In Florida, lawns are often over-seeded with annual rye grass in fall. Florida lawns planted with warm-season grass are lush and green during the warm spring and summer. But, as the temperatures dip, many warm-season grasses go dormant and turn brown and unsightly. Rye grass is a cool-season grass. When planted on an existing warm-season lawn, it will provide color during the cooler fall and winter. The rye grass will die back in the spring when warm-season lawn grass comes to life again.
Rake your lawn to remove any loose debris on the surface.
Mow the lawn as low as your lawnmower's blades will go. Catch all of the clippings in your lawn mower's attached bag or rake them up after you have finished mowing. Do not mow St. Augustine grass lower than 3 inches.
Spread 10 lbs. of annual ryegrass per 1,000 square feet of lawn. Scatter half of the seed over the ground by hand while walking over the lawn in rows in one direction. Then spread the second half of the seed while walking in rows perpendicular to the first rows. For best coverage, use a mechanical seeder. Sow half the seed as you walk up and down the lawn, and the other half walking across the lawn in rows.
Sweep the grass with a stiff broom to help the seed penetrate through the grass and come into contact with the soil.
Water the freshly seeded lawn with 1 to 2 inches of water. Use the gentle spray from a hose or sprinkler system so you do not disturb the seed as it germinates. Keep the top few inches of the soil moist by watering once or twice daily until the seeds have germinated in seven to 10 days. Then, continue to water daily (using the same amount) for the next three weeks until the seedlings establish themselves. After that, reduce watering to an as-needed basis when the grass begins to show signs of wilting.
Repeat Steps 1 through 5, annually, in the fall.