Treating Wood Furniture

Hi, everyone!
I just got a brand-new potting bench (yippee!!) which I believe is made of eucalyptus wood. It has a light stain with a red-brown color. What I'm wondering is should I oil it or otherwise treat it right away? And with what? I have a mahogany table that I've used teak oil on, but I have other stuff that I've done with spar varnish. The varnish might make for too much maintenance, I think. Plus wouldn't it keep my potting bench from weathering a little? I do want it to weather slightly to match my patio set, as they're next to each other. So my ultimate question, then, is should I wait until the bench fades a little before treating with teak oil (or something else), or should I do it now?

Thanks very much!