Have a comment?

ANSWER
I don't know of any issues with rocks, or pebbles in the bottom. But I don't do it.

Collectors sprinkle crushed rocks on the surface to act as a mulch, hold down the soil from sloshing during watering and to look nice. It does look nice; I used to obsess to obtain bean size chunks of feldspar, granite, or red rock.

But rock mulches are not needed for these cactus. San Pedro wants to become a tree!

So I concentrate more on re-potting every year with fresh soil in a bigger pot up to 20 gallon. Those produce so much growth I harvest cuttings from them like a farm crop.

Pebbles on the bottom are fine, many people do that for house plants. But the real concern is that there be side slot holes - like nursery pots have. That allows water to exit the bottom side. Bottom only holes can allow standing, stagnant water if the pot is in a pan.

Extreme cases of no drainage
A person once sent me photos of rotting San Pedro left outside in Florida. He used those molded Styrofoam pots that look like terra cotta. They sell them at Home Depot and they do not have any drainage holes at all! I did the same thing -- my helpers filled some huge containers from Home Depot that didn't have drainage holes. I was moving a 100 pound San Pedro stump. It died with rot before I discovered there were no holes on the bottom.

Back in 2004 I had to move my entire collection, so I used those blue 20 gallon tubs from Walmart (they used to be $5) I drilled several 3/4" holes around the bottom sides - to ensure full drainage. The bottoms were drilled with about a dozen 1/2" holes. The side bottom holes assure positive, visible drainage. Now I buy nursery pots in 10 and 20 gallon size used for trees/shrubs. They have nice large slot holes on the side around the base. Rocks in the pot are perfectly OK. Kate used to use crushed rock instead of perlite. She used the rock mix in clay pots with rare cactus that never grow very large. But 50% perlite makes a lot of sense when you fill a 20 gallon container because 50% - 10 gallons - of rock would make it very heavy to move. Either rocks or perlite provide good drainage.

My perlite mix, potted San Pedro drain so well that my best specimens grow outside. They get drenched by the winter rains - pure sweet water that rids the soil of built up salts. Very few develop rot. More and more of my large ones are being placed outside to let the winter rain clean the soil of salts and left over fertilizer.

I have specimens in the earth, too. Gophers go for them, so that is another story. Large containers work great is what I have discovered. Some are under stretched 30% shade cloth, others are placed where there is not shade net, but where they receive full sun 1/2 the day, shade the rest.

I don't use pebbles or crushed rock.

I germinated thousands of these Wild Andes Peruvian torches a few years ago. One repeat customer like you asked me to select as varied ones (wild andes) as possible when he figured out how much genetic diversity they express. You are the second person to notice this. [More photos] This same broadness of variation (spines, fatness, skin color) shows in the larger Peruvian torches I sell -those are from Karel Knize seed shipped directly from Peru.  Only Bridgesii, KK242, San Pedro and a few others are boringly similar because they have been propagated from cuttings for decades.

The genetic differences in apples
Apples have so much genetic diversity that commercial farmers don't use apple seeds. They graft cuttings from the specific variety they want. For example if you germinate the seeds from a golden delicious apple it will most likely produce a small sour apple. Most apples grown from seed turn out to be sour - and historically used for making cider, not eating.

Biologist traced apples back to their origin in central Asia. Here is an edited explanation (will make you roll your eyes):

[http://en.wikipedia.org/wiki/Apple] There are more than 7,500 known cultivars of apples resulting in a range of desired characteristics. Cultivars vary in their yield and the ultimate size of the tree, even when grown on the same rootstock. In the wild, apples grow quite readily from seeds. However, like most perennial fruits, apples are ordinarily propagated asexually by grafting. This is because seedling apples are an example of "Extreme heterozygotes", in that rather than inheriting DNA from their parents to create a new apple with those characteristics, they are instead different from their parents, sometimes radically. Triploids have an additional reproductive barrier in that the 3 sets of chromosomes cannot be divided evenly during meiosis yielding unequal segregation of the chromosomes (aneuploids). Even in the very unusual case when a triploid plant can produce a seed (apples are an example), it happens infrequently, and seedlings rarely survive. Most new apple cultivars originate as seedlings, which either arise by chance or are bred by deliberately crossing cultivars with promising characteristics.

OK, so I am saying that maybe these Peruvian sacred cactus seeds are also unpredictable. There is no commercial interest in sacred cactus so no one is spending millions of dollars to research their genetics. We can assume that people valued trichocereus for thousands of years, propagated them by cuttings based on the particular traits they liked. They fall over naturally and self root; any fool can figure that out and did for thousands of years. Growing them from seed is almost unnatural. In 20+ years I have never encountered San Pedro spontaneously growing from seed.

Right now (winter) my cactus are dormant (it is winter) and I have thousands of Peruvian seedlings to pot up from 2", 4", and even 6". I have spent years patiently tending these KK seeds. In 2010 that effort will pay off as their growth rate rockets.

Many of the wild Andes seedlings were too weak, many too light sensitive, etc. I've lost over a thousand weaklings. But that leaves thousands more that are vigorous. Some are fat, others tall and thin. Spine variations is fascinating --just as you observe.

My Karel Knize seedlings (started in 2006) and the wild Andes (2007) will be my most interesting specimens ever offered for sale. I have to keep some for private stock (take cuttings), but now have more and more of them to share with other collectors.

I can't name these variations -there is no official study of what is growing in remote parts of the Andes. But I can group the plants by appearances (spines, column shape, skin color, etc.) and photograph each population as a "look similar" variety for sale.

A small number of my seed grown San Pedro from Knize are now 12" to 16" and must be saved for propagation by cuttings. These are the only San Pedro I own that were raised from Peruvian seed. They are lovely - fat, dark green, glossy, with short spines.

This stuff is a lot of fun if one is patient. It takes years to produce mature specimens. Sacred Cactus are as sweet as kittens with just as many different faces. They have lived for thousands of years in remote Peruvian mountain valleys before making their way to my farm in California and to your house via FedEx Ground! It is a great honor for me to host their existence. Boy, when I die someone is going to have a fun time with the cactus orchard I have created.

The literature says alcohol but is that methyl, ethyl, or isopropyl? Usually they mean ethyl when not specified if I remember correctly. I use iso because I hate methyl and ran out of ethyl. Used to have reagent grade ethyl but that is expensive...and iso is on hand. I just store the brush as is. It gets nasty. Why save the brush? I use a basting brush from the grocery store and each season buy a new one. 2" paint brushes are also inexpensive.

Clonex can be overkill. It is an option but is not essential. Root buds can figuratively explode out like maggots from a corpse. I rooted San Pedro for 18 years without clonex. It is used simply to speed things up - to produce plants with good root systems earlier in the year (so I can sell them sooner).

CLONEX ON DRY OR FRESH?
I've done both. Doesn't seem to matter. You can put it on fresh ones, or dry ones when you put the cutting in dry (not wet) potting soil. On fresh cut tips it dries with the cut end.  I plant cuttings loosely in the soil to allow air circulation. I no longer tamp the soil down around a cutting as that can cause anerobic stuff to grow. Damp soil packed tightly around a cutting increases the incidence of rot.
 

So just set in dry soil loosely. Go at least 4 to 5 inched deep as that seems to helps with support and rooting. Mist the cuttings with water in the evening during hot times of year, even before roots form -- the mist lays droplets on the skin the plant will suck in when it opens its stoma at night. That is my understanding.

Don't waste your time with tiny cuttings. God am I sick of email asking how small a cutting can you root? Can I slice this up into 10 pieces? THE BIGGER THE CUTTING THE FASTER IT TAKES OFF GROWING! Below a certain size they can barely muster up enough energy to root and photosynthesize worth a damn. Yet many arm chair geniuses do not understand "The whole is greater than the sum of the parts." Trust me - a large cutting chopped into slices is like expecting the linear addition of pieces to exceed the exponential growth of the whole.

I just do this once a year in spring. Well, then again in fall at harvest time for cuttings that are too skinny to sell. Oh, ebay people would love to purchase them but they fall below my size standards. Those get "winter rooted". If I leave them on a shelf they will go phototropic and develop yellow tips. Instead put them in dry potting soil under 2 layers of 30% shade cloth, in an unheated greenhouse. Believe it or not they just stand still looking exactly like the day they were picked -- September ones look right now in January like live plants. But they are simply waiting for spring - they will not root in wither.
http://sanpedrocactus1.com/winter_rooting.htm

SEASON IS THE KEY! Size matters!
Cactus go winter dormant, then they wake up in spring. Go with the seasons and they will root just fine. Has to be spring, early summer, warm soil. Take the largest cutting you can for the best results. Cuttings weighing 10 or 20 pounds can become very impressive specimens in just 12 months. Have fun!