Bahia is a warm season grass, making April through June the best time to sow seed. This allows for a full growing season before cold weather arrives and takes advantage of the rainy season. Poor germination may be caused by too low temperatures (85 and above is optimal) or drying of the seeds in the soil. A ½ inch top-dressing of soil or weed-free hay over the seed is recommended to retain the moisture. When establishing any grass, it is important to irrigate more frequently than usual. A light watering two or three times a day may be necessary for two weeks to provide adequate moisture for seed germination. It is also important not to mow a newly established lawn until the roots have had a chance to work down into the soil and establish themselves. Also, purchasing scarified seed (mechanically treated to increase the germination rate) will noticeably enhance the germination percentage.

Additional Resource
http://edis.ifas.ufl.edu/LH006