Plant too early and the ground is cold; plant before the rain ends and you are likely to get flooded out; plant too late and it is already into the hot season when peppers will not blossom and tomatoes never flourish.
I always manage to plant a little too late and my stuff seems to be stunted until near late summer. In years past I have always tried to fit it in between other weekend activities. This year, as part of changing the pace of my activities overall, I think I shall definitely have more time to plant - I am thinking maybe the middle of April.
What I am going to plant? I am, as always, not sure. I have my seeds from when Bountiful Gardens went out of business, so there is a variety of things (mostly beans, I suspect) in there. I try corn every year and fail every year but I will keep trying, I suppose (I think my problem is always not enough water). Tomatoes as well (The Ravishing Mrs. TB always wants them and I can never seem to come through). And, as usual, something completely off the wall (like sorghum).
This is always the best time for gardening - right before it actually starts happening and everything is growing, at least in my mind.