Re-seeding lawn over a newly planted winter grass in warm climate

Question

We recently had our septic system replaced about a month ago (in December). I live in Florida, and according to the local code, I had to get grass growing over the drain field by March ("mound stabilization"), when the final inspection will occur. I chose to seed rye grass in the dirt over the mound, which grows well in Florida winters, and is coming in nicely--so hopefully should pass inspection.

However, here in Florida, by late February or early March, the weather will start turning warmer again, so I'd like to go ahead and get some permanent summer grass started within another 4-6 weeks. I'd like to seed something like Bermudagrass at that point. Are there any special considerations I need when seeding new grass over a temporary/winter lawn like this, to ensure it comes in well? The rye grass is fairly thin, so for example, it might be easy to lightly rake in the Bermuda seed once I've spread it. Or should I just wait until the rye starts to die out from the summer heat?

Answer 1

Bermuda grass needs constant soil temperature of 65°F or higher to germinate and grow well. If the soil temperature drops after it has germinated the grass seed may fail to survive.
I don't know enough about your local soil temperatures to tell you when to plant Bermuda grass, but I think you will have to wait until mid spring at earliest. I suggest using a thermometer to check the soil temperature, at least a depth of 2". Once the soil has stayed above 65 for a week then you should feel safe to plant Bermuda grass.

Planting Bermuda Grass

Germination of Bermuda Grass SFGate