Hi, I'm pretty new to permaculture, I've read a lot but just bought a house and am getting to put it into practice for the first time. My backyard is completely xeriscaped and I'm looking for advice on a cover crop mix for pretty much slightly soily sand.
There is also a tree back there that gives the area some summer shade.
I've been looking at mustard and comfrey because of their huge root systems and mineral mining, but what does well in sand for nitrogen fixation? Succession-cover cropping would be fine, I don't plan on turning the area into my perennial bed until planting time 2018.
Can anyone give me some advice on techniques and plants that would help me? Thanks