Brian:

What's often missed on this forum is that the conditions needed for maximum growth and vigor are not the same as conditions needed to maximize eating quality of the fruit. Most fruit needs a long period of moderate water deficit to maximize eating quality. Moderate vigor is also better than high vigor. These factors cause the plant to increase the osmotic potential of all the plants cells in order to extract water from drier soil. The plant does this by increasing sugars in it's cells including the fruit. If you want sweet fruit, think long periods of moderate water deficit.

The Gritty Mix dries out very well, so I'd think the sugar quality would be excellent.
As regards growth, I think we're talking about vitality (rather than vigor, which is genetically endowed).
I agree about aiming for moderate growth (using just enough nutrients to sustain healthy growth).
By maintaining adequate levels of nutrition, as opposed to 'luxury' levels, the plant's growth will be
more balanced (and should produce well, too).

Josh

I think I explained this to you somewhere else, Brian?

I agree with Josh .... and good point about vitality vs vigor, Josh!

At some point, root congestion is going to become the factor most limiting to growth. Because the gritty mix is so well-aerated, if you have two plants with all else equal but the soil (and one soil being a heavier, peat-based mix), the plant grown in the gritty mix will perform better because of superior aeration and lack of a PWT. This means root growth will be more robust and the plant will reach a state of root congestion that limits the plant BEFORE the plant in the heavier soil. Superior top growth would also accompany the more robust root growth up until the point where root congestion becomes limiting.

If you want to get the most out of your plant using the gritty mix, you'll want to grow in larger volumes of soil, not smaller. One of the significant advantages of soils that don't support perched water is that there really is no upper limit to pot size. You can grow tiny plants in huge volumes of soil if you prefer, with no concern for root rot or impaired root function due to the saturation associated with heavier soils and over-potting, BECAUSE of the soils less desirable physical characteristics.

Certainly though, if you want to, you can deal with the effects of root congestion and grow in reduced volumes of soil. I have hundreds of potential bonsai and bonsai in small pots that do much better in the gritty mix than they would in a heavier soil.

All plants are genetically programmed to grow well and look attractive. The reason they sometimes don't is found in the grower's inability to serve up the cultural conditions that allow them to reach their potential. Growing well is no more than eliminating limiting factors to the greatest degree possible. The best grower is the grower that identifies and eliminates as many limiting factors as possible, to the greatest degree possible. It's THAT simple.

Al