Waterbury, Connecticut planting calendar and frost dates
Waterbury is in USDA hardiness zone 6b. The last spring frost typically comes around April 26 and the first fall frost around October 16, giving about 175 frost-free days a year.
- Hardiness zone
- Zone 6b
- Typical last frost
- April 26
- Typical first frost
- October 16
- Frost-free season
- 175 days
Frost dates in Waterbury
Last spring frost
- April 11Risky: frost later than this in 9 years out of 10
- April 26Typical: a later frost in half of years
- May 9Safe: a later frost only 1 year in 10
First fall frost
- October 4Risky: frost earlier than this 1 year in 10
- October 16Typical: an earlier frost in half of years
- November 1Late: frost before this in 9 years out of 10
The growing season between the typical last and first frosts is about 175 days. Frost here means a low of 32°F at the weather station. A hard freeze (28°F), which damages most hardy crops too, typically ends around April 10 and returns around October 30.
NOAA U.S. Climate Normals 1991-2020 for Meriden Markham Muni Airport, 12 miles ESE of the city center and 168 feet lower. Low-lying and rural spots often frost later in spring and earlier in fall than airports and city centers.
What to plant each month in Waterbury
January
Start indoors: onions
February
Start indoors: broccoli, cabbages, cauliflower, collard greens, kale, leeks, onions, oregano, parsley, petunias, ranunculus, rosemary, snapdragons
March
Start indoors: black-eyed susans, broccoli, cabbages, cauliflower, celery, chives, cilantro, collard greens, eggplants, ginger, leeks, lettuce, marigolds, nasturtiums, oregano, parsley, peppers, petunias, ranunculus, rosemary, sage, snapdragons, spinach, swiss chard, tomatoes
Plant or sow outdoors: beets, black-eyed susans, blackberries, blueberries, broccoli, cauliflower, chives, cilantro, collard greens, figs, garlic, gladioli, grapes, grass seed, hollyhocks, kale, leeks, onions, peas, poppies, radishes, ranunculus, raspberries, rhubarb, roses, spinach, strawberries, swiss chard, turnips, wildflowers
April
Start indoors: basil, cantaloupes, cosmos, cucumbers, eggplants, okra, peppers, pumpkins, ranunculus, tomatoes, watermelons, winter squash, zucchini
Plant or sow outdoors: asparagus, beets, black-eyed susans, blackberries, broccoli, cabbages, carrots, cauliflower, chives, cilantro, collard greens, dahlias, dill, figs, garden mums, gladioli, grapes, green onions, lavenders, leeks, lettuce, lilies, marigolds, mints, nasturtiums, onions, oregano, parsley, petunias, potatoes, radishes, ranunculus, rosemary, roses, sage, snapdragons, spinach, sunflowers, sweet corn, swiss chard, thyme, turnips
May
Start indoors: cosmos, cucumbers, okra, pumpkins, winter squash, zinnias, zucchini
Plant or sow outdoors: asparagus, basil, cantaloupes, chives, cilantro, cucumbers, dahlias, dill, eggplants, garden mums, ginger, gladioli, grapes, green beans, green onions, kentucky bluegrass, lavenders, lettuce, lilies, marigolds, mints, nasturtiums, oregano, parsley, peppers, perennial ryegrass, petunias, pumpkins, ranunculus, rosemary, sage, spinach, st. augustinegrass, sunflowers, sweet corn, sweet peas, swiss chard, tall fescue, thyme, tomatoes, watermelons, winter squash, zucchini
June
Start indoors: zinnias
Plant or sow outdoors: bermudagrass, cantaloupes, celery, centipedegrass, cosmos, cucumbers, eggplants, green beans, green onions, okra, peanuts, peppers, pumpkins, st. augustinegrass, sweet potatoes, tomatoes, watermelons, winter squash, zinnias, zoysiagrass, zucchini
July
Plant or sow outdoors: bermudagrass, centipedegrass, st. augustinegrass, zinnias, zoysiagrass
Plant for fall: bearded irises, broccoli, brussels sprouts, carrots, collard greens, lettuce, peas, snapdragons, swiss chard
August
Plant for fall: azaleas, bearded irises, beets, broccoli, cabbages, carrots, cauliflower, clematis, collard greens, coneflowers, daylilies, hostas, hydrangeas, kale, lettuce, peas, radishes, roses, saffron, snapdragons, spinach, swiss chard, turnips
September
Plant for fall: azaleas, bearded irises, cabbages, cauliflower, clematis, coneflowers, crocuses, daffodils, daylilies, grass seed, hostas, hyacinths, hydrangeas, kale, lilies, ornamental alliums, peonies, radishes, roses, saffron, spinach, tulips
October
Plant for fall: crocuses, daffodils, garlic, hyacinths, lilies, ornamental alliums, peonies, tulips
Frost dates and zones by ZIP code in Waterbury
All 5 of Waterbury's main ZIP codes take their frost dates from Meriden Markham Muni Airport, so the dates on this page apply across the city. Every one of them is in zone 6b.
| ZIP code | Zone | Weather station | Typical last frost | Typical first frost |
|---|---|---|---|---|
| 06704 | 6b | Meriden Markham Muni Airport, 12 mi ESE | Apr 26 | Oct 16 |
| 06705 | 6b | Meriden Markham Muni Airport, 12 mi ESE | Apr 26 | Oct 16 |
| 06706 | 6b | Meriden Markham Muni Airport, 12 mi ESE | Apr 26 | Oct 16 |
| 06708 | 6b | Meriden Markham Muni Airport, 12 mi ESE | Apr 26 | Oct 16 |
| 06710 | 6b | Meriden Markham Muni Airport, 12 mi ESE | Apr 26 | Oct 16 |
Meriden Markham Muni Airport also supplies the frost dates for Meriden, so their planting calendars match Waterbury's.
Planting dates for popular crops in Waterbury
| Plant | Start indoors | Plant or sow outdoors | Fall planting |
|---|---|---|---|
| Tomatoes | Mar 25 to Apr 8 | May 20 to Jun 3 | — |
| Strawberries | — | Mar 15 to 29 | — |
| Lettuce | Mar 1 to 15 | Apr 19 to May 3 | Jul 17 to Aug 21 |
| Cilantro | Mar 15 to 29 | Apr 26 to May 3 | — |
| Basil | Apr 1 to 15 | May 20 to 27 | — |
| Potatoes | — | Apr 19 to 26 | — |
| Garlic | — | Mar 15 to 29 | Oct 16 to 30 |
| Onions | Jan 4 to Feb 15 | Mar 29 to Apr 12 | — |
| Cucumbers | Apr 22 to May 6 | May 20 to Jun 3 | — |
| Pumpkins | Apr 22 to May 6 | May 20 to Jun 3 | — |
| Peppers | Mar 4 to Apr 1 | May 20 to Jun 3 | — |
| Carrots | — | Apr 5 to 26 | Jul 24 to Aug 14 |
| Sweet Potatoes | — | Jun 6 to 13 | — |
| Watermelons | Apr 15 to 29 | May 20 to Jun 3 | — |
| Sweet Corn | — | Apr 26 to May 10 | — |
| Green Beans | — | May 20 to Jun 3 | — |
| Zucchini | Apr 22 to May 6 | May 20 to Jun 3 | — |
| Broccoli | Feb 8 to Mar 1 | Mar 29 to Apr 12 | Jul 31 to Aug 28 |
| Peas | — | Mar 15 to 29 | Jul 24 to Aug 7 |
| Spinach | Mar 15 to 22 | Apr 19 to May 3 | Aug 7 to Sep 11 |
| Sunflowers | — | Apr 26 to May 17 | — |
| Zinnias | May 26 to Jun 2 | Jun 23 to Jul 7 | — |
| Tulips | — | — | Sep 4 to Oct 30 |
| Daffodils | — | — | Sep 4 to Oct 16 |
| Grass Seed | — | Mar 15 to 29 | Sep 4 to 18 |
Nearby cities
- Bristol, CT zone 6b, last frost Apr 25
- Meriden, CT zone 6b, last frost Apr 26
- New Britain, CT zone 6b, last frost Apr 17
- New Haven, CT zone 7a, last frost Apr 5
- West Haven, CT zone 7a, last frost Apr 17
- Milford city, CT zone 7a, last frost Apr 5
Planting in ConnecticutAbout zone 6bPrintable calendar for Waterbury
Questions
When is the last frost in Waterbury?
Around April 26 in a typical year, based on NOAA's 1991-2020 records for Meriden Markham Muni Airport. There is still a 1 in 10 chance of frost after May 9.
What planting zone is Waterbury in?
USDA hardiness zone 6b (2023 map). The zone tells you which perennials survive the winter; planting dates depend on frost dates instead.
When should I plant tomatoes in Waterbury?
Start seeds indoors March 25 to April 8 and set plants out May 20 to June 3.
When is the first frost in Waterbury?
Around October 16 in a typical year, and before October 4 about 1 year in 10.