Flint, Michigan planting calendar and frost dates
Flint is in USDA hardiness zone 6a. The last spring frost typically comes around May 6 and the first fall frost around October 10, giving about 155 frost-free days a year.
- Hardiness zone
- Zone 6a
- Typical last frost
- May 6
- Typical first frost
- October 10
- Frost-free season
- 155 days
Frost dates in Flint
Last spring frost
- April 21Risky: frost later than this in 9 years out of 10
- May 6Typical: a later frost in half of years
- May 23Safe: a later frost only 1 year in 10
First fall frost
- September 26Risky: frost earlier than this 1 year in 10
- October 10Typical: an earlier frost in half of years
- October 25Late: frost before this in 9 years out of 10
The growing season between the typical last and first frosts is about 155 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 26 and returns around October 23.
NOAA U.S. Climate Normals 1991-2020 for Flint Bishop International Airport, 3 miles SW 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 Flint
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, kale, 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, onions, peas, poppies, raspberries, rhubarb, strawberries, turnips, wildflowers
April
Start indoors: basil, cantaloupes, cilantro, cosmos, cucumbers, eggplants, marigolds, nasturtiums, okra, peppers, pumpkins, ranunculus, spinach, swiss chard, 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, garlic, gladioli, grapes, grass seed, green onions, hollyhocks, kale, leeks, lettuce, onions, parsley, peas, poppies, potatoes, radishes, ranunculus, raspberries, rhubarb, roses, snapdragons, spinach, strawberries, swiss chard, turnips, wildflowers
May
Start indoors: cantaloupes, cosmos, cucumbers, okra, pumpkins, watermelons, winter squash, zucchini
Plant or sow outdoors: asparagus, basil, beets, cantaloupes, carrots, chives, cilantro, cucumbers, dahlias, dill, eggplants, figs, garden mums, ginger, gladioli, grapes, green beans, green onions, kentucky bluegrass, lavenders, leeks, lettuce, lilies, marigolds, mints, nasturtiums, oregano, parsley, peppers, perennial ryegrass, petunias, potatoes, pumpkins, ranunculus, rosemary, roses, sage, snapdragons, 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, bermudagrass, cantaloupes, celery, centipedegrass, cosmos, cucumbers, eggplants, garden mums, 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, green onions, 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, crocuses, daffodils, daylilies, grass seed, hostas, hydrangeas, kale, lettuce, lilies, ornamental alliums, peas, 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 Flint
All 5 of Flint's main ZIP codes take their frost dates from Flint Bishop International Airport, so the dates on this page apply across the city. Every one of them is in zone 6a.
| ZIP code | Zone | Weather station | Typical last frost | Typical first frost |
|---|---|---|---|---|
| 48503 | 6a | Flint Bishop International Airport, 3 mi SW | May 6 | Oct 10 |
| 48504 | 6a | Flint Bishop International Airport, 6.1 mi S | May 6 | Oct 10 |
| 48505 | 6a | Flint Bishop International Airport, 7.6 mi SSW | May 6 | Oct 10 |
| 48506 | 6a | Flint Bishop International Airport, 9.4 mi SW | May 6 | Oct 10 |
| 48507 | 6a | Flint Bishop International Airport, 1.6 mi W | May 6 | Oct 10 |
Planting dates for popular crops in Flint
| Plant | Start indoors | Plant or sow outdoors | Fall planting |
|---|---|---|---|
| Tomatoes | Mar 29 to Apr 12 | May 24 to Jun 7 | — |
| Strawberries | — | Mar 25 to Apr 8 | — |
| Lettuce | Mar 11 to 25 | Apr 29 to May 13 | Jul 11 to Aug 15 |
| Cilantro | Mar 25 to Apr 8 | May 6 to 13 | — |
| Basil | Apr 5 to 19 | May 24 to 31 | — |
| Potatoes | — | Apr 26 to May 3 | — |
| Garlic | — | Mar 25 to Apr 8 | Oct 10 to 24 |
| Onions | Jan 14 to Feb 25 | Apr 8 to 22 | — |
| Cucumbers | Apr 26 to May 10 | May 24 to Jun 7 | — |
| Pumpkins | Apr 26 to May 10 | May 24 to Jun 7 | — |
| Peppers | Mar 8 to Apr 5 | May 24 to Jun 7 | — |
| Carrots | — | Apr 15 to May 6 | Jul 18 to Aug 8 |
| Sweet Potatoes | — | Jun 8 to 15 | — |
| Watermelons | Apr 19 to May 3 | May 24 to Jun 7 | — |
| Sweet Corn | — | May 6 to 20 | — |
| Green Beans | — | May 24 to Jun 7 | — |
| Zucchini | Apr 26 to May 10 | May 24 to Jun 7 | — |
| Broccoli | Feb 18 to Mar 11 | Apr 8 to 22 | Jul 25 to Aug 22 |
| Peas | — | Mar 25 to Apr 8 | Jul 18 to Aug 1 |
| Spinach | Mar 25 to Apr 1 | Apr 29 to May 13 | Aug 1 to Sep 5 |
| Sunflowers | — | May 6 to 27 | — |
| Zinnias | Jun 1 to 8 | Jun 29 to Jul 13 | — |
| Tulips | — | — | Aug 29 to Oct 24 |
| Daffodils | — | — | Aug 29 to Oct 10 |
| Grass Seed | — | Mar 25 to Apr 8 | Aug 29 to Sep 12 |
Nearby cities
- Pontiac, MI zone 6a, last frost Apr 29
- Rochester Hills, MI zone 6a, last frost Apr 26
- Novi, MI zone 6a, last frost Apr 29
- Farmington Hills, MI zone 6a, last frost May 1
- Troy, MI zone 6b, last frost Apr 26
- Southfield, MI zone 6b, last frost May 1
Planting in MichiganAbout zone 6aPrintable calendar for Flint
Questions
When is the last frost in Flint?
Around May 6 in a typical year, based on NOAA's 1991-2020 records for Flint Bishop International Airport. There is still a 1 in 10 chance of frost after May 23.
What planting zone is Flint in?
USDA hardiness zone 6a (2023 map). The zone tells you which perennials survive the winter; planting dates depend on frost dates instead.
When should I plant tomatoes in Flint?
Start seeds indoors March 29 to April 12 and set plants out May 24 to June 7.
When is the first frost in Flint?
Around October 10 in a typical year, and before September 26 about 1 year in 10.