The red-brick city at the center of town is also an impressive arboretum. It's true: 500 individual species make up a one-of-a-kind collection of desert and semi-desert trees, many of them very large. Among the flourishing exotics: a baobab and fever tree from Africa, calabashes and rock figs, boojums and, of course, the ever-amazing, winter-blooming floss silk tree south of the engineering building. UA has done a lot for Tucson gardening in general: Campus groundskeepers are highly trained and, like all UA staff, underpaid, which means that skillful landscape people are continually disseminating from there into the community. The arboretum's excellent Web site offers maps, suggested walks, tons of info and even a bloom update. And you thought it was all about red and blue petunias.
2. Tucson Botanical Gardens, 2150 N. Alvernon Way, 326-9686; www.tucsonbotanical.org
3. Tohono Chul Park, 7366 N. Paseo Del Norte, 575-8468; www.tohonochulpark.org