Bryan Jasons wrote:Do we know that gypsum when added will do nothing useful in sandy soil?
Bryan Jasons wrote:How do we know that anything added will be leached in a sandy soil?
I think the literature (both science and general garden info) has pretty well established that sandy soils don't hold minerals, water, fertilizer well. That's the domain of humus. And the literature is pretty clear that water is the medium which allows the cations to work with the bacteria and roots. (
http://extension.psu.edu/business/start-farming/soils-and-soil-management/soil-quality-introduction-to-soils-fact-sheet-1) is a pretty good overview; FAO's
The importance of soil organic matter:Key to drought-resistant soil and sustained food production (
http://www.fao.org/docrep/009/a0100e/a0100e00.htm) is another resource and it goes into more detail. I'm sure others could bring other resources they've found worthy.
Clay particles are much smaller than sand. They significantly increase the available surface area for nutrients to hang onto and create micropores to slow down the flow of water. Both are good things; at least until there is too much..... But that is another topic.
Bryan Jasons wrote:Also, the importance of being holistic and thorough - like Coleman or Soloman are - isn't lost on me. But I never planned on using this area for vegetables; I was thinking cover crops, sweet potatoes, millet or some other easy to grow crop that I have experience with. I already have vegetables gardens with mulch and cover crops being used in other places.
Even a cover crop needs organic material in the soil. An advantage of cover-cropping is it is generating green manure, but it needs some nutrients to grow. And we seem to back to how much fertilizer will be available to the roots. Success by light and frequent amendments of organic material and equally light and possibly more frequent watering to have a crop that can be turned under might work.
In any case, knowing where whatever amendments we put into soil ultimately goes is a good thing. Saves $$$, saves water, saves time and effort, being aware of water and soil / subsoil ecology are important.
At this point, it might be best to ask if a $20 home garden soil kit test has been run? Or an Albrechtian lab soil test? What sort of fertilizer / mineralization / Cation level amendments have been recommended? Is there evidence that Al levels need to be addressed?
