Garlic mustard (see Sheila Rodger's photo at left) is also at its best time. With garlic mustard, my goal is definitely to kill it (and unfortunately for cooking demos, I think I succeeded last year - I don't have many rosettes of it out back this spring), but using it in February or March yields strong garlic flavor with less bitterness.

And then don't forget the winter annuals - chickweed, cuckooflower (another Sheila photo at left) - perhaps not at their largest yet, but definitely at a good stage for some "spring tonic", as the first greens of spring used to be called, back when lettuce wasn't a year-round staple at the grocery supercenter. Red sorrel, overwintering at ground level, can give some oxalic acid-punch before the rhubarb is up yet. Your wild garlic is out there now, just waiting to masquerade as the freshest chives.
I worry about sounding like a salesperson when I talk about weeds like this, and yes, if you want to find these plants and don't know what they look like, of course you could buy my latest book, and I'd be grateful. But whatever education you need is your own business: the weeds are out there, if not *in* your yard then close by, just waiting for you. No one is going to mind if you take them. Call it your own personal grocery self-checkout line, with no line.