Fix Sidebar Length to Post Length

In the Widgets section for “Sidebar Blog” I add many “Text” widgets with ad code. I add many so ads can show for the entire sidebar length. The problem is that if the post is shorter, the sidebar keeps scrolling down to show all remaining widgets leaving a bunch of empty blank white space at the end of the post.

Is there anyway to set the sidebar to end at the end of the post content despite there being more widgets to show?

Thanks,