grow your wiki
The sandbox pattern involves creating a page, often called a sandbox, and encouraging others to practice wiki editing on this page. Problems that may result from this are:
Look for a page with the title "Sandbox" or something similar, or a description telling people to use it as a place to practice wiki editing. Or you might notice if users have very limited permissions by default, and only get permission to edit more content once they have "graduated" and proven themselves worthy.
Use the associated comments or discussion section of the page to propose deleting it, and gently encourage people to directly edit pages containing real content. Since edits can be changed as often as needed, and mistakes can be easily fixed there is virtually no risk in giving beginners free rein.