Answer: You have some excellent perennials. I think wildflowers would be a good choice, in keeping with the natural plants. Planting more "traditional" annual flowers might look a bit odd. I'm going to recommend two catalogs that contain alot of info on flowering plants specific to our West's challenging growing conditions. High Country Gardens, http://www.highcountry gardens.com and Plants of the Southwest, http://www.plantsofthesouthwest.com. Another source might be of interest to you as it has native vegetable crops that tolerate and even thrive in very dry conditions: Native Seeds/SEARCH in Tucson. Their website is http://www.azstarnet.com/~nss/.
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