Two of the most notable attributes of a properly made 'gritty mix' are the fact it lifts the tax levied by excessive water retention, and it's adjustable for water retention; so, if a medium doesn't support any notable amount of perched water, the pot size/ shape/ depth shouldn't matter ...... as long as you're not under-watering and are being reasonable about how often you water. If the gritty mix isn't appropriately screened to remove the fines, there's no reason to expect it to perform significantly better than a long list of other mediocre media, which means there honestly wouldn't be any good reason to go through the effort/expense of making it. That said, I haven't found anything that comes close enough to how well it works when it's properly screened to entice me to even think about changing.

Can someone talk about how deep the roots grow on this plant, and does it like a deep pot? How deep the roots run on in situ plants has nothing to do with how deep they'll run in a container. If you have an adequate volume of air:water in the medium, plants normally considered to be shallow rooters in situ will happily colonize the entire soil mass of even the deepest pots. What kind of soil should be ideal for it? See below.I've given a considerable amount of thought to what properties the ideal medium would embody. What I come up with is: What kind of watering pattern is ideal? It seems to like a lot of water (by succulent standards) to stay in peak condition.

IS 'X' A GOOD SOIL?

I think any discussion on this topic must largely center around the word "GOOD", and we can broaden the term 'good' so it also includes 'quality' or 'suitable', as in "Is X a quality or suitable medium?" How do we determine if medium A or medium B is a good one? And before we do that, we had better decide if we are going to look at it from the plant's perspective or from the grower's perspective, because often there is a considerable amount of conflict to be found in the overlap - so much so that one can often be mutually exclusive of the other.

We can imagine that grower A might not be happy or satisfied unless knows he is squeezing every bit of potential from his plants, and grower Z might not be happy or content unless he can water his plants before leaving on a 2-week jaunt and still have a weeks worth of not-having-to-water when (s)he returns. Everyone else is somewhere between A and Z; with B, D, F, H, J, L, N, P, R, T, V, X, and Y either unaware of how much difference medium choice can make, or, they understand but don't care.

I said all that to illustrate the large measure of futility in trying to establish any sort of standard as to what makes a medium 'good' from the individual grower's perspective; but let's change our focus from the pointless to the possible. We're really only interested in the comparative degrees of 'good' and 'better' here. It would be presumptive to label any medium "best", though 'best I've found' or 'best I've used' CAN sometimes be useful for comparative purposes, but that's a very subjective judgment. Let's tackle 'good', then move on to 'better', and finally see what we can do about qualifying these descriptors so they can apply to all growers.

I would like to think that everyone would prefer to use a medium that can be described as 'good' from the plant's perspective. How do we determine what a plant wants? Surprisingly, we can use %s established by truly scientific studies that are widely accepted in the greenhouse and nursery trades to determine if a medium is good or not good - from the plant's perspective, that is. Rather than use confusing numbers that mean nothing to the hobby grower, I can suggest that our standard for a good should be, at a minimum, that you can water properly. This means at any time during the growth cycle you should be able to water your plantings to beyond the point of saturation (so excess water is draining from the pot) without the fear of root rot or compromised root function due to (take your pick) an excessive volume of water or too little air in the root zone.

I think it is very reasonable to withhold the comparative adjective, 'GOOD', from media that can't be watered properly without compromising root function, or worse, suffering disease from one of the fungaluglies that cause root rot. I also think anyone wishing to make a case from the plant's perspective that a medium which can't be watered to beyond saturation w/o compromising root health can be called 'good', is fighting uphill against logic.

So I contend that 'GOOD' soils are those we can water correctly; that is to say, we can flush the medium when we water without concern we would be compromising root health/function due to long term retention of excess water. If you ask yourself, "Can I water correctly if I use this medium?" and the answer is 'NO' .... it's not a good choice .... for the reasons stated above. Can you water correctly using most of the bagged bagged potting media readily available? 'NO', not without work-arounds in place, and we can talk about those.

What about 'BETTER'? Can we determine what might make a better medium? Yes, we can. If we start with a medium which meets the minimum standard of 'good', and improve either the physical or chemical properties of it, or make it last longer structurally, then we have 'better'. Even if we cannot agree on how low we wish to set the bar for what constitutes 'good', we should be able to agree any medium that reduces excess water retention and increases aeration ensures better potential for optimal root health than media which only meet some one's individual and arbitrary standard of 'good'.

All the plants we grow, unless grown from seed, have the genetic potential to become beautiful specimens. It's easy to see the absolute truth in the idea that if you give a plant everything it needs to prosper it will flourish. The better we are at it, the better our plants will grow. But we all know it's not that easy. Lifetimes are spent in careful study, trying to determine just exactly what it is that plants want and need to make them grow best.

Since this is a discussion, let's examine what the plant wants from its soil. It wants a soil in which we have endeavored to provide in available form, all the essential nutrients, in the ratio in at which the plant uses them, at a concentration high enough to prevent deficiencies yet low enough to make it easy to take up water (and the nutrients dissolved in the water). First and foremost, though, the plant wants a container medium that is evenly damp, never wet or soggy. Giving a plant what it wants to flourish and grow doesn't include a medium half saturated for a week before aeration returns to the entire mass, even if we only water in small sips. Plants might do 'ok' in some water-retentive soils if the grower is highly skilled, but in order to actually flourish as plants are genetically programmed to do, they would need to be unencumbered by media which do not remain wet/ soggy for extended periods.

What defines our proficiency as growers is our ability to identify and reduce the effects of limiting factors, or by eliminating those limiting factors entirely; in other words, by addressing those influences inhibiting the plant from reaching its genetic potential. Even if we are able to provide every other factor that influences plant growth/ vitality perfectly, it could not make up for a substandard medium. For a plant to realize its full genetic potential, every factor has to be perfect, including the medium. Of course, we'll never manage to get to that point, but the good news is, as we get closer and closer, our plants get better and better; and almost certainly, we'll find our growing experience more rewarding.

The only thing I can think of is that the deep pots are allowing the root zone to totally dry out, which they must like. I don't think that's it. More likely, it has to do with the fact tall pots are easier to grow in (when using media with a PWT) because they have a higher % of unsaturated soil.

If you're growing in the tall pot, the plant would have no reason to balk because of a PWT until the roots have colonized all the space above the PWT. When that occurs, there begins a cyclic death and regeneration of first the finest roots, followed by thicker roots, all due to lack of oxygen and adequate gas exchange. This effectively puts the brakes on top growth until root growth can catch up to the degree it can again support new growth, and can rob plants of massive amounts of potential. Because plants shed parts, which decreases their dry weight, the true measure of growth, it can be argued that unhealthy root system can rob a planting of more than 100% of its potential.

Al