Both the grapevine (the unofficial communication channels of your ministry) and meetings (the official communication channels of your ministry) are
necessary and have their pros and cons.

The grapevine is faster and better listened to.
The grapevine loses context—in the repetition of details, some are dropped and some are embellished
Encourage your staff to think of the grapevine as just part of the story—there is almost always more to the story.
A healthy grapevine passes on helpful information and encouragement. A toxic grapevine is the main channel for gossip and rumors. Root out the toxic grapevine by addressing the individual who starts and repeats harmful words.
Ask about the grapevine—identify a couple of people who you believe to be well connected and ask them what is out there.
Feed both the grapevine and the meetings; they both need information—the more critical and complex should be reserved for meetings, but good news is one of the best things to pass through the grapevine.