Take a look at "Growing Your Own" a pub from Oregon State University

http://ir.library.oregonstate.edu/xmlui/handle/1957/21092

Planting dates are on page 7. Portland is in Region 2.

Here is a link that might be useful: Growing Your Own - from Oregon State University

I think a lot depends upon the weather. If it stays cool then the peas keep producing. One thing we do is dig a trench where the peas are going to be planted. Over the winter we put the kitchen compost into this trench and cover it with soil. Plant the seeds in this and you'll get an amazing crop. Happy New Year.

99% of PDX gardeners plant tomatoes by May; June requires patience (but is a good time) and July is too late for tomato planting.

IF spring 2013 returns to normal after some year's absence, peas would be largely through in June. Note that a tomato planting does not require much initial space; pull one pea plant or leave a 16" diameter void in your pea planting and overlap the crops by a month.

you have to feel out both tomatoes and peas.

i like to plant pea starts AND put pea seeds in soil as soon as there is a nice mild stretch in late feb/early march.

also, its not the worst thing in the world to pull out still producing pea plants. if they butt up against tomatoes, just yank them.

as for tomatoes, i don't bother growing from seed. i buy as big as possible plants (i get them from marbott's or freddies-- usually $4 or so for a #1 container) and plant them out at the first warm stretch starting mid/late may. if it gets to june before a warm stretch i'll put them in the first week or so.

if you get them in any earlier and they experience a bunch of 42 degree nights they will quit growing.

I intend to plant peas as well as this crazy italian heirloom summer squash that does best when grown on a trellis in the same spot. I'll just throw the squash seeds in around May 1st and count on cutting back the peas instead of tearing them out like I usually do. We'll see how badly I screw it up.