Peas are one of the garden's most popular late winter/early spring crops. The last frost date for Redmond, WA, is approximately March 16th. Peas can be planted four to six weeks before the last frost date. Keep in mind that peas germinate best between 40 and 70 degrees. In cold soil, your peas will germinate slowly. Peas planted later, in 60-degree soil, will catch up in no time. Peas can take a light frost, but several days of freezing temperatures will damage new shoots. A light frost blanket is a great idea.
The three most popular pea varieties are:
Sweet peas, aka garden peas or English peas (Pisum sativum ssp. sativum), have inedible pods from which the seeds (peas) are taken.
Snow peas (P. sativum var. macrocarpon) produce edible, flat, stringless pods containing small peas.
Snap peas (P. sativum var. macrocarpon ser. cv.) produce thick, edible pods containing large/full-size peas.
Peas are legumes, and they fix nitrogen. When pleas are planted in the ground, there is no need for additional fertilizer. Peas are, however, susceptible to the pea weevil. See this publication from WSU for more detailed information.
Also, the podcast "You Bet Your Garden" just had an episode about peas, if anyone is interested...
Thank you for the date info! I'm going to be planting sugar snap peas myself. :)