Expect centipede grass to take 14 to 21 to germinate. Growing conditions and climate may alter that slightly.
Preferred germination rates of centipede grass seeds are in the range of 90 to 95 percent. The percentage comes from lab tests.
If the grass seed doesn't germinate as fast as expected, it may be because it is lacking the proper water dosage. Soaking the seeds will cause them to become water-logged and perhaps rot. They also can float away, causing gaps in a new lawn. Too little water can cause them to dry and die. Keep the soil moist to the touch but not wet.