This wonderful plant is a great beginner cactus and landscape plant. I think most plants are lost from rich soil and over fertilizing creating a more tender sensitive plant. It needs the alkaloids for defense and plants that are soft and babied will rot or fall over. I find these at lowes and Home Depot every spring or summer.

On Mar 29, 2011, succulentlab from Fresno, CA wrote:

I absolutely love this plant! This is the species of cactus that first got me into succulents. Grows extremely well in central valley CA. I have one specimen that grew over 24" in a single season. WOW!

On Sep 3, 2009, MelisandeLuna from Birmingham, AL wrote:

I've been growing these for years out in Bakersfield, California. I dragged one to New Orleans with me and left most of it at a friend's house, I took a piece with me to Alabama, but the cold killed it (sub zero). I just recently bought one from a vendor in California, I think I'll have to bring it inside to over-winter so I don't lose it again.

On Aug 2, 2009, homerplant from Lecompton, KS wrote:

People don't realize how cool and amazing this plant really is. If a piece were to break off and fall under cover or just can't find light for some reason. It will send a little, skinny, usually white in color, piece to find the sun. Once the sun is found. That is where it starts to green up and become plump.
I have to put them away for the winter here in Kansas. 5 months later, I open up the box and they will still grow and search. No water no light. In the spring if the white shoot is too long and can't support itself. I cut it off. You can cut any Pachanoi and it will grow pups. As long as you have 3 - 6 inches they will grow. Let the half that will be put back in the ground to callus over before planting. This takes 3 or 4 days depending on the humidity. The part that is sti. read more ll in the ground will be the pup producer. Try to cut at a slight angle so rain water will not puddle. Before long you will have a forest. The only way to really kill a Pachanoi is over caring for it. Just let it get full light. A skinny Pedro is not getting enough light. Note: Black spots are not bad unless it becomes soft and mushy. Cut that out IMMEDIATELY! That will spread and ruin a plant if not taken care of. The scar will sometime produce pups. See, it is always trying to make it. No matter what gets thrown its way.
Try laying one on its side. Then watch the pups. Have fun.

On Jul 3, 2008, superpepper from Lauderhill, FL (Zone 10a) wrote:

I found this cactus abandoned and took it home. In the 3 or so months I have had it, it has grown several inches and developed several flower buds. Probably one of the easiest and most attractive cactus I have grown.

On Oct 10, 2006, promethean_spar from Union City, CA wrote:

When I bought my house in Fremont, CA, one of these was abandoned out front in a 3g pot. I just left it where it was and watered it during the summer and it grew about a foot and added a new arm from the base. It appears to have flower buds right now, unfortunately they're supposed to be self-sterile so I doubt I'll get seed.

I got seed for a few other hardy species of it's genus and hopefully will have a row of tall cacti in a few years.

On Nov 16, 2005, slimmy from Lisboa,
Portugal wrote:

I'm growing this cactus for about 2 months from seeds, and I think that they are doing fine. It's almost winter here in Portugal, lots of rain and pretty cold, but they look like tiny candies, fat, bright and succulent. I'm enjoying it. regards

On Mar 26, 2005, Hekate from Austin, TX (Zone 8b) wrote:

This is the only cactus I own and so far I rather like it. In the spring it will put out a bud which will become another long cactus spike. They get very tall and heavy so it's important to make sure the plant doesn't go through a stressed period that will create weak parts which will cause toppling later on. I have never seen mine flower, but that is likely due to my own inexperience.

On Jan 23, 2005, Xenomorf from Phoenix, AZ (Zone 9b) wrote:

Flowers are white, fragrant and nocturnal (another night blooming cereus).
The people of Tarahumara and Seri of Mexico have long used this plant for medicinal purposes, one being, the essence is applied to the scalp to prevent baldness.

On Dec 30, 2004, rh3708 from Westmoreland, TN (Zone 7a) wrote:

It is a fast growing cactus I have it growing in a large pot of Peace lily's.
I would like to set it out in the yard but haven't found just the right spot yet.

On Jun 21, 2004, tyler70006 from New Orleans, LA wrote:

This is the easiest and fastest growing cactus I've owned. Grows about a foot a season and will tolerate a lot of rain without rot. We have very hot summers in New Orleans and this cactus loves the heat. Will die and become a cactus shaped ice cube in a freeze. I use ordinary potting soil and fertilizer.

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.

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.

  • The scientific name of the San Pedro cactus is Echinopsis pachanoi.
  • 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.

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.

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.

  • Set the plant in the sink and water it slowly and thoroughly until you see liquid draining from the holes in the pot.
  • If it wasn’t raised in full direct sun, then don’t expect it to thrive in brutal heat without some shade.

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.

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

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.

Echinopsis pachanoi

Trichocereus pachanoi Britton & Rose

Echinopsis pachanoi (syn. Trichocereus pachanoi) — known as San Pedro cactus — is a fast-growing columnar cactus native to the Andes Mountains at 2,000–3,000 m (6,600–9,800 ft) in altitude. [1] [2] It is found in Argentina, Bolivia, Chile, Ecuador and Peru, [3] and it is cultivated in other parts of the world. Uses for it include traditional medicine and traditional veterinary medicine, and it is widely grown as an ornamental cactus. It has been used for healing and religious divination in the Andes Mountains region for over 3,000 years. [4] It is sometimes confused with its close relative Echinopsis peruviana (Peruvian torch cactus).

Watch the video: How to identify the PC Pachanoi Pachanot.. and is it really a San Pedro cactus?