Farmers are trying to improve the ability of water to reach the roots of plants by improving the organic composition of the soil. According to an article on agronomics in the January issue of Successful Farming, it takes five years to improve soil conditions 0.01% of no till composting. Water will penetrate the soil 0.4 inches more readily when 0.1% of the soil is improved with organic material.
It is hard to imagine that it takes 100 years to produce one inch of humus in a deciduous forest. Yet we can use worms to compost 50% of their body mass daily.
The reason that Square Foot Gardening works so well is that most of the material in each square is organic. When using commercial composts however the percentage of inorganic material may be significant. When using worm compost the percent of inorganic material is very small. The other materials of peat moss (would prefer coconut core) and vermiculite both absorb water easily. The plants can only go through the process of photosynthesis if there is a sufficient supply of water and proper root development.
I am currently using worm castings for 25% of the Mel’s Mix formula. The roots always have access to plenty of water because of the organic composition of the medium used.
The equation here is to produce more yields in a limited amount of space. In addition, more nutrients are absorbed when readily available to the roots. We are all looking for mineral rich vegetables. Microbes in the soil create a natural environment for plants to grow without pest controls. A great book on this topic is Teaming with Microbes.