Hi! I'm late finding this thread, but I'm automatically drawn to anyone trying to grow in the desert!
I used to live in Tucson, and now live in Nevada. Same heat problem.
I do not have quality lights, so my only option is to do an indoor-outdoor grow, keeping them in under fluoros and CFL's at night, and taking them out every morning for the day. But that's ONLY in spring and fall--if you get over 85-90, you'll likely have problems, especially with any broad leafed strains--those with more Indica. If you notice the plants that adapt themselves to the desert, they have tiny little leaves for transpiration. Big leaves burn up.
Now, in early summer--say, Feb, March, April and May--even if it gets 90 mid-day, you can still get GREAT morning sun to augment your lights. You won't need to do this, of course, if you have good lights. You can just do an indoor grow all the way, and that sure sounds like heaven to me!
But in the later spring, you may have to "rest" any plants to put outdoors to sun during the middle of the day--they can actually take the heat okay--up to about 90 degrees--as long as you have them under some kind of shade cloth. I have a shadecloth enclosure I made with PVC pipe--cheap and easy, and I push them in there mid-day for a couple of hours, and mist the leaves, tops and bottoms.
Also, if you take them outside, be SURE to put them in white pots, or cover your black pots with white duct tape or spray them white. As the temps increase, you will have to insulate them. I put my vegging plants in 1 gallon pots and put those pots in garden carts that have a layer of gravel on the bottom, and water up to the top of the gravel so there is a bit of humidity around the plants. Then, crumble up newspaper wads and push them all around the pots, filling up the air spaces to offer more cooling for the roots. You NEVER want the roots to start cooking. So, keep them covered and protected outside.
It takes a LOT of work do utilize the sun here in the desert--whether it's the Mojave or the Sonoran. It's doable, but it's nearly a full-time job. If you can get a REAL grow room set up, with a/c, fans, good lights--you're far better off.
Now, come harvest time, you're going to really have a tougher time. We don't have to worry about mold, but everything in our part of the world petrifies in a few hours. If you try to hang buds to dry, they will be dry and crumbly in 8-12 hours, and will taste like hay. You will most definitely want to invest in a good humidifier for your grow room, or you'll have a truly nasty tasting harvest.
If I can answer any desert related questions, don't hesitate to PM me, ok?
I'm NOT an experienced grower, and what I know, I learned here and from experimenting with growing indoors/outdoors at the same time. Still, I've learned a lot about keeping cannabis alive in this demanding, harsh, arid climate.
Here's a link to my first desert grow journal--it may have some good tips if you decide to do an indoor-outdoor for the time being, until you get your grow room finished.
http://www.marijuanapassion.com/forum/showthread.php?t=40536
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