Arizona's low desert — Phoenix, Tucson, the whole Sonoran sprawl — runs the most distinctive lawn calendar in the country, built around a two-grass system most of the rest of the nation never deals with. Bermudagrass is the summer lawn: it loves the brutal desert heat and goes dormant and tan in the mild winter. Because nobody wants a brown lawn through Arizona's beautiful winter, the tradition is to overseed perennial ryegrass over the dormant Bermuda each fall, giving you a green winter lawn, then transition back to Bermuda in late spring. That double-grass cycle drives everything.
Heat and water dominate the rest. A Phoenix summer means weeks over 110°F, where even Bermuda needs daily deep watering to survive, and water is genuinely scarce and expensive across the state. Many cities and HOAs have watering guidance and rising water costs that make efficient irrigation non-negotiable — a smart controller that waters in the pre-dawn cool and skips the rare rain is one of the best investments an Arizona lawn owner can make. The higher elevations around Flagstaff and the White Mountains are a different world — cool enough for cool-season grass — but the iconic Arizona lawn challenge is the low-desert Bermuda-and-ryegrass cycle.
The two pivot points are the fall overseed and the spring transition. In October you scalp the Bermuda down hard, rake out the clippings, and broadcast perennial ryegrass for a winter lawn. In April or May, as the heat returns, you stop watering and mowing the ryegrass so it dies back and let the Bermuda take over again. Get those two transitions right and the Arizona lawn runs smoothly; botch the timing and you get a patchy, stressed mess in the worst heat of the year.
Compare similar calendar patterns
Arizona is in the warm-season south group. These states follow similar seasonal logic, though local soil, elevation, and weather still matter.
Calendars are general regional guidance for The Lawn Report. Local microclimates, soil, and current weather always come first.