- 1). Dig a 6-inch hole in your lawn to test the soil's pH range. St. Augustine grass grows within a range of 5 to 8.5, while Bermuda grass grows within a range of 6.5 to 8. If your St. Augustine grass is not growing within its range it will result in a weak root system which will allow other grassy weeds to move in. Spread lime over acidic soil and sulfur over alkaline soil.
- 2). Walk around your lawn area to locate your Bermuda grass. Bermuda grass has hairy leaf sheaths and multiple leaf nodes. St. Augustine grass has overlapping leaf sheaths that are compressed and smooth. Sprinkle colored chalk around the areas where your Bermuda grass is growing.
- 3). Wet your Bermuda grass areas. Press a shovel 6 inches into the ground and lift the grass up by its roots. Throw away or burn the Bermuda grass debris. Till the bald areas.
- 4). Broadcast your St. Augustine grass by hand over the bald areas. For large areas, use 1/3 lb. of grass seed for every 1,000 square feet. Cover the seed with 1/4 inch of compost. Water the soil, so that the ground is moist but not saturated.
- 5). Water your bald spots four times a day, starting in the morning and ending in the afternoon to help your grass seed to germinate.
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