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Rooting & support

Cut & heal

Cut the piece you want to root from the cactus with a clean, alcohol sterilized knife. Place it in a moderately cool, dry shady location to allow the base to form a scab. This will take 2-3 weeks. An electric fan can help dehydrate the end in 24 hours, then let it rest for a couple of weeks.

Sterile rooting medium NONSENSE!
Why a sterile medium? The "experts say" If you have problems with rot, then use sand or vermiculite as a rooting medium. "The use of soil can cause rot since it contains bacteria." Nonsense! Soil contains beneficial bacteria!

Rot is from too much water and/or from using anerobicly (BAD) composted material. Anerobic compost stinks and has pathogenic bacteria in it! Good compost is aerobicly composted material and is sweet smelling humus that has beneficial bacteria! World of difference.

If you don't know what you are doing, then read a book on organic gardening. This is basic knowledge; not rocket science. Heck, just go buy a bag of cactus mix potting soil at a garden center/Wal-Mart, Home Depot, Lowe's, etc.
• Place cutting in a container of soil prepared as I describe on the Soil pages. Logs can be half buried horizontally.

• Place in a warm partially shaded place (avoid direct sun). Moisten the media with a very small amount of water--you just don't want "bone dry" soil or the soil bacteria will die. Do not water for 2 weeks to a month and when you do , do it very lightly! If you water it like a plant before it roots -- it will rot.

The trick to rooting is to stress the cutting into forming roots. It has to have warm soil and bright daylight. If it is too cool, too little light--it has no need to form roots. You can't root cuttings in cool weather or the winter unless you heat the soil and provide bright light.

When roots start to form, water very lightly.
Wait until  the soil feels dry when you stick your finger into it before watering again. After about 4 to 6 weeks, gently lift the cactus see if it has roots yet. If rooting has not occurred, rebury it and check again in two weeks.

• It can take weeks or months to root a cutting. Variables such as the time of year, local temperature and duration of sunlight, etc. are all factors.

• Keep the cutting warm during the entire process. Warmth always stimulates rooting.

• Maintain low exposure to direct sunlight; use shade netting (shade cloth) to make a shade nursery for your cuttings.

• Cuttings will sometimes root in only a few of weeks in spring and summer.

When the cutting has roots (congratulations!) increase watering and fertilize. When the roots form a substantial ball you may transplant it into a container with a compost rich, well draining soil mix.

Checking roots on a small tip

Short tip vs tall
If you root a tip 6 to 12 inches tall it will easily stand up. But when rooting 18" to 36" tips support must be provided. Shown at right is a 24 inch tip held with twine between redwood poles.

One way to hold up a tip
Garden stakes made of 1 inch square, 6 foot long redwood are commonly sold for use in vegetable gardening. At right are two such pieces used as supports. Deck screws, 1" long, are driven through the outside of the pot into the redwood.

Perlite potting soil

Prepared 50% perlite with 50% garden soil works for me. The pot at right was filled about 2/3 of the way, the tip set on in it, then more mix added
so that the tip sets about 3 inches deep. The buried end will sense that it
is underground and in time sprout root buds to search for water.

Garden twine
In the picture garden twine was used to tension the two poles. Doing so pressed gently yet firmly enough to hold the tip in position. It cannot fall
to either side because the string is in a "V" formation as it approaches
each pole.

Miracle Tie
Or use this product called "Miracle garden tie" by the L.E.Cooke Co. [http://www.lecooke.com] sold at retail garden stores. It is a nicely soft, stretchy, but tough plastic ribbon. About $3-$4 per roll. I prefer the wider tape.

More info: Shade nursery Soil + 50% perlite works for me. Lay off watering to prevent rot.
How long does it take to root a cutting? Depends on soil temperature
Gardening is such hard intellectual effort sometimes; mix dirt, fill pots, stick in cuttings.
This cutting has been in soil since October without rooting. Why? Because it was too cold. Notice how healthy it looks. It just went dormant for the winter and would not root in cold soil. It never needed water because its stoma (breathing pores) open at night to get CO2 and H20. It never rotted because I kept it in dry soil. But now its ready to rocket! Spring will break that dormancy as the sun shines longer every day and the soil warms up.
See our friend? We put him back in soil and will check
on him next month. I'll bet he has some root buds by then.
You can root any tip, log or just a chunk. It is very easy if you set up a shade house with bright filtered light. Mix up sand + perlite + garden soil. [avoid peat moss and vermiculite because these hold onto water like sponges] Or you may use sterile soil to prevent rot [bake at 400 degrees in an oven for an hour, let cool]. Or use 100% sand or perlite. Any sandy, well draining soil is fine.
The soil needs to be warm, over 60 degrees or so (I guess), to stimulate rooting. Spring time weather is fine for this unless you live in a cold place; but this is all standard gardening knowledge. You can't get vegetable seeds to germinate in cold soil either. To start tomatoes you usually use a soil heating pad, or I've even used cables you lay in the dirt (for a greenhouse). Most vegetables require 60 to 70 degrees and I guess rooting a cactus isn't much different temperature wise.

You can certainly start rooting your cuttings in the house because that is warm. Here in California I can root cuttings outdoors from Spring all through the Summer. By September they slow down and go dormant around October when it cools off.

Soil mix
You can root in 100% sand if you like. Even 100% vermiculite--but I have not tried it. I just use 50% soil and perlite. You want to avoid wet, soggy soil as that will rot the cutting. Your cutting does not need water to root! No water. Got it? Its a cactus. It breaths through its stoma (pores) at night to get CO2 and water vapor. Watering a cutting is dumb--it has no roots to absorb the moisture. But the soil can be a bit damp; it does not have to be "bone dry". Don't obsess. Nature will go into automatic mode and root it for you. Often you find stuff grows best if you leave it alone.

Check every month for roots
After rooting in sandy soil put it in a bigger container and I recommend you mix in earth worm castings and/or real organic compost (buy it from a local organic gardener--do not use the garbage they sell at Home Depot!).

Big Pots=Big plants
The larger the pot the larger the root system will be. The more roots, the faster the plant will develop. To get large root systems you need rich, organic soil that is easy for roots to grow in. It should have lots of sand or perlite so it does not compact and cut off air & water. Thick clay soils are bad, but can be mixed with 50% sand and perlite to become OK. If you grow in a large container always go with 50% perlite to help avoid soil compaction (hard soil).

San Pedro wants to grow to tree size unless you restrict the roots in a pot. You know how Bonsai works? To achieve huge plants you need to put them in the earth so the roots can grow as large as they wish. Dig a big hole and back fill it with mixed sand, perlite, and compost. Then top mulch your San Pedro continuously with at least 2" of organic compost. Get earth worms living in the soil around the San Pedro. You want a 12 foot tall cluster, right?

Why organic?
Because you have to encourage symbiotic microbial life with the roots. Then the plant can really drink up tons of organic nutrients. There are thousands of tiny root hairs that look like a fine fuzz. You want to "inoculate" your plants with beneficial microorganisms. Buy fresh worm castings from a local person who raises earth worms. That is a great way to jump start this. Mix in about a 2 inch thick layer on top. Earth worm castings are alive with microorganism that will set up the right symbiotic relationship with the roots. Trust me on this one. You want a 12 foot tall cluster, right?

email bobcat@sanpedrocactus1.com
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