Greeley, Colorado planting calendar and frost dates
Greeley is in USDA hardiness zone 5b. The last spring frost typically comes around May 2 and the first fall frost around October 8, giving about 159 frost-free days a year.
- Typical last frost
- May 2
- Typical first frost
- October 8
- Frost-free season
- 159 days
Frost dates in Greeley
Last spring frost
- April 17Risky: frost later than this in 9 years out of 10
- May 2Typical: a later frost in half of years
- May 14Safe: a later frost only 1 year in 10
First fall frost
- September 26Risky: frost earlier than this 1 year in 10
- October 8Typical: an earlier frost in half of years
- October 21Late: frost before this in 9 years out of 10
The growing season between the typical last and first frosts is about 159 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 20 and returns around October 18.
NOAA U.S. Climate Normals 1991-2020 for Greeley Unc, 1.6 miles SSE 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 Greeley
January
Start indoors: onions
February
Start indoors: broccoli, cabbages, cauliflower, collard greens, kale, leeks, onions, oregano, parsley, petunias, ranunculus, rosemary, snapdragons
March
Start indoors: basil, 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, marigolds, nasturtiums, okra, 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, 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: cosmos, cucumbers, okra, pumpkins, winter squash, zinnias, zucchini
Plant or sow outdoors: asparagus, basil, beets, cantaloupes, carrots, celery, chives, cilantro, cosmos, cucumbers, dahlias, dill, eggplants, figs, garden mums, ginger, gladioli, grapes, green beans, green onions, kentucky bluegrass, lavenders, leeks, lettuce, lilies, marigolds, mints, nasturtiums, okra, oregano, parsley, peanuts, peppers, perennial ryegrass, petunias, pumpkins, ranunculus, rosemary, roses, sage, snapdragons, spinach, sunflowers, sweet corn, sweet peas, sweet potatoes, swiss chard, tall fescue, thyme, tomatoes, watermelons, winter squash, zucchini
June
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, 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 Greeley
All 4 of Greeley's main ZIP codes take their frost dates from Greeley Unc, so the dates on this page apply across the city. The hardiness zone is 5a in 80631, and 5b in 80543, 80550, 80634.
Planting dates for popular crops in Greeley
| Plant | Start indoors | Plant or sow outdoors | Fall planting |
|---|---|---|---|
| Tomatoes | Mar 23 to Apr 6 | May 18 to Jun 1 | — |
| Strawberries | — | Mar 21 to Apr 4 | — |
| Lettuce | Mar 7 to 21 | Apr 25 to May 9 | Jul 9 to Aug 13 |
| Cilantro | Mar 21 to Apr 4 | May 2 to 9 | — |
| Basil | Mar 30 to Apr 13 | May 18 to 25 | — |
| Potatoes | — | Apr 13 to 20 | — |
| Garlic | — | Mar 21 to Apr 4 | Oct 8 to 22 |
| Onions | Jan 10 to Feb 21 | Apr 4 to 18 | — |
| Cucumbers | Apr 20 to May 4 | May 18 to Jun 1 | — |
| Pumpkins | Apr 20 to May 4 | May 18 to Jun 1 | — |
| Peppers | Mar 2 to 30 | May 18 to Jun 1 | — |
| Carrots | — | Apr 11 to May 2 | Jul 16 to Aug 6 |
| Sweet Potatoes | — | May 31 to Jun 7 | — |
| Watermelons | Apr 13 to 27 | May 18 to Jun 1 | — |
| Sweet Corn | — | May 2 to 16 | — |
| Green Beans | — | May 18 to Jun 1 | — |
| Zucchini | Apr 20 to May 4 | May 18 to Jun 1 | — |
| Broccoli | Feb 14 to Mar 7 | Apr 4 to 18 | Jul 23 to Aug 20 |
| Peas | — | Mar 21 to Apr 4 | Jul 16 to 30 |
| Spinach | Mar 21 to 28 | Apr 25 to May 9 | Jul 30 to Sep 3 |
| Sunflowers | — | May 2 to 23 | — |
| Zinnias | May 20 to 27 | Jun 17 to Jul 1 | — |
| Tulips | — | — | Aug 27 to Oct 22 |
| Daffodils | — | — | Aug 27 to Oct 8 |
| Grass Seed | — | Mar 21 to Apr 4 | Aug 27 to Sep 10 |
Nearby cities
- Loveland, CO zone 5b, last frost May 21
- Fort Collins, CO zone 5b, last frost May 2
- Longmont, CO zone 5b, last frost May 6
- Broomfield, CO zone 6a, last frost May 2
- Thornton, CO zone 6a, last frost May 2
- Commerce City, CO zone 6a, last frost May 4
Planting in ColoradoAbout zone 5bPrintable calendar for Greeley
Questions
When is the last frost in Greeley?
Around May 2 in a typical year, based on NOAA's 1991-2020 records for Greeley Unc. There is still a 1 in 10 chance of frost after May 14.
What planting zone is Greeley in?
USDA hardiness zone 5b (2023 map), with parts of the city in zone 5a. The zone tells you which perennials survive the winter; planting dates depend on frost dates instead.
When should I plant tomatoes in Greeley?
Start seeds indoors March 23 to April 6 and set plants out May 18 to June 1.
When is the first frost in Greeley?
Around October 8 in a typical year, and before September 26 about 1 year in 10.