Tempting frost

According to Cornell's map (which is great if you live in NY like me) Our final expected frost date is somewhere between april 10 and 30th (we live on the boarder between two areas). Last year the spring crops went in the ground on the 21st. Though I had a bit of a frost scare, everything pulled through. One of the problems I found with the time table I used last year was that some seedlings were a bit small, and some which I know are cold tolerant tended to take a long time to mature and were holding up the succession plan.

Since I have a new bed I will be working with I am going to try an experiment. I am still determined to grow corn, but I know I have to get it in the ground long before july 7th which is when it went in last year. I figure between 70-80 days should be enough to get a decent yeild from a pea variety rated at 65 days. Cornell rates mid may as optimum planting time in accordance with IPM. This means the peas would have to go in mid march. On more than one occasion I have heard people suggest planting peas on st. patrick's day, which is of course mid march. The problem is, I don't remember a st. patty's day in syracuse where I have not sputtered some inappropriate metaphor about the cold. What the heck! lets do it! Its so crazy it might work, and I have seen fall planted pea vines shrug of frost and even a dusting of snow. My concern is germination. I'm thinking a floating row cover or makeshift cold frame to protect the seedlings, but will they germinate without outside help? do I put some peas in flats for a week, and then pop them in the ground once they sprout?

I'd like to do a similar think with the potatoes though not as radical. Last season I followed the potatoes with bush beans and I'd like to do so again, but the beans had just started producing when they were frost killed. A week or two sooner (say Aug 1) to get the potatoes out and the beans in would probably give me a full crop. Since last year I dug the first new potatoes on the 29th of July and the last full sized Aug 13, it seems feasible if memory serves that so long as they get to me in time, It should be warm enough and safe to plant by April 15th or so, roughly two weeks earlier.