Dover, DE Frost Dates
Average frost dates, USDA hardiness zone, and growing season length for Dover, Delaware.
Gardening in Dover
Delaware's capital is small-town Mid-Atlantic, surrounded by the farmland that makes Delmarva one of the East Coast's most productive agricultural regions.
Zone 7a with 206 frost-free days. The Delaware Bay influence provides maritime moderation. The Coastal Plain soil is sandy and well-drained — easier to work than the Piedmont clay to the north.
Dover's agricultural heritage shows up in the surrounding poultry and produce farms. The state's small size means even the capital city is never far from working farmland.
What This Means for Dover Gardeners
The average last spring frost in Dover is around April 5, and the average first fall frost arrives around October 28. That gives you approximately 206 frost-free days to work with.
That's a generous season. You have time for full-size tomatoes, long-season peppers, and even watermelons without the anxiety of racing the frost. Start warm-season seeds indoors 6-8 weeks before your last frost to hit the ground running. Fall planting is your second opportunity — garlic, kale, lettuce, and broccoli all go in 8-10 weeks before your first frost for harvest into late autumn.
These dates are based on NOAA 30-year Climate Normal data for the Dover area. Your actual frost dates could shift 2-3 weeks in either direction in any given year. Learn more about our data sources.
What to Grow in Dover
Dover's 206-day growing season is generous — long enough for two full growing windows (spring and fall) with warm-season crops between them. You can grow the full range of vegetables, herbs, and flowers with proper timing. Focus on heat-tolerant varieties for midsummer and cool-season crops for extended fall harvests. Recommended starting points: tomatoes, peppers, beans, cucumbers, squash, garlic, kale, and sunflowers.
See the full Delaware planting guide for all 40 plants: Delaware Planting Calendar. Or enter your zip code for exact planting dates personalized to Dover.
More About Zone 7A
Dover is in USDA Hardiness Zone 7A, which means average annual extreme minimum temperatures between 0°F to 5°F. View the full Zone 7A planting guide.
See the complete planting calendar for Delaware: Delaware Planting Calendar.
Other Cities in Delaware
Frequently Asked Questions
These dates are based on NOAA's 30-year Climate Normal data for the Dover area. They represent historical averages, not predictions. In any given year, the actual last frost could be 2-3 weeks earlier or later. Microclimates within Dover (urban heat islands, hilltops, low-lying valleys) can also shift your local frost dates by a week or more.
Cool-season crops go in 3-4 weeks before your last frost (April 5). Warm-season crops wait until 2 weeks after. You have time for a fall round too — plant cool-season crops again in late summer for harvest into autumn. Enter your zip code for exact dates.