My opinion is the first week of July. I always plant by the phase of the new moon coming. Depending on your weather, it will be approaching the hottest part of the summer. Make sure they get watered, but not to much to rot the seeds before they sprout. Running plants always take longer to grow than bush types. I live in N.C, my growing season goes till the end of Oct. sometimes longer. And I have planted peas as late as Aug.