The earliest of our spring wildflowers usually begin blooming here in Tucson in mid to late February. Our spring wildflowers usually last until sometime in May when hot weather arrives.
Tuber Anemone (Anemone tuberosa) is an early spring wildflower that usually begins blooming here in Tucson in February.
Our spring wildflowers are very dependent on the weather and winter rainfall. There were almost no spring wildflowers (except in irrigated areas) in the spring of 2006 after an abnormally warm and rainless winter. The winter of 2006/2007 is colder and we have had a bit of rain and even a little snow, so we will probably have at least some wildflowers this spring.
Tucson is not known for large scale wildflower displays where the hills and valleys are carpeted with one or more species of wildflowers, such as can be seen in California's Antelope Valley, instead the desert around Tucson has a great diversity of wildflowers, almost like a botanical garden.
My favorite spring wildflower hikes in the Tucson area are the wide and fairly easy 50-Year Trail in Catalina State Park and the Sweetwater Trail in the Tucson Mountains. If you want to see a large scale spring wildflower display, Picacho Peak State Park located 40 miles (64 km) north of Tucson will have fields of California Poppies (Eschscholzia californica ssp. mexicana) carpeting the ground in the spring after sufficient winter rains.
To check the current spring wildflower conditions once the season begins in Arizona State Parks, you can either visit the individual State Parks websites or check their current press releases (yes, they have spring wildflower press releases if there are wildflowers).