Phals, s/h and short pots

[Ray]

There really isn't any such thing as a LECA that wicks "too well." In fact, the better the wicking, the less tendency there will be for root suffocation. Picture this scenario describing the conditions within the pot, bottom to top:

🔸In the reservoir, the particles are saturated, and there is absolutely no space between them that are not full of water.

🔸Move up slightly, and you are in that range where the particles are still saturated, and surface tension can hold the water well enough that the void space is still mostly full.

🔸Move higher still, and both the degree of saturation and filling of the interstitial spaces begins to decrease.

🔸Higher still, and there is zero interstitial "clogging" by the water, and the saturation decreases further.

🔸In an "infinitely-tall" pot, eventually you get to no water at all, as it has all evaporated, having outstripped the LECA's ability to wick it up fast enough.

If the LECA wicks well, that transition zone from the spaces being 100% full of water to 100% empty will be very short, making the "breathability" for the roots better, and the height of the column that still carries some moisture will be tall, but that last parameter is controlled by the conditions affecting evaporation rate, as well.

I will add that I now consider the moisture gradient allowing the plants to "find their own preferred depth" to be incorrect, as every plant I have ever grown in semi-hydroponics will eventually grow its roots right down into the reservoir, fully submerged.

All that rambling explanation out of the way, if the issues with the phals in the short pot is with established plants (i.e., they are roots that grew in that pot - we expect existing roots to fail when moved to s/h, and to be replaced by new ones optimized for the conditions), then there is another cultural parameter that's out-of-sorts.

If, on the other hand, these are the pre-existing roots that are failing, so what? (Unless it was moved into S/H at an inappropriate time.)