Growing grass under trees can pose a challenge. Tree branches shade out the sun that most grass species need to thrive. Tree roots compete with grass for water and nutrients in the soil. The easiest way to overcome this problem is to install mulch or a shade-loving groundcover under the tree. However, if you are determined to grow grass under trees, it is possible to achieve your goal by following a few careful preparations.
Prune lower branches from the tree or trees you want to grow grass under. Prune them high enough so you can comfortably walk upright under the tree canopy.
Select a shade-tolerant cultivar of grass. Fescues are the most shade tolerant and can be grown in locations that are shaded, as long as they have access to bright light.
Rough up the soil with a garden rake and sow the fescue grass seeds in the soil at a rate of 6 to 8 lbs. per 1,000 square feet. Rake the seeds into the top layer of soil.
Water your seeds daily for 14 to 21 days or until complete germination has taken place. Slowly reduce watering until you are watering once or twice a week. Apply 1 inch of water at each of these waterings.
Fertilize the grass with 1 lb of nitrogen per 1,000 square feet two to three times per year. Apply the first application in early spring and another one in fall. Do another application in late spring, if desired.
Mow your grass high in shady conditions. Ideally, you should mow your grass between 2 1/2 and 3 1/2 inches high to allow as much surface area as possible for photosynthesis.