I second the advice to get a soil test. It is relatively inexpensive, gives you a lot of information and comes back fairly quickly. You can get it through your U of A extension service, I think it is probably still up on Campbell. Until you do that, you're really feeling your way around in the dark. You should also let them know about your specific issues, there might be extra testing they can do for some common chemicals. Burning in and of itself should do no harm, only add to the alkalinity of the soil, but who knows what they used to suppress the fire...? No idea if that would affect it or no. Your soil will cake up if you are working wet clay, a big no-no. The mulch and compost is great for softening the soil and make it more moisture retentive, so checking it wouldn't be a big deal, and even then you can just scratch a little back. Mulching is *huge* in desert gardening, be it organic or even rock - anything to aid in cooling the roots, especially of non-desert plants of the type you're planting. I'm guessing you're saying that your soil is a mixture of sand and clay and not that you're mixing the two - that would = cement, and could be a part of the problem. Have you seen any of your plants growing well in your neighborhood? Also, longer term residents might be able to tell you if something happened on your site. But from your description, my best bet is that the holes that you're making in the caliche may not be sufficient to let the roots spread out; you might want to dig one of the dead plants out and see if it stretched out beyond the original root ball, or did they run into caliche immediately? You also want to test your drainage - caliche tends to form in sheets and if you had to get thru one, there is a good chance of another below it. Anywho, "they" now say that it's much more important to make a wider hole than a deep one, for the root spread problem precisely. BTW, I wouldn't waste my time asking folks at Lowe's for plant advice, although they put a few through some master gardener classes, few have the experience to do much more than scratch the surface of gardening. And steer manure... well.... unless it's really well composted, you're adding a lot of salt to an already salty soil. I saw an ad on Craig's list for horse manure today, you might think about that or the city of Tucson used to make compost out of their clippings and give it away. Hope this is helpful, best of luck to you!

The purple plums grow beautifully in Valdosta, I'm in Adel but lived in Valdosta for 32 years and have had purple plums in both places, never any problem.

Thanks Miriam, that makes a lot of sense. We are going to tackle the guest bath ourselves when life isn't so hectic. My 9 1/2 month old just started walking and DH just started his PhD and cant commit to tiling on a timeline. I do feel better though about pulling my own permits. I talked to our "contractor" and he said he would put on the Hydroban at no additional costs, and typically he just goes with the homeowner to purchase the construction items so they don't miss anything. ceezeecz thank you for the pocket door and permit info. I am going to check out Johnson hardware. Yes we do need threshholds I completely forgot about that. 8pmg I definitely think the TX market is different. We have a little of a language barrier, but he definitely doesn't seem like a hack. When I told him we wanted two showerheads one rainshower and one sliding bar, he asked if I wanted it like the last bathroom he did and showed me the attached pic. Uhhh no, too fancy for us *lol*. I am going to continue to agonize about this for the next couple day's and drive DH crazy. It's hard to put it off, because DH used it as his paint room and didn't clean up. Previous owner smoked in the house for 20 years, we had to prime and paint every single surface. Ripped out all the laminate and carpet and put in hardwood throughout. Here is a link that might be useful:

Too many lights pointing up at the walls of the house, and not enough lighting the path, marking the end of the drive, and showing off the branching in that big tree. Put the garage lights (marked in pink) on a motion detector so they turn on when you arrive. Four "locator" lights: the end of the drive, the start of the walk, and on either side of the steps. Change the uplight on the big tree into a downlight as high in the tree as you can get it. And add another uplight on the smaller tree. https://www.amplighting.com/led-downlights-moonlights/c/5