Packages for the release of KDE SC 4.13 are available for Kubuntu 12.04LTS, 13.10 and our development release. You can get them from the Kubuntu Backports PPA. It includes an update of Plasma Desktop to 4.11.8.
To update, use the Software Repository Guide to add the following repository to your software sources list:
12.04LTS, 13.10:Or, from a command line: