Command line to get VLC to play a folder?

I'm having a problem making a Nautilus action to play a folder in VLC. I can add the folder to the playlist no problem, recurse into subfolders and even play the first item. But how on earth do I clear the playlist first, so that at the next change of track I'm not taken back to what I was listening to before? There must be something obvious I'm missing?

For bonus points, how do I get my Nautilus action in the main context menu, not in the Actions sub-menu?

Ubuntu 15.04 and VLC 2.2