Amending a barren yard with compost: dedicated weed barrier or no?

Question

I've got a pretty typically barren New Mexico (zone 7a) yard, and I'm thinking of trying some intensive amendment to control weeds, improve the soil, and add some visual interest. What I've read here as well as some other places has led me down the path of putting a zillion cubic yards of compost from the city water treatment plant over the existing totally barren desert ground. It's very cheap and made up of a great-looking mix of biosolids, yard trimmings, and animal stable bedding.

My next thought was that the weeds will love this stuff, and so I ought to cover all this compost with a cardboard weed barrier. But I'd need to anchor the cardboard down somehow, and it will look ugly. So I'd better put a top layer of maybe some nice-looking bark mulch over it.

But this all now sounds very complicated, and the engineer in me doesn't like the inefficiency of using two additional layers simply to facilitate weed control. And acquiring enough cardboard will be tough. Is there any way I can stop the weeds using just the compost?

After a few years of this, I'd like to plant a southwestern-friendly groundcover, but I'm not sure what yet (Current thoughts are Blue Grama grass or hardy Ice Plant). Should I maybe plant whatever groundcover plants I want right into the compost and use them to out-compete the weeds and block the sun?

Answer 1

Actually, what would be ideal is to get short-term cover crops on the area soon after amending, and either till them in when mature, or dump new compost on them, whichever come first. They will help keep the weeds down, and help keep the available nitrogen in cycle (so it doesn't leach). Any fast growing annual cover crop will do.

I actually think it would be better to have a weed cover than covering with cardboard and bark. Your idea is great, getting all this new organic matter down, and will really improve your gardening experience.