The fact that you fenced the land into your garden means that you have the makings of a case. You would also need to show that you have used the land as your own. If, for example, you have built a shed on the land and maintained the plants and/or lawn, that will help. Importantly, you must not have been given the owner’s consent to use the land. If you want to make an application for registration of the land, you should speak to a lawyer first to get specific advice about the strength of your case and the process involved.