[permaculture] heavy clay and cover crops, more on shade
raincascadia at yahoo.com
Sun Mar 15 15:35:28 EDT 2009
Loosening up heavy clay with cover crops is very slow. Our native grassland here is composed primarily of grasses and clovers, in other words, cover crops. The soil is too tight and dry for the production and integration of much organic matter. Forking and irrigating it could help. Gypsum might also help, though I hate mined inputs like this. Dumping a foot of organic matter on top would definitely make a difference, especially if it was forked or disced in after a couple years, but getting this much material can be a challenge. Pioneer trees are basically the simplest solution, though a very slow one. Larry mentioned planting root crops like daikon, chicory, etc., and this is also helpful if you have the water for irrigation. The solution depends on what you have available.
I forgot to mention olives and citrus as other trees that can produce well in the shade of Mediterranean climates, in addition to the usual suspects. I have lists of plants and their sun/shade needs in my book, West Coast Food Forestry, which is available from me or online.
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