They will plant pre-germinated seed into the parts of the court that need it. They've been experimenting with this technique for at least 2 years, and had to prove it's efficacy. The only thing that could have hurt them was the Championships not finishing on time. That's no longer an issue.
Pre-germinated seeds are basically grass seeds that already have 4 days or so growth. They need that to be done because they only have 20 days between the tournaments and grass normally takes a bit longer to grow properly and then cut to proper playing height.
Here's one of the many articles