Green Bay, Wisconsin planting calendar and frost dates
Green Bay is in USDA hardiness zone 5b. The last spring frost typically comes around April 30 and the first fall frost around October 9, giving about 161 frost-free days a year.
- Hardiness zone
- Zone 5b
- Typical last frost
- April 30
- Typical first frost
- October 9
- Frost-free season
- 161 days
Frost dates in Green Bay
Last spring frost
- April 16Risky: frost later than this in 9 years out of 10
- April 30Typical: a later frost in half of years
- May 16Safe: a later frost only 1 year in 10
First fall frost
- September 24Risky: frost earlier than this 1 year in 10
- October 9Typical: an earlier frost in half of years
- October 26Late: frost before this in 9 years out of 10
The growing season between the typical last and first frosts is about 161 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 17 and returns around October 24.
NOAA U.S. Climate Normals 1991-2020 for Green Bay, 4.7 miles WSW of the city center. 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 Green Bay
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: black-eyed susans, blueberries, garlic, grapes, grass seed, hollyhocks, kale, onions, peas, poppies, raspberries, rhubarb, strawberries, turnips, wildflowers
April
Start indoors: basil, cantaloupes, celery, cilantro, cosmos, cucumbers, eggplants, marigolds, nasturtiums, okra, peppers, pumpkins, ranunculus, tomatoes, watermelons, winter squash, zucchini
Plant or sow outdoors: asparagus, beets, black-eyed susans, blackberries, blueberries, broccoli, cabbages, carrots, cauliflower, chives, cilantro, collard greens, dahlias, dill, figs, garden mums, garlic, gladioli, grapes, grass seed, green onions, hollyhocks, kale, lavenders, leeks, lettuce, lilies, marigolds, mints, nasturtiums, onions, oregano, parsley, peas, petunias, poppies, potatoes, radishes, ranunculus, raspberries, rhubarb, rosemary, roses, sage, snapdragons, spinach, strawberries, sunflowers, sweet corn, swiss chard, thyme, turnips, wildflowers
May
Start indoors: cantaloupes, cosmos, cucumbers, okra, pumpkins, watermelons, winter squash, 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, potatoes, pumpkins, ranunculus, rosemary, sage, spinach, sunflowers, sweet corn, sweet peas, swiss chard, tall fescue, thyme, tomatoes, watermelons, winter squash, zucchini
June
Start indoors: zinnias
Plant or sow outdoors: asparagus, basil, bermudagrass, cantaloupes, celery, centipedegrass, cosmos, cucumbers, eggplants, green beans, green onions, okra, peanuts, peppers, pumpkins, st. augustinegrass, sweet potatoes, tomatoes, watermelons, winter squash, zoysiagrass, zucchini
July
Plant or sow outdoors: bermudagrass, centipedegrass, green onions, okra, st. augustinegrass, zinnias, zoysiagrass
Plant for fall: bearded irises, beets, broccoli, brussels sprouts, cabbages, carrots, cauliflower, collard greens, lettuce, peas, radishes, snapdragons, spinach, swiss chard, turnips
August
Plant for fall: azaleas, bearded irises, beets, broccoli, cabbages, carrots, cauliflower, clematis, coneflowers, crocuses, daffodils, daylilies, grass seed, hostas, hydrangeas, kale, lettuce, lilies, ornamental alliums, peonies, radishes, roses, saffron, snapdragons, spinach, swiss chard, tulips, turnips
September
Plant for fall: cabbages, cauliflower, crocuses, daffodils, daylilies, grass seed, hostas, hyacinths, kale, lilies, ornamental alliums, peonies, radishes, saffron, spinach, tulips
October
Plant for fall: crocuses, daffodils, garlic, hyacinths, lilies, ornamental alliums, peonies, tulips
Frost dates and zones by ZIP code in Green Bay
All 7 of Green Bay's main ZIP codes take their frost dates from Green Bay, so the dates on this page apply across the city. Every one of them is in zone 5b.
| ZIP code | Zone | Weather station | Typical last frost | Typical first frost |
|---|---|---|---|---|
| 54229 | 5b | Green Bay, 4.7 mi WSW | Apr 30 | Oct 9 |
| 54301 | 5b | Green Bay, 4.7 mi WSW | Apr 30 | Oct 9 |
| 54302 | 5b | Green Bay, 4.7 mi WSW | Apr 30 | Oct 9 |
| 54303 | 5b | Green Bay, 4.7 mi WSW | Apr 30 | Oct 9 |
| 54304 | 5b | Green Bay, 4.7 mi WSW | Apr 30 | Oct 9 |
| 54311 | 5b | Green Bay, 4.7 mi WSW | Apr 30 | Oct 9 |
| 54313 | 5b | Green Bay, 4.7 mi WSW | Apr 30 | Oct 9 |
Planting dates for popular crops in Green Bay
| Plant | Start indoors | Plant or sow outdoors | Fall planting |
|---|---|---|---|
| Tomatoes | Mar 31 to Apr 14 | May 26 to Jun 9 | — |
| Strawberries | — | Mar 19 to Apr 2 | — |
| Lettuce | Mar 5 to 19 | Apr 23 to May 7 | Jul 10 to Aug 14 |
| Cilantro | Mar 19 to Apr 2 | Apr 30 to May 7 | — |
| Basil | Apr 7 to 21 | May 26 to Jun 2 | — |
| Potatoes | — | Apr 30 to May 7 | — |
| Garlic | — | Mar 19 to Apr 2 | Oct 9 to 23 |
| Onions | Jan 8 to Feb 19 | Apr 2 to 16 | — |
| Cucumbers | Apr 28 to May 12 | May 26 to Jun 9 | — |
| Pumpkins | Apr 28 to May 12 | May 26 to Jun 9 | — |
| Peppers | Mar 10 to Apr 7 | May 26 to Jun 9 | — |
| Carrots | — | Apr 9 to 30 | Jul 17 to Aug 7 |
| Sweet Potatoes | — | Jun 10 to 17 | — |
| Watermelons | Apr 21 to May 5 | May 26 to Jun 9 | — |
| Sweet Corn | — | Apr 30 to May 14 | — |
| Green Beans | — | May 26 to Jun 9 | — |
| Zucchini | Apr 28 to May 12 | May 26 to Jun 9 | — |
| Broccoli | Feb 12 to Mar 5 | Apr 2 to 16 | Jul 24 to Aug 21 |
| Peas | — | Mar 19 to Apr 2 | Jul 17 to 31 |
| Spinach | Mar 19 to 26 | Apr 23 to May 7 | Jul 31 to Sep 4 |
| Sunflowers | — | Apr 30 to May 21 | — |
| Zinnias | Jun 6 to 13 | Jul 4 to 18 | — |
| Tulips | — | — | Aug 28 to Oct 23 |
| Daffodils | — | — | Aug 28 to Oct 9 |
| Grass Seed | — | Mar 19 to Apr 2 | Aug 28 to Sep 11 |
Nearby cities
- Appleton, WI zone 5b, last frost May 4
- Oshkosh, WI zone 5b, last frost Apr 24
- Milwaukee, WI zone 5b, last frost Apr 19
- West Allis, WI zone 5b, last frost Apr 19
- Waukesha, WI zone 5b, last frost May 1
- Madison, WI zone 5b, last frost May 1
Planting in WisconsinAbout zone 5bPrintable calendar for Green Bay
Questions
When is the last frost in Green Bay?
Around April 30 in a typical year, based on NOAA's 1991-2020 records for Green Bay. There is still a 1 in 10 chance of frost after May 16.
What planting zone is Green Bay in?
USDA hardiness zone 5b (2023 map). The zone tells you which perennials survive the winter; planting dates depend on frost dates instead.
When should I plant tomatoes in Green Bay?
Start seeds indoors March 31 to April 14 and set plants out May 26 to June 9.
When is the first frost in Green Bay?
Around October 9 in a typical year, and before September 24 about 1 year in 10.