To have the most success with your PR team, you need to communicate with them.
This may seem like common sense when said out loud or written down, but then again, common sense isn't necessarily common.
Communication is critical to any successful communications program. The team needs to know what is going on with the company, products, customers, partners, leadership, etc. They need to be aware of both the positive and the potentially negative. Believe it or not, PR professionals are not mind readers nor can we create press coverage with a snap of our fingers.
To get the biggest bang for your buck on a positive announcement or to help prepare for any negative new cycles, the team needs to be given a heads up well in advance when possible. The whole "need to know basis" approach helps no one if your communications team isn't in the loop. Now, it doesn't have to be the whole PR team but at least someone from the team should be aware of what is going on.
Schedule weekly check-ins with your PR team to ensure that everyone is on the same page about hot topics, worry basket issues, the latest on product announcements, customers wins, etc. The more information the communications team has and the sooner it gets the details, the more prepared and successful they can be when it comes time to make an announcement.
Always be prepared. Always communicate with your PR team.