And here I sit eating fresh peas (indeterminate) from June through August from seeds directly sowed mid-February through April. I'm thinking about trying a later planting for fall harvest.
In borderline situations, choosing the right variety helps. I can get away with growing sweet corn by selecting the varieties with the shortest time to maturity which make small ears (<8" long) and cross my fingers that May is warm enough to germinate them. They're never "knee-high-by-the-fourth-of-July", but they do mature by early September. On the other hand, the sickly feed corn they grow for Tillamook dairies an hour's drive south of me makes me shudder because they plant it May 1, whether the weather is ready or not!