St. Augustine grass originates from tropical regions, particularly sandy areas by bodies of water, such as beaches, marshes, limestone shorelines and swamps. It grows well in a wide range of soil types as long as there is good drainage.
St. Augustine grass that grows in sandy soils requires more frequent watering and more intense fertilization. It needs about 3/4 inch of water every three or four days, and fertilizer at a rate of one pound of nitrogen per 1,000 square feet every month during the growing season.
St. Augustine grass growing in sandy soil faces more problems from nematodes, which are microscopic worms that attack the roots. Nematodes turn the grass yellow and eventually kill it. Chemical nematicide can effectively kill nematodes.