CreeperHeal is a plugin for Spigot, a Minecraft server implementation. It is available on the Spigot forums.

The objective of the plugin is to keep Creepers interesting while protecting your precious buildings and your pristine landscape. Creepers explode and cause as much damage as usual, but after a while, the explosion starts to heal, little by little. If you come around 5 minutes later, you wouldn't know a Creeper was there!

CreeperHeal supports all kinds of explosions (including from other plugins), as well as fire, and griefing prevention.

For more details, see the Spigot project page, the Wiki, or the javadoc.