Plymouth, Minnesota planting calendar and frost dates
Plymouth is in USDA hardiness zone 5a. The last spring frost typically comes around April 29 and the first fall frost around October 12, giving about 163 frost-free days a year.
- Hardiness zone
- Zone 5a
- Typical last frost
- April 29
- Typical first frost
- October 12
- Frost-free season
- 163 days
Frost dates in Plymouth
Last spring frost
- April 15Risky: frost later than this in 9 years out of 10
- April 29Typical: a later frost in half of years
- May 12Safe: a later frost only 1 year in 10
First fall frost
- September 29Risky: frost earlier than this 1 year in 10
- October 12Typical: 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 163 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 19 and returns around October 22.
NOAA U.S. Climate Normals 1991-2020 for New Hope, 5.8 miles ESE 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 Plymouth
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, 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: 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, 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, 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, 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 Plymouth
All 4 of Plymouth's main ZIP codes take their frost dates from New Hope, so the dates on this page apply across the city. Every one of them is in zone 5a.
| ZIP code | Zone | Weather station | Typical last frost | Typical first frost |
|---|---|---|---|---|
| 55441 | 5a | New Hope, 2.5 mi E | Apr 29 | Oct 12 |
| 55442 | 5a | New Hope, 3.6 mi SE | Apr 29 | Oct 12 |
| 55446 | 5a | New Hope, 5.8 mi ESE | Apr 29 | Oct 12 |
| 55447 | 5a | New Hope, 5.4 mi E | Apr 29 | Oct 12 |
New Hope also supplies the frost dates for St. Louis Park, so their planting calendars match Plymouth's.
Planting dates for popular crops in Plymouth
| Plant | Start indoors | Plant or sow outdoors | Fall planting |
|---|---|---|---|
| Tomatoes | Mar 26 to Apr 9 | May 21 to Jun 4 | — |
| Strawberries | — | Mar 18 to Apr 1 | — |
| Lettuce | Mar 4 to 18 | Apr 22 to May 6 | Jul 13 to Aug 17 |
| Cilantro | Mar 18 to Apr 1 | Apr 29 to May 6 | — |
| Basil | Apr 2 to 16 | May 21 to 28 | — |
| Potatoes | — | Apr 25 to May 2 | — |
| Garlic | — | Mar 18 to Apr 1 | Oct 12 to 26 |
| Onions | Jan 7 to Feb 18 | Apr 1 to 15 | — |
| Cucumbers | Apr 23 to May 7 | May 21 to Jun 4 | — |
| Pumpkins | Apr 23 to May 7 | May 21 to Jun 4 | — |
| Peppers | Mar 5 to Apr 2 | May 21 to Jun 4 | — |
| Carrots | — | Apr 8 to 29 | Jul 20 to Aug 10 |
| Sweet Potatoes | — | Jun 5 to 12 | — |
| Watermelons | Apr 16 to 30 | May 21 to Jun 4 | — |
| Sweet Corn | — | Apr 29 to May 13 | — |
| Green Beans | — | May 21 to Jun 4 | — |
| Zucchini | Apr 23 to May 7 | May 21 to Jun 4 | — |
| Broccoli | Feb 11 to Mar 4 | Apr 1 to 15 | Jul 27 to Aug 24 |
| Peas | — | Mar 18 to Apr 1 | Jul 20 to Aug 3 |
| Spinach | Mar 18 to 25 | Apr 22 to May 6 | Aug 3 to Sep 7 |
| Sunflowers | — | Apr 29 to May 20 | — |
| Zinnias | May 25 to Jun 1 | Jun 22 to Jul 6 | — |
| Tulips | — | — | Aug 31 to Oct 26 |
| Daffodils | — | — | Aug 31 to Oct 12 |
| Grass Seed | — | Mar 18 to Apr 1 | Aug 31 to Sep 14 |
Nearby cities
- Minnetonka, MN zone 5a, last frost Apr 23
- Maple Grove, MN zone 5a, last frost Apr 30
- St. Louis Park, MN zone 5a, last frost Apr 29
- Brooklyn Park, MN zone 5a, last frost Apr 30
- Minneapolis, MN zone 5a, last frost Apr 23
- Edina, MN zone 5a, last frost Apr 23
Planting in MinnesotaAbout zone 5aPrintable calendar for Plymouth
Questions
When is the last frost in Plymouth?
Around April 29 in a typical year, based on NOAA's 1991-2020 records for New Hope. There is still a 1 in 10 chance of frost after May 12.
What planting zone is Plymouth in?
USDA hardiness zone 5a (2023 map). The zone tells you which perennials survive the winter; planting dates depend on frost dates instead.
When should I plant tomatoes in Plymouth?
Start seeds indoors March 26 to April 9 and set plants out May 21 to June 4.
When is the first frost in Plymouth?
Around October 12 in a typical year, and before September 29 about 1 year in 10.