In this video tutorial you can see how to use heal selection Gimp filter. It is filter from Resynthesizer suite of plugins which contains ten great useful filters. This filter saved me lot of time I hope it will do the same for you.
Before using heal selection you have to install Resynthesizer plugin. On this link you can find installation instructors and plugin files: http://registry.gimp.org/node/27986
Step 2: Extract the files from the zip.
For Windows users: Copy it to C:/users/”user-name”/.gimp-2.8/plugins.
For linux users: You can easily install with the package gimp-plugin-registry Install gimp-plugin-registry.
Command to install on terminal : sudo apt-get install gimp-plugin-registry
Step 4: Restart GIMP and changes will be updated.
Step 5: You can now, use Resynthesizer options from Filters>Enhance, Filters>Map and Filters>Render and choose the desired functionality like Heal Selection, Heal Transparency, Style, texture…