Gita, yes I think we are saying the same thing, just in a different way. A bonsai tree would be a blatant example that it is possible to generally maintain a plant in a pot size that doesn't increase. Roots are periodically pruned, and to account for this lack of increased root mass, the above-ground parts must be maintained with pruning so there is balance, a healthy plant. Flipping the coin, it would never be possible to grow a full-size, mature pecan tree in less than the amount of soil that the root mass needed to support such a large entity would require. Avoidance of root rot is not inherently connected to pot size, or amount/proliferation of roots in a pot, though can seem to be when the soil does not allow roots to function in it. A soil in which roots can function well is necessary to have a great plant of any type in any pot size. Couldn't agree more!
If one wants a plant to increase in size, (which is certainly not necessary, a personal decision for every person for every plant,) it's necessary for it to be able to grow more roots. When roots run out of space to increase (thus enabling increase in the mass of above-ground parts it can support,) one (or combo) of several things can happen. Stagnation of growth overall. The foliage is compromised in appearance. Older foliage is discarded prematurely. And the theory that as a response to impending death, some plants will finally then produce an elusive flower in attempt to reproduce before perishing (which I've never heard applied to Dief, so a moot point regarding the plant being discussed.)
None of these scenarios appeal to me, so I try to avoid them by repotting periodically (completely replacing soil,) trimming roots when necessary, and sometimes providing a larger pot, depends on the particular plant and how it's doing.
The decision of when to repot a plant should be made by considering many factors, including time of year, and I didn't propose a time to do this for this plant, or to do it at all. If one is using the same soil type that purchased plants are sold in, deciding when to repot would have nothing to do with a change in soil type, so one might not feel any need to do it for a while, no problem.
It's not possible to know how long a newly purchased plant has been in its' current pot. A specific amount of time after purchase is not a factor I've ever considered, but usually do it within a few days because I am going to change the soil type, and like to get rid of tiny pots ASAP, before I knock them around or the wind blows them around. They are also usually a really dark color, which gets too hot when the sun shines on it (for those plants that are given direct sun.) Though in the middle of winter, like most people who only do this outside, I don't do much repotting. The few new plants I find during this time often wait until the next warm, sunny day. Looking at the roots is necessary to know how they are doing, the primary factor I consider.
Regardless of when one chooses to do it, if plants didn't almost always respond when I repot with vigorous new growth, I wouldn't be such a fan. When I repot a plant, it is to relieve stress, not increase it. If waiting is working better for you, that's excellent. Nobody wants anyone to change anything that's working well. I would encourage you to consider more factors than purchase date for your repotting decisions, especially for plants purchased in late spring and summer. Your abilities and skills to observe are probably far superior to an arbitrary measure of time. I would give you ample credit for being well able to make some decisions based on more concrete observances, factors.
Awesome pics, HCMC!
