With the growing season about to begin, the National Weather Service office in Albany, N.Y., will be issuing freeze warnings during the spring when the overnight temperature is forecast to be 32 degrees or lower, and frost warnings when the temperatures are forecast to be between 33 and 36 degrees.
Based on weather data from the period between 1971 and 2000, the Weather Service has set May 15 as the start of the growing season in the Connecticut River Valley, and May 25 for higher elevation locations in Windham County.
The Weather Service advises that these dates are a rough estimate, and may not indicate the specific date for the end of frost and freeze threats for a specific location.
In early May last year, a hard freeze struck and caused crop damage for orchards and fruit growers around Vermont.
According to the University of Vermont Extension, tender transplants like tomatoes, eggplants, and peppers may not survive if set out too early, and they usually don't grow very fast if conditions are cool. Pumpkins, squash, melons, and many other vegetables and flowers also are sensitive to frost. In most locations in Vermont, the general rule is to wait until late May or early June to plant these in your garden.
As for onions, peas, lettuce, carrots, root crops (carrots, turnips, beets), and hardy herbs, they can be planted in early to mid May. So can Cole crops - such as broccoli, cabbage, cauliflower, and Brussels sprouts - although the Extension advises to be sure to harden these seedlings off before moving them into the garden.