Repotting in my favorite new soil blend

Plants often let us know what they need. All we have to do is look. Some cases are more transparent than others, but it doesn't get more obvious than this:

Acanthocereus rosei, a scrambling/climbing cactus from Mexico with beautiful flowers

This used to be a perfectly square pot. Doesn't look so regular anymore, does it? 

The ripples and bulges aren't caused by the plastic melting in the sun. It's the plant telling me it wants a bigger place to live. And here it is:

Acanthocereus rosei in larger pot

My new favorite soil blend is Ultra Potting Mix from American Soil & Stone in Richmond, CA. According to their website, Ultra Potting Mix is:
Our premier coconut coir based potting soil. Coconut coir is an environmentally friendly alternative to peat moss. Fertilizers are pre-blended so this soil is ready to use.
Contains: Coconut Coir, Sand, Red Lava, Dolomite Lime, Nitroform 38-0-0, Iron Sulfate, Triple Superphosphate, Calcium Nitrate
Pumice and Ultra Potting Mix, both from American Soil & Stone

I have friends in the Bay Area who have achieved remarkable results using American Soil & Stone's Ultra Potting Mix, both for seedlings and for more mature potted succulents. Depending on the application, they combine it 60:40 or 50:50 with pure pumice for added drainage. I'm following their lead. My soil blend looks like this:

Repotting the Acanthocereus rosei above was just the beginning. Next up were some aloe and agave seedlings, the only survivors from a batch decimated by whatever fungus causes damping off. Ideally, I would have wanted the seedlings to be bigger before disturbing them, but they simply weren't growing in these plastic tubs.

Agave 'Magnifica' and Agave mckelveyana × utahensis seedlings

Aloe decurva seedling

All potted up:

To keep them going, I will mist them frequently until they've grown more roots

What you see in the photo below are aloe seedlings grown by my Bay Area friend John B. from open-pollinated seed collected in December 2018 at the Oakland garden of John Miller (president of the Institute for Aloe Studies). These seedlings have spent most (if not all) of their lives in Ultra Potting Mix/pumice, and they've thrived:

Aloe lukeana and Aloe ikiorum, open pollinated so possibly not 100% “pure”

Here they are, repotted in #1 cans:

I didn't have to look very hard to find more repotting candidates:

Echinocactus platyacanthus

Aloidendron dichotomum; it hard become bonsai'ed because of the limited space for its vigorous roots

Aloe pluridens

Agave stricta 'Nana', struggling in this hypertufa pot for years (maybe leaching from the cement?)

Hopefully it will do better in fresh soil

In addition, I have quite a few aloe seedlings that will need repotting before too long:

And since this blog is called Succulents and More, here's a non-succulent that got a larger home:

Daviesia cordata, a gift from Troy at Waltzing Matilija. The “after” is essentially the same, just in a larger square pot. May this Western Australia native with beautiful flowers thrive so I can put it in the ground in the fall.

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  1. I've never seen a potting mix with a composition like that down this way. You'll have to provide an update in 6-12 months.

  2. Interesting mix. Have never heard of nitroform. Cactus potting mixes available here are just peat with some added perlite. I prefer coir and mix it with some Seasoil, perlite and grit and have good luck with it so far. Transplanting the Echinocactus must have been fun with those long spines.

    1. Nitroform is a slow-release fertilizer, from what I was able to gather.

      Chicken grit is great, as is 1/8" lava rock, gravel, etc. Anything that improves drainage.

      Cactus spines: I have a new pair of cut-resistant gloves that work great for that purpose (

  3. What an interesting soil mix. Lots of added nutrients. Looking forward to seeing these babies in six months. And love the Tabasco bottle for scale!

    1. Lots of good stuff in that soil mix. I imagine many ultra/premium soil mixes are similar. What I like about this brand is that it's coir-based and contains no peat (peat holds too much moisture for my purposes).

  4. If it works, it works! :) That is a cool cactus. Poor stricta nana. A fine little Agave--hope it recovers.

    I use a mix that is mostly pumice, with some garden soil added for nutrients--very heavy so the pot doesn't blow away in Santa Ana winds. I avoid pearlite because it floats.

    Now I thought that Aloe species would not ever self-pollinate--true or false? My capitata seedlings by the foliage seem to be hybrids of either vanbalenii or ferox. Still waiting for flowers.

    Tabasco bottle for scale--too funny!

    1. I was frantically looking for something to include in the photos that would provide a sense of scale. The Tabasco bottle was the first thing I found, LOL.

      Perlite is nasty, for that very reason. I knocked over a bag once--worse than Styrofoam peanuts!

      I think aloes do self-pollinate. You just need flowers of slightly different age, i.e. some with viable pollen and some with receptive stigmas at the same time. Theoretically?

  5. Beautiful cactus! I keep A. tetragonus, had two huge blooms last week. Yours must be rare, I can’t see any on eBay. Reminds me of a Peniocereus.

    1. Nathan, it used to be Peniocereus rosei but it was transferred to Acanthocereus in 2013, according to the Huntington ISI web site ( I got it from Jeff Moore at Arid Adaptations in Tucson, AZ (


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