There is no such method in the Docking control. What I would suggest you is to enumerate all the panes and set their IsHiddent property to true (if you want to close them) or to call their RemoveFromParent method (if you want to destroy them). Here is an example of what I mean:
// to hide the pane
//pane.RemoveFromParent(); to destroy the pane
Hope this helps.
the Telerik team
Do you want to have your say when we set our development plans?
Do you want to know when a feature you care about is added or when a bug fixed?
Telerik Public Issue Tracking
system and vote to affect the priority of the items.