While I agree that it could be calendula, it could also be a highly invasive plant called hound's tongue. It, too, has sticky, resinous leaves, and a very similar shape, especially in rosette stage. I'd keep an eye on that lil bugger if I were you, Jules... Hopefully, it is calendula- hound's tongue can be quiet a bear to eradicate.
Well behaved women rarely make history - Eleanor Roosevelt. tiny ad:
Greenhouse of the Future ebook - now free for a while