Because Phoenix is in the far southwestern part of the United States, you'll most likely encounter Bermuda grass growing in lawns. Bermuda is a warm-season grass that loves heat and is drought tolerant. When summer heat wanes to cooler winter temperatures, overseed Bermuda grass lawn with winter ryegrass. This allows the lawn to retain its green color throughout the winter since Bermuda naturally goes dormant during the cooler months.
Mow the Bermuda grass as short as possible without damaging the grass or turf, leaving about 1/2 inch of blade. Cut the amount of irrigation in half. Withhold fertilizing four to six weeks before overseeding.
Fill a broadcast spreader with the perennial ryegrass seed. Set the dial on the broadcast spreader to a rate of 8 to 10 lbs. per 1,000 sq ft.
Walk parallel paths over the entire yard and broadcast the grass seed.
Spread a light coating of sand over the entire yard. The depth should be 1/8-inch to 1/4-inch.
Set up lawn sprinklers and irrigate 1/4 of an inch to 1/2 of an inch of water over the entire yard. Water lightly two to four times per day after that to keep the soil moist.
Reduce the watering slowly after germination. Mow the ryegrass at 1-1/2 inches once it reaches 2 inches in height. Follow a normal irrigation schedule after the first mowing.