USDA Hardiness Zone 6b
Frost Dates for 62442 — Martinsville, Illinois
NOAA 1991–2020 normals from Casey, IL (620 ft), 6 miles west.
Updated
In Martinsville, the last spring frost (32°F) is around April 14 in half of years and has passed by April 30 in nine years out of ten. The first fall frost comes around October 20, as early as October 5 one year in ten, leaving a typical freeze-free season of 187 days (NOAA, Casey, IL).
- Last spring frost
- April 14
- First fall frost
- October 20
- Growing season
- 187 days
- Hardiness zone
- 6b
50% probability
50% probability
freeze-free, 50%
-5 to 0°F (-20.6 to -17.8°C) coldest night
- First snow
- December 8
- Last snow
- March 3
- Winters with snow
- 100%
- Snow per year
- 11.9"
median, 1991–2020
median, 1991–2020
22 of 22 observed
NOAA normal
Frost risk by date in Martinsville
Half of springs at Casey, IL see their last 32°F night by April 14; only one in ten is past it by April 2, and one in ten still has one after April 30. Planting tender crops after April 20 leaves a 30% risk of a frost on them, after April 23 20%, and after April 30 10%. The 16 days between the even-odds date and the one-in-ten date is narrower than at 22% of the 158 Illinois stations behind this site's ZIP pages.
In fall the first 32°F night comes by October 20 in half of years, as early as October 5 one year in ten, and holds off past October 31 one year in ten. A hard freeze of 28°F follows 11 days later, around October 31; in spring the one-in-ten date for 28°F is April 17, 13 days before the 32°F one. The freeze-free season lasts 187 days in a typical year, longer than at 54% of the 158 Illinois stations; it reaches 205 days one year in ten and falls short of 166 one year in ten. On average 112 nights a year drop to 32°F or below. Nights of 36°F, when frost can still settle on leaves in low, open spots, continue 11 days longer, to about April 25, and return around October 9. Severe cold of 16°F or below comes every winter, usually between December 1 and March 8.
| Low | 90% | 80% | 70% | 60% | 50% | 40% | 30% | 20% | 10% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Apr 11 | Apr 16 | Apr 20 | Apr 23 | Apr 25 | Apr 28 | May 2 | May 5 | May 12 |
| 32°F | Apr 2 | Apr 5 | Apr 8 | Apr 10 | Apr 14 | Apr 17 | Apr 20 | Apr 23 | Apr 30 |
| 28°F | Mar 21 | Mar 26 | Mar 30 | Apr 1 | Apr 3 | Apr 5 | Apr 7 | Apr 11 | Apr 17 |
| 24°F | Mar 9 | Mar 15 | Mar 19 | Mar 22 | Mar 26 | Mar 29 | Mar 31 | Apr 3 | Apr 7 |
| 20°F | Feb 28 | Mar 6 | Mar 10 | Mar 13 | Mar 16 | Mar 19 | Mar 23 | Mar 27 | Mar 31 |
| 16°F | Feb 19 | Feb 26 | Mar 1 | Mar 4 | Mar 8 | Mar 11 | Mar 14 | Mar 18 | Mar 24 |
| Low | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Sep 26 | Oct 1 | Oct 4 | Oct 7 | Oct 9 | Oct 12 | Oct 15 | Oct 18 | Oct 22 |
| 32°F | Oct 5 | Oct 11 | Oct 14 | Oct 17 | Oct 20 | Oct 22 | Oct 24 | Oct 27 | Oct 31 |
| 28°F | Oct 17 | Oct 22 | Oct 26 | Oct 28 | Oct 31 | Nov 1 | Nov 3 | Nov 7 | Nov 12 |
| 24°F | Oct 29 | Nov 1 | Nov 4 | Nov 6 | Nov 9 | Nov 11 | Nov 14 | Nov 19 | Nov 26 |
| 20°F | Nov 5 | Nov 9 | Nov 12 | Nov 15 | Nov 19 | Nov 23 | Nov 27 | Dec 2 | Dec 8 |
| 16°F | Nov 11 | Nov 16 | Nov 22 | Nov 27 | Dec 1 | Dec 4 | Dec 9 | Dec 15 | Dec 21 |
Freeze probabilities 1991–2020 at Casey, IL, from NOAA NCEI U.S. Climate Normals. Where a temperature is reached in fewer than 99.5% of years, the dates describe only the years that reach it. Not a forecast.
Frost risk on any date in 62442 →Compare Martinsville with another place →
Compared with the next station
The nearest other station, Charleston, IL, 19 miles northwest of Martinsville, has a last frost 1 day later (April 15), a first frost 3 days later (October 23).
When it snows in Martinsville, Illinois
The first measurable snow (0.1 inch or more) in Martinsville usually arrives around December 8, and the last of the season around March 3. Those are the middle dates across the winters of 1991–2020 at Casey, IL, 5.9 miles away: half of years saw snow earlier, half later. Every one of those winters saw snow. The last 32°F night of spring typically comes 42 days after the last snow.
Planting calendar for 62442
| When | What to do |
|---|---|
| February 3 – February 17 | Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out. |
| February 17 – March 3 | Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early. |
| March 17 – March 31 | Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil. |
| April 14 onward | Transplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast. |
| by July 28 | Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops. |
| by October 6 | Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation. |
| October 20 onward | Plant garlic, mulch beds, lift tender bulbsGarlic wants a cold spell; bare soil loses structure over winter. |
The weeks before and after the 50% dates are general rules of thumb, not NOAA figures; a seed packet gives the timing for each variety.
Where these figures come from
ZIP 62442 is 6 miles from Casey, IL, which stands at 620 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 2 other ZIP codes share the station; its figures are presented in full for 62420 (Casey). The 2023 USDA Plant Hardiness Zone Map lists ZIP 62442 in zone 6b, the band where the coldest night of the year averaged -5 to 0°F (-20.6 to -17.8°C) over 1991–2020; a zone describes winter lows, not frost dates.
Hardiness zone and temperature range: USDA Plant Hardiness Zone Map 2023 (USDA-ARS, Oregon State University), ZIP-code listing, unchanged. °C converted from °F by this site.
Thirty-year averages, not a forecast: check the forecast before planting out. How stations are matched and which pages are offered to search engines: methodology.