This depends entirely on how strong of a feeder the female is after she lays, how big the clutch weighs and how big she was before she laid the eggs. Some girls don't want to eat much after they lay, and they take months and months to get back up to breeding size. Other girls will be back to their pre-lay weight or bigger within a month or two.
Personally, I like to give them at least 6 months to recover and grow. But, sometimes females have something else in mind and 3 months after they lay eggs, they are ready to ovulate again. That is where an ultrasound comes in handy. I don't like the idea of clutches that close together, but there seems to be less risk of binding if the eggs get fertilized.
The most important thing is not time, but size. Just make sure that the girl is as big or bigger than she was before she last laid, and give her as much time as she wants.