St. Peters, Missouri planting calendar and frost dates
St. Peters is in USDA hardiness zone 6b. The last spring frost typically comes around April 8 and the first fall frost around October 29, giving about 203 frost-free days a year.
- Typical last frost
- April 8
- Typical first frost
- October 29
- Frost-free season
- 203 days
Frost dates in St. Peters
Last spring frost
- March 23Risky: frost later than this in 9 years out of 10
- April 8Typical: a later frost in half of years
- April 24Safe: a later frost only 1 year in 10
First fall frost
- October 16Risky: frost earlier than this 1 year in 10
- October 29Typical: an earlier frost in half of years
- November 12Late: frost before this in 9 years out of 10
The growing season between the typical last and first frosts is about 203 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 March 30 and returns around November 10.
NOAA U.S. Climate Normals 1991-2020 for St Charles Elm Pt, 5.4 miles E 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 St. Peters
January
Start indoors: broccoli, cabbages, cauliflower, collard greens, kale, leeks, onions, oregano, parsley, petunias, ranunculus, rosemary, snapdragons
February
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
Plant or sow outdoors: black-eyed susans, blueberries, garlic, grapes, grass seed, hollyhocks, onions, peas, poppies, raspberries, rhubarb, strawberries, turnips, wildflowers
March
Start indoors: basil, cantaloupes, celery, cilantro, eggplants, marigolds, nasturtiums, peppers, ranunculus, spinach, swiss chard, tomatoes, watermelons
Plant or sow outdoors: beets, black-eyed susans, blackberries, blueberries, broccoli, cabbages, carrots, cauliflower, chives, cilantro, collard greens, dahlias, dill, figs, garlic, gladioli, grapes, grass seed, hollyhocks, kale, leeks, lettuce, onions, parsley, peas, poppies, radishes, ranunculus, raspberries, rhubarb, roses, snapdragons, spinach, strawberries, swiss chard, turnips, wildflowers
April
Start indoors: cantaloupes, cosmos, cucumbers, okra, pumpkins, watermelons, winter squash, zucchini
Plant or sow outdoors: asparagus, basil, beets, cantaloupes, carrots, cauliflower, 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
May
Start indoors: zinnias
Plant or sow outdoors: asparagus, basil, 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
June
Plant or sow outdoors: bermudagrass, centipedegrass, green onions, okra, st. augustinegrass, zinnias, zoysiagrass
July
Plant for fall: brussels sprouts, collard greens, lettuce, swiss chard
August
Plant for fall: bearded irises, beets, broccoli, cabbages, carrots, cauliflower, collard greens, daylilies, kale, lettuce, peas, radishes, snapdragons, spinach, swiss chard, turnips
September
Plant for fall: azaleas, bearded irises, beets, broccoli, cabbages, cauliflower, clematis, coneflowers, crocuses, daffodils, daylilies, grass seed, hostas, hydrangeas, kale, kentucky bluegrass, lettuce, lilies, ornamental alliums, peonies, perennial ryegrass, radishes, roses, saffron, snapdragons, spinach, tall fescue, tulips, turnips
October
Plant for fall: crocuses, daffodils, daylilies, garlic, grass seed, hostas, hyacinths, kale, kentucky bluegrass, lilies, ornamental alliums, peonies, perennial ryegrass, radishes, saffron, tall fescue, tulips
November
Plant for fall: crocuses, garlic, hyacinths, ornamental alliums, tulips
December
Start indoors: onions
Frost dates and zones by ZIP code in St. Peters
St. Peters's 3 main ZIP codes take their frost dates from 3 different NOAA stations: the typical last frost ranges from April 4 in 63303 to April 10 in 63304. The hardiness zone is 6b in 63304, 63376, and 7a in 63303.
Planting dates for popular crops in St. Peters
| Plant | Start indoors | Plant or sow outdoors | Fall planting |
|---|---|---|---|
| Tomatoes | Mar 4 to 18 | Apr 29 to May 13 | — |
| Strawberries | — | Feb 25 to Mar 11 | — |
| Lettuce | Feb 11 to 25 | Apr 1 to 15 | Jul 30 to Sep 3 |
| Cilantro | Feb 25 to Mar 11 | Apr 8 to 15 | — |
| Basil | Mar 11 to 25 | Apr 29 to May 6 | — |
| Potatoes | — | Apr 1 to 8 | — |
| Garlic | — | Feb 25 to Mar 11 | Oct 29 to Nov 12 |
| Onions | Dec 17 to Jan 28 | Mar 11 to 25 | — |
| Cucumbers | Apr 1 to 15 | Apr 29 to May 13 | — |
| Pumpkins | Apr 1 to 15 | Apr 29 to May 13 | — |
| Peppers | Feb 11 to Mar 11 | Apr 29 to May 13 | — |
| Carrots | — | Mar 18 to Apr 8 | Aug 6 to 27 |
| Sweet Potatoes | — | May 15 to 22 | — |
| Watermelons | Mar 25 to Apr 8 | Apr 29 to May 13 | — |
| Sweet Corn | — | Apr 8 to 22 | — |
| Green Beans | — | Apr 29 to May 13 | — |
| Zucchini | Apr 1 to 15 | Apr 29 to May 13 | — |
| Broccoli | Jan 21 to Feb 11 | Mar 11 to 25 | Aug 13 to Sep 10 |
| Peas | — | Feb 25 to Mar 11 | Aug 6 to 20 |
| Spinach | Feb 25 to Mar 4 | Apr 1 to 15 | Aug 20 to Sep 24 |
| Sunflowers | — | Apr 8 to 29 | — |
| Zinnias | May 3 to 10 | May 31 to Jun 14 | — |
| Tulips | — | — | Sep 17 to Nov 12 |
| Daffodils | — | — | Sep 17 to Oct 29 |
| Grass Seed | — | Feb 25 to Mar 11 | Sep 17 to Oct 1 |
Nearby cities
- St. Charles, MO zone 6b, last frost Apr 2
- O'Fallon, MO zone 6b, last frost Apr 10
- Florissant, MO zone 7a, last frost Apr 2
- St. Louis, MO zone 7a, last frost Apr 8
- Springfield, IL zone 6a, last frost Apr 14
- Columbia, MO zone 6b, last frost Apr 5
Planting in MissouriAbout zone 6bPrintable calendar for St. Peters
Questions
When is the last frost in St. Peters?
Around April 8 in a typical year, based on NOAA's 1991-2020 records for St Charles Elm Pt. There is still a 1 in 10 chance of frost after April 24.
What planting zone is St. Peters in?
USDA hardiness zone 6b (2023 map), with parts of the city in zone 7a. The zone tells you which perennials survive the winter; planting dates depend on frost dates instead.
When should I plant tomatoes in St. Peters?
Start seeds indoors March 4 to 18 and set plants out April 29 to May 13.
When is the first frost in St. Peters?
Around October 29 in a typical year, and before October 16 about 1 year in 10.