Boyce Thompson Arboretum is a definite must see near Phoenix. For those who have yet to make the trip, I would recommend going now-ish. The arboretum is great to visit in the spring and summer (though it might be a bit warm!). Not only does the arboretum contain a great diversity of plant life, but it also attracts a large number of animals, especially birds, especially during spring migration.
I recently went to Boyd Thompson with my mom when she visited. We had some weird weather (cold and rainy) but still saw a lot of cool animals and enjoyed many spring flowers.
The cool thing about Boyce Thompson, is that it has more than just a Sonoran desert environment, which is still awesome by the way! There is a Chihuahuan desert area, an Australian area – complete with a eucalyptus forest! – a Sonoran desert riparian area, and a South American area. Here are a few images of some of the environments you can visit:
The hummingbird garden was also fun to visit, especially now, as you can see several species of hummingbird there. Here is a picture of a broad-billed hummingbird, which is typically only found in Arizona and Mexico.
There is also the demonstration garden, which has many different plants arranged to fit different garden plans/types. There were lots of things flowering while we was there, and I was able to get some pretty awesome bird photos.
The best moment was when a northern cardinal got within a few feet of me and let me take some really up close photos. Here is the best one!
Again, I would highly recommend visiting this place; you will see amazing things and learn a great deal about plant diversity and natural history!