Be sure to read the instructions on the back of the packet of seeds if you have it. You're instinct is right- Peas do well in cooler weather. They will produce well for you up until about July 4th (when the weather turns hot)- then you'll want to plan on ripping them out and planting something in their place as they will crumble under the hot weather.

I am by no means an expert.. but when I grew them- I always put them out as soon as the ground was workable. With the weather we've had so far that will be probably in about a week or two...depending on the location of your plot.