Sidebar Navigation menu overlaps with other widgets

If I create a Custom Menu and put it at the top of the sidebar. Any other widgets I put below it are overlaped by the Custom Menu (see attached). It’s almost like the container isn’t expanding based on the number of entries in the menu.

You can see it in action here: http://thequantumawakening.com/wordpress/index.php/home-2/

I won’t be leaving it up too long but we haven’t published quite yet anyway.

Thanks.