How to Grow Bahia Sod Under an Oak Tree

Trim your oak tree. Thin out thick growth to ensure an adequate amount of sunlight reaches the soil beneath the canopy. Use a branch saw to remove the lower branches to a height of 6 to 8 feet. Cut the branches off near their point of insertion. Thin out any crowded overhead branches to create an open canopy that provides partially sunny conditions.

Remove any existing vegetation growing in the soil beneath your oak tree. Pull the plants or weeds by hand to avoid damaging the oak's underlying root system.

Test the soil beneath your oak tree. Use a soil test kit to determine the health of your soil. The roots of large oak trees tend to deplete the soil of nutrients. Follow the instructions on the test results to incorporate missing nutrients into the soil over your tree's roots.

Spread a 2-inch layer of vegetative compost over the surface of the soil. Work this amendment into the top 3 to 4 inches of soil surrounding your oak tree. Use a small hand rake to dig around the roots of your oak tree. Avoid scraping or gouging the roots near the surface of the soil.

Spray a fine mist of water over the soil with a garden hose and sprayer attachment. Create an even dampness over the prepared site. Start laying your pieces of Bahia sod along the outer perimeter of your oak tree, working your way toward the trunk. Use an old knife to trim the edges of the sod to fit your planting site. Avoid covering exposed roots near the base of your tree by cutting the pieces to fit around the roots. Water your new sod after planting. Keep the soil slightly moist near the bottom of the grass roots.

Fertilize your Bahia grass in the spring and early summer. Bahia grass is susceptible to iron deficiency, a condition that causes the blades to turn yellow. Apply a time-release fertilizer that contains iron. The time-release granules slowly dissolve, supplying a continual and gradual release of nutrients, an important consideration when growing Bahia grass over tree roots. Bahia grass is susceptible to iron deficiency, a condition that causes the blades to turn yellow.