My Rooting "tek"

Nan's Nook : Archives : Botanicals : Cactus : San Pedro : Growing San Pedro : Rooting San Pedro
Posted by: ion Jun 04 03, 04:48 AM GMT
Rooting Soil Formula

1.5 cups dry, already un-bricked Coir

2 cups Desert sand
* this is almost a 40/60 mix, coir to sand

1.5 teaspoons Bone meal (1-11-0)

A bag of potting charcoal

you may also need .5 teaspoon of hydrated horticultural lime.

Mix coir, sand, and bone meal together. Gently rake fingers across the surface to collect a couple large bundles of "coconut hair" every once in a while. They can probably be left in, but they annoy me...
Anyway, moisten the mix with:

1/2 strength Cactus Juice (1-7-6 +1 Ca) in distilled water.
(Cactus Juice is made by Farnham Companies, Inc. It used to be Sudbury. It is a fertilizer specifically designed for cactus in its NPK ratio and Calcium content. Other than that, it's kinda crappy... no micronutrients, it contains too much chlorine in my opinion, and it is sold weak because it is a cactus fert! The directions indicate 1 capful per gallon, but I used 1/2 capful in almost a gallon.)

Mix for a while, and continue to add fert water in little splashes until the entire mass is uniformly damp. Coir takes a little while to soak up the water, so mix well before adding more. Once the stuff just barely clumps in a tight fist before falling apart, it's at the right moisture level.

The pH of this mix was 6.9, so I added half a teaspoon of hydrated horticultural lime. This brought the pH up to 7.9, which is near perfect. You can measure the pH, yourself, or you can just go with the formula and add the lime.

Get a shallow pan for holding the soil. You only want the cactus to sit on top of the soil (maybe sink about an inch or so for stabilizing) for rooting. BTW, I just made this up as I did it, and I happened to make the exact amount needed for an 8.5 diameter by 1.25 inch deep tapered pie pan. It was from a Mrs. Smith's Apple pie... mmm. drool.gif I just tried to figure this out mathematically, and it is so wrong... oh, well.

Put about 1/4 inch of potting charcoal in the bottom of your dish. This will absorb any metabolites produced by the eventual microbes in the soil. It helps the cactus out in a non-draining pot like this.

Put the mix and the charcoal pan in the oven... leave them separate... you may need to mix more water in after baking.

Bake this stuff for 15 minutes at 225 F (this brings the soil temp up to 165 F), then lower the oven temp to about 160 (just estimate) for another 25 minutes. Turn the oven off and let the two things cool in it for a bit.

When you're ready, wash your hands and take the stuff out of the oven. Add more of your fert water if necessary. I needed precisely 1 bloop. tongue.gif

Scoop the soil out of your baking dish (I use a rusty steel pan... Iron oxide brings good luck with plant dirt biggrin.gif ), and into the shallow pan. Pack it down evenly over the layer of charcoal. When the pan is full, pack it tight with a flat palm.

Set the cactus on top of the stuff or sink it a bit (I had to sink the crest for balance).

You can use bottom heat or not. I probably won't because it's a pain in the butt. If you do, set it for 70 degrees and make sure it doesn't get hot during the daytime sun.

Spray the soil with tepid water whenever it looks or feels too dry... probably about 2 days or so.

Now that I posted this, I think I already talked about it, before... ohmy.gif


Posted by: Voodoo Jun 07 03, 04:18 PM GMT

Im having trouble getting a couple of cuttings to root. Would it be worth it to transfer them over to the rooting soil you described? Im not sure what the problem is with them, and Im beginning to worry. Thanks for the help.

Posted by: ion Jun 08 03, 02:13 AM GMT
Yes. Clean them up (Use a soft toothbrush and a dab of dish soap) and transfer them. This method provides a more controlled environment, so things like rot, weather, and insects are more easily avoided. wink.gif

Like I said... this is for "the precious ones". wub.gif


If you wish to "bottom water" to encourage roots:

Moisten the soil slightly. Cut a drinking straw in half and push a piece straight down into the soil until you feel the "crunch" of the charcoal. Do this about 2 or 3 inches from your cactus. Pull it up and tap out the "soil plug". You should have a perfect hole in the soil, now. Check to make sure that you did not make the hole go all the way to the bottom of the pan... only down to the top of the charcoal layer. Clean the straw well (use iso and let dry, if you wish) and re-insert it into the hole. Pack the soil around it to stabilize it. Repeat this procedure on the other side of the pan/cactus.

Make sure the cactus pan is on a level surface... use a level, it's important. wink.gif Use a clean syringe to squirt about 10 ccs of water into each straw (double the amount for double the recipe of soil, etc.), about once or twice a week (unheated pan).

You can cover the end of the straw with a bit of plastic or something, if you think it is necessary. (i.e. you have a lot of gnats in the area)

Now you have a charcoal reservoire wicking moisture up into the soil from below. biggrin.gif

Be aware that pedros like more water than many other cacti. If you are rooting desert specimens that normally live in the open (not in niches, like lophs do), then you should water less.


Posted by: Voodoo Jun 08 03, 11:10 PM GMT
OK, Ion. One more question. I was under the impression that a person shouldnt water cuttings untill after the formation of roots. Is that incorrect?

Posted by: ion Jun 09 03, 04:42 AM GMT
That can be true, yes. However, Pedros and many other similar cacti don't seem to mind a little moisture... and it does help to keep them from dehydrating quite so badly while they form their roots.

Some folks think that bottom watering encourages the plant to shoot roots by "letting it smell the water that is just out of reach".


Posted by: Voodoo Jun 09 03, 08:46 AM GMT
Excellent. Thank you.

Posted by: ion Jun 23 03, 02:36 AM GMT
Okay! The culmination of this little experiment:

Placed the cactus in the "rooting soil" on June 3rd.

Bottom watered only twice. It appears that the surface may dry out rapidly, but the lower levels stay moist for a very long time.

The pan was indoors, under indirect light from a southern window (outside, an awning blocks a great deal of the incoming light). The soil temperature never got above 75 F, and generally remained this temp (same as the indoor air temp) for the duration.

This was an experiment, so the cactus was checked for roots more often than what is normally necessary. Checked for roots (carefully lifting the cactus, looking, and setting back in its spot, perfectly) a grand total of 3 times. The second examination revealed a tiny amount of white fuzz (some sort of benign fungus, apparently) which was gently removed with clean fingers. A small amount of contamination was expected due to the lack of sterility of the fertilizer water... no problem at all wink.gif .

Around the 10th day, 3 small (about 1" diameter by 3-4" tall), clean, well-scabbed cuttings were placed into the mix along with the large center cactus (the crested specimen). They needed a home, and cacti seem to love neighbors. wub.gif

The final check, performed exactly 20 days after putting the large cactus in the mix, revealed that the crested cactus has its first root. biggrin.gif

20 days is pretty good, I'd say. wink.gif
We'll see if the smaller ones get the same general times. think.gif


Posted by: ion Jun 23 03, 02:50 AM GMT
Oh! Almost forgot...

If you have a species that takes longer to root up, you can avoid contamination (even though it probably won't be harmful to the cactus) by using sterile water, and being very clean about the area and the checking and such.

This method made for almost zero dehydration of the plant! Only the thin "fan spreads" of the crest became ever-so-slightly softer, and the central portion lost no turgidity at all! I would expect that normal columnar cacti would experience the very same lack of dehydration, or better. The reason it didn't dehydrate is because the light was soft (not dim, per se, but just diffuse), the temp never got above 75 F, and there was less air movement than there would have been outside.

She will be potted, shortly. wub.gif


Posted by: ion Jun 23 03, 03:04 AM GMT
Hehe... I can't stop writing... tongue.gif

I recently learned a bit more about the many species of small, dumpling-like cacti. Among the things I learned was probably one of the most useful tidbits for trying to get such cacti to root...

These cacti often live almost or even completely buried in soil. ohmy.gif

You can bury a dumpling down into this mix so that just the tippy top is poking out of the mix... this will avoid dehydration even further over those long periods of time it may take for such cacti to root up. wink.gif

This may make the sides of the cactus a lighter color than the tippy top, or it may make them darker... it depends on whether the cactus is genetically inclined to respond to the lack of light (to the buried green portions) by removing chlorophyll and using the buried flesh to grow new roots (pedro does this, but it's not a dumpling)... or whether it is inclined to produce higher amounts of chlorophyll in the buried flesh to try to suck up and use as much of the small amount of light as possible.
In general, one might assume that a tug-of-war between these two tendencies would simply make the cactus flesh remain the normal color shade. tongue.gif


Posted by: ion Jun 25 03, 03:04 AM GMT
BTW, in case you need "proof" of the rooting times, I finally took some pictures.

The things are hard to photograph due to their size, though...

Posted by: ion Jun 25 03, 03:05 AM GMT
1 more:

Posted by: Driador May 12 03, 06:11 PM GMT
Hey all, I've got 3 good size San Pedro cuttings that have been in the pot for the past 2 weeks or so. Today I noticed a small splotch of yellow-brown rot up near the top. I quickly cut it out and coated the wound with flowers of sulphur, but then I started feeling the cactus for any more noticeable soft spots. While there aren't any really mushy spots, I have nopticed that the skin seems to be well...not spongy, but not really super firm like they were when I first received them. This got me to wondering about root development, so I dug one up. Nothing. No roots, no beginnings of roots, nothing. cry.gif How long does it take for these to root? The only thing wrong that I can think of is the huge amount of rain that they have gotten recently (although they do have proper drainage). Any hints fealls? I'd hate to see these babies die on me. sad.gif

Posted by: Lophophophile May 12 03, 09:51 PM GMT
yep, sounds like too much water. supplimental waterings to the rain storms many of us have had recently may have caused that rot. don't water it for about 2-3 weeks and it should have some roots by then. also, don't pull it out of the soil to check, because this can damage the root hairs. just give it a slight tug in a month and if it stays put then its got some roots.

Posted by: Driador May 12 03, 10:28 PM GMT
What about the tender tissue? Is this something I need to be concerned about, or do you think it is also due to the large amount of rain that we've had?

Posted by: ion May 13 03, 12:17 AM GMT
The softness of an unrooted cactus is due to dehydration... yes, even in this weather. Sometimes, even a specimen with roots that has been dug up and re-potted will get a little soft before the roots re-establish themselves. Nothing to worry about unless they are midsection cuttings... you probably saw my "observations" thread about that.

The way cacti are traditionally rooted is different than just putting them in the pots of soil where they will live. This works for pedro, usually, because it is an extremely hardy cactus.

Normally one would root like this:

Find a shallow clay pot, wooden box, or some other such container. It needs to be about an inch deep for every 6 inches of height on the cactus cutting. For example, if you have a 1.5 foot cutting, the pan should be about 3 inches deep.

Sterilize a 60/30/10 mix of course sand, peat (I would use coir, instead), and charcoal in the oven at about 200 degrees for an hour or so. Sterilize the pan the same way. You can even just mix the stuff, put it in the pan, and cook the whole thing.

When all is cool, spray the surface with a little potable water. Use stuff from a storebought jug, not the tap.

Find a sunny window with an electrical outlet nearby.

Put the pan there over a low-even heat source like a germination pad or reptile heat pad on a rheostat. Stick a clean thermometer into the mix and adjust the rheostat as needed to let the soil temp stabilize at about 70-80 F. Do this during the day so that the temp is adjusted for the added heat of the sunlight.

Push the well-scabbed end of the cactus into the mix about 1 inch for every foot of cactus height. You will note that this depth is exactly half-way down into the mix. You only want it deep enough to stabilize the cactus a bit. It doesn't ever actually need to sink any deeper than an inch, but the cactus must be supported somehow to remain still during rooting. No frisky felines, IOW. tongue.gif

Spray the sandy mix with water when it dries out. Pedros may take a bit more water, but it really isn't necessary. The soil can remain just barely damp for many cacti, but desert types (like lophophora) need it to be dry. Watering heavily will not hurry rooting at all. In fact, it only promotes rot... but, like I said, Pedros are pretty hardy.

Check for roots in about 20 days. Some root sooner; some take much more time. To check, let the soil dry out and simply lift the cactus gently straight up and out of the soil mix. Do not wiggle or angle the cactus! Just slowly lift straight up. Check carefully around the areoles and pith ring for fine root threads or bulges. If there are no apparent roots, gently set the cactus back into the dent in the mix from whence it came and press a bot of mix around the edges if needed. Spray with water, and let it go at least another 15 days before checking again.

If the cactus begins to tilt toward the window, just carefully turn the whole apparatus 180 degrees. By the time it starts growing, however, it should be rooted.

When it finally sets some nice fat roots, let them harden off a bit by laying the cactus on it's side on a table with the roots dangling over the edge (so as not to crush or bend them). Let the roots harden for about 3 days.

When you're ready, just be gentle potting it up. Hold or, if the cactus is large, have someone else hold the cactus hovering in the pot while you gently fill around the roots and base with soil. Press the soil down very gently with flat fingers. Allow the cactus to sink down if you feel your pressure tugging at the roots. You'll get a feel for it as you go. wink.gif


Posted by: ShroomZilla May 13 03, 06:27 PM GMT
Thanks Ion!!

That was freaking wonderful!