Upstate NY is a big place. Its a lot colder in Saranac Lake than it is in Cobleskill.
But I'd guess Memorial Day on average.

Try going into the US Department of Agriculture (USDA) website, that should tell you the exact zone and last frost date.

Call your county extension agent or a local master gardener. They can give you information about your specific growing season.

Bob47,

For US first and last frost dates, check out the Old Farmer's Almanac listing below:

http://www.almanac.com/garden/frostus.php

For Canadian first ans last frost dates, check out:

http://www.tdc.ca/canadian_frost_dates.htm

Remember, a floating row cover such as Reemay can protect against cold and light frosts!

Best of luck with your growing season,

-Plantenthusiast