Is this Sulco too plump?

[Steve Johnson]

Hmmm, here's an interesting problem, and one I totally didn't expect...

Last year was a mixed bag of pots I was using for the collection. Some were plain terracotta, others were plastic, and still others were terracotta which I started waterproofing last May. The plastic pots were an experiment, but I ended up ditching them for a few reasons. IMO waterproofed terracotta has been a blessing, so the March repotting project did what I wanted --
A. making sure that nothing is over-potted these days, and B. also making sure that every cactus is now in a waterproofed terracotta pot. I'm fully aware of what happens when water and nutrients that should be going to cactus roots are instead drawn away by evaporation through porous clay. That extent of evaporation is largely a non-issue, and apparently I was correct about waterproofing. Here's my Gymnocalycium ochoterenae vatteri as I've never seen it before:



Those roots are really working -- maybe too well? Bad habits are continuing to follow me as I water blindly by schedule when I should be paying more attention to what some of these plants are supposed to look like. Don't think the vatteri is supposed to look nearly that plump, so I'm putting it on a no-water diet until it flattens out. (Believe it or not, this is actually going somewhere. )

I don't have enough experience with Sulcos to know how plump they should be. The callichroma longispina has a honkin' big set of taproots, although I'm very hesitant to make assumptions about how often it needs water. I'd like a critique on this, so let me know what you think:



I've been watering it every 2 weeks since the beginning of April -- my standard Spring routine unless I already have experience with cacti that don't need it as often. So is the callichroma looking normal, or is it too plump? Now would be a good time to let me know, as I have it on the watering list for next weekend. I'll ask the same thing about my Sulco rauschii, which is the plumpest I've seen so far. Any and all thoughts about this would be greatly appreciated.

Thanks for your help, my friends!

[Subverted]

I think that you are probably over-thinking this just a bit. The plants look healthy to me but of course photos can only give a certain amount of information.

Keep an eye out for any splitting and if you notice anything ease up on the water, obviously. Other than that it is just a matter of ensuring that things dont stay wet for too long at one time which it sounds as if you have worked out pretty well already.

[Steve Johnson]

I think that you are probably over-thinking this just a bit.

Better that than not asking enough questions and letting things happen that could've been avoided with more attention to detail. With that said, I do appreciate your feedback -- all part of my learning experience. Thanks!

[Sulcofan]

Looks just dandy to me Steve. A cracking plant

[iann]

Thought I'd replied to this already? Maybe not. Looks OK to me. Will probably get a bit less fat as summer progresses.

[Steve Johnson]

Looks just dandy to me Steve. A cracking plant

Thought I'd replied to this already? Maybe not. Looks OK to me. Will probably get a bit less fat as summer progresses.

Thanks, guys! The callichroma is a beauty, and I'm glad to know that I haven't let it get overly plump. As to the Gymno, it'll try to avoid keeping it looking like the Michelin Man.

[CactusFanDan]

I should be quiet when it comes to splitting plants. I noticed a nice, big split on a seedling Copiapoa fiedleriana today. Seems I'm great at splitting Copiapoas. I managed to split my very clean, very nice C. cinerea last year. So yes, a warning about the hard-bodied Copiapoas! They split easily. Not so sure about the soft-bodied ones, but I've had no splitting from them yet.

[sundanz]

What do you do when a plant splits? Throw it away??

[Steve Johnson]

What do you do when a plant splits? Throw it away??

Just speaking for myself -- no. Understand what caused the split, and try not to do it again. Watering frequency is under the grower's control, so this is a matter of whether or not we're paying attention to how often the cacti want water. Unfortunately some of that experience has to come the hard way. So far it's happened only once with one of my Turb polaskiis, although it's enough to know that 20-20 hindsight kinda sucks.

[CactusFanDan]

What do you do when a plant splits? Throw it away??

Nah, unless it's particularly nasty and the plant won't survive it. Just keep on growing them. Splits soon heal up and turn into scars, which other than being unsightly, aren't a problem.

[SnowFella]

Just wait untill you start splitting collumnars in the ground, nothing you can do but to stand back and wait.
This is one of my uglier plants in the ground, Pilosocereus of some sort, that I noticed a split on the other week even though it hadn't rained for weeks. Since then we have had a decent amount of rain so I'm expecting it to get worse! Guessing it's because the plant only has 4 ribs with just about no valleys between them so there's just no room for expansion without a split happening.

Split is about 2 inches long.

[CactusFanDan]

I'm pretty sure I've split a little columnar cutting in a pot recently. I think I was a bit heavy-handed when it came to seeing if it had good roots yet or not. Not the end of the world, though.

[lockheed]

@Steve Johnson,

You might want to add a little (I do mean little) amount of limestone gravel to the mix. It is supposed to prevent plants to grow beyond their capabilities of healthy, optimal sustenance (check out Cacti Soil Hexalogue).

[Steve Johnson]

@Steve Johnson,

You might want to add a little (I do mean little) amount of limestone gravel to the mix. It is supposed to prevent plants to grow beyond their capabilities of healthy, optimal sustenance (check out Cacti Soil Hexalogue).

I did go through the Hexalogue -- very interesting read, and it was my first acquaintance with the concept of using limestone (or gypsum for certain species) as a natural growth inhibitor for cacti that are being kept under pot culture. However, I wouldn't run out and look for limestone (or gypsum) to use in my calciphytic cacti unless I have some supporting evidence to back up the author's claims. If I see it, then I'll look at what I have in my collection and identify which of my cacti are calciphytes. Everything is settled in and growing already, but I could adjust a small batch of my pumice/DG mix to include maybe 10-15% limestone/gypsum when I repot the calciphytic plants.

One calciphyte I can identify right now is Epithelantha micromeris. I got mine from the California Cactus Center at the beginning of May last year, and the plant tag recommended adding 20% gypsum to the soil. (This may be neither here nor there, but my mix is soil-less.) I asked the nursery people if there would be a problem if I don't add in any gypsum, and they said "no, your Epithelantha should do fine". Let's put the author's claims to a little test concerning normal vs. optimal growth with this example...

Here's what the micromeris looked like the day after I transpanted it on 5/6/12:



The roots took their own sweet time getting established. Didn't overdo the watering frequency, but the micromeris was very slow to respond. After about 4 months of acting like it didn't get any water at all, at least I was able to see just a few hints of life going on above-ground. Here it is in mid-August, shortly before the plant finally started responding to water:



Now I'll give you an eyeful of what the micromeris looks like these days:



The micromeris still looks thirsty, but a darn sight better than anything I've seen out of it before. So there's the question for us to consider -- is the plant growing normally, or is the absence of gypsum in the mix forcing it to grow beyond its normal limits? I'll be very interested in any responses that come in, so answer away!

Getting back to my "Michelin Man" Gymno, there's a little detail I forgot to mention. Ignoring my usual if-it-ain't-broke-don't-fix-it rule, I decided to tinker around with adding some soil to the pumice/DG. One of the candidate soils I investigated happened to be a product called "Ancient Forest Humus" coming from Alaska through the RePotMe website. Definitely not compost in the strict sense of the word, although Ian did point out that it's still a forest product and therefore not the best for a cactus mix. His feedback on the matter came after I decided to give the Gymno a "live fire" test by repotting it in a 40/40/20 pumice/DG/AFH mix. Long story short, I can tell you this -- the pumice/DG and test mixes went from wet to bone dry pretty much at the same time. The big difference was that the pure mineral mix dries out at a steady rate, while the AFH in the test mix held its moisture longer before drying out. Now I know that's how I ended up with the Michelin Man. So guess what I do tomorrow? Unpot the Gymno yet again, get rid of the test mix and go back to the soil-less mix when I repot it. I'll have a good look at the roots (pics to follow), so at least I'll be able to see the progress below-ground there. Since there's plenty of growing season left, now I can just let the plant do its thing and keep it from blowing up like a water balloon again.

[iann]

I don't add gypsum to my Epithelantha soil. Epithelanthas are not gypsum endemics. I'm not even sure they are always found on calcium-rich soils, although certainly a lot of them grow on limestone. There are some growers who refuse to entertain limestone in their pots and add gypsum instead even where the wild plant is a limestone endemic. The chemistry behind this is somewhat dubious and I certainly don't do it. I add limestone chips (10% or so) to the pots of some cacti, including Epithelanthas.

The Gymno looks great. I don't think I'd want to move it.