Re: Permaculture for a dry climate
Sue, the area that we are going to set up our homestead is considered semi-arid (about 12" of rain a year). Yes, I think it is entirely possible to design a system through rainwater collection, swales, run-off ponds, greywater recycling, judicious mulching and deep-rooted/drought tolerant plants to transform a dry plot of land to a lush food producing garden. But it does take some planning, some tricky handiwork, and thinking about water like never before.
First thing you need to do is collect as much rainwater/snowmelt as possible… either using rain barrels or a buried sotrage tank. Every single roof surface should be hooked up to a collection gutter, and your roof materials need to be benign (say goodbye to those asphalt shingles). Then you need to use that water as many times as you possibly can, putting it in the soil not on top or in the air (bye bye sprinklers) and keeping it trapped in the soil with various mulches. Eventually, if you plant your different species so that they form natural barriers and canopies for each other, these little microclimates will help retain water themselves. Nitrogen fixing plants are great, especially if you invest in some legumious grasses with deep roots that are native to your area… when you mow these grasses, the roots die off to the lentgh of the leave blades which puts nutrients into the soil and leave lots of little pockets for water to get trapped.
You might have some problems with certain varieties of water-loving plants… like melons… but if you can provide them a little extra water without robbing the rest of your garden, you can manage a few of the more drought tolerant varieties. It definitely requires a whole-systems approach rather than a single-solution mindset, but it’s totally doable.