We often only have a 2-3 month growing season here - in 2018 the last frost/snow was June 26th and the first killing frost was the evening of September 3rd. I dearly hope not to see that short of a season again any time soon! Normally it is frost free mid June until the beginning of October. As a rule, we don't plant non-frost tolerant things out until the full moon in June. However, at that time it goes pretty much straight from freezing nights to hot drought, so we have no good season for spring-temp loving greens. I do have a small greenhouse outside where they will grow April - June to provide for us before the warm weather hits
They are all cold hardy varieties that can withstand lighter frosts or heavier frosts when under cover. Here we have to start early and grow under cover or we won't be able to grow much at all! I have had many successful years starting tomatoes in late February and peppers in March! Seems unconventional, but it does work 
