USDA Hardiness Zone 6b
Frost Dates for 47023 — Holton, Indiana
NOAA 1991–2020 normals from N Vernon 2 ESE, IN (743 ft), 12 miles southwest.
Updated
In Holton, the last spring frost (32°F) is around April 21 in half of years and has passed by May 10 in nine years out of ten. The first fall frost comes around October 21, as early as October 7 one year in ten, leaving a typical freeze-free season of 180 days (NOAA, N Vernon 2 ESE, IN).
- Last spring frost
- April 21
- First fall frost
- October 21
- Growing season
- 180 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 14
- Last snow
- March 8
- Winters with snow
- 93%
- Snow per year
- 17.2"
median, 1991–2020
median, 1991–2020
25 of 27 observed
NOAA normal
Frost risk by date in Holton
Half of springs at N Vernon 2 ESE, IN see their last 32°F night by April 21; only one in ten is past it by April 6, and one in ten still has one after May 10. Planting tender crops after April 30 leaves a 30% risk of a frost on them, after May 4 20%, and after May 10 10%. The 19 days between the even-odds date and the one-in-ten date is wider than at 94% of the 125 Indiana stations behind this site's ZIP pages.
In fall the first 32°F night comes by October 21 in half of years, as early as October 7 one year in ten, and holds off past November 1 one year in ten. A hard freeze of 28°F follows 10 days later, around October 31; in spring the one-in-ten date for 28°F is April 28, 12 days before the 32°F one. The freeze-free season lasts 180 days in a typical year, shorter than at 54% of the 125 Indiana stations; it reaches 201 days one year in ten and falls short of 158 one year in ten. On average 102 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 May 2, and return around October 10. Severe cold of 16°F or below comes every winter, usually between December 5 and March 4.
| Low | 90% | 80% | 70% | 60% | 50% | 40% | 30% | 20% | 10% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Apr 16 | Apr 21 | Apr 25 | Apr 29 | May 2 | May 6 | May 9 | May 13 | May 19 |
| 32°F | Apr 6 | Apr 11 | Apr 15 | Apr 18 | Apr 21 | Apr 26 | Apr 30 | May 4 | May 10 |
| 28°F | Mar 23 | Mar 30 | Apr 2 | Apr 5 | Apr 8 | Apr 12 | Apr 17 | Apr 21 | Apr 28 |
| 24°F | Mar 10 | Mar 17 | Mar 22 | Mar 25 | Mar 28 | Mar 31 | Apr 3 | Apr 7 | Apr 14 |
| 20°F | Feb 25 | Mar 3 | Mar 8 | Mar 11 | Mar 15 | Mar 19 | Mar 22 | Mar 28 | Apr 1 |
| 16°F | Feb 12 | Feb 20 | Feb 26 | Feb 28 | Mar 4 | Mar 8 | Mar 12 | Mar 16 | Mar 22 |
| Low | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Sep 29 | Oct 3 | Oct 6 | Oct 8 | Oct 10 | Oct 13 | Oct 15 | Oct 18 | Oct 22 |
| 32°F | Oct 7 | Oct 12 | Oct 16 | Oct 18 | Oct 21 | Oct 23 | Oct 25 | Oct 28 | Nov 1 |
| 28°F | Oct 17 | Oct 22 | Oct 25 | Oct 28 | Oct 31 | Nov 1 | Nov 4 | Nov 7 | Nov 12 |
| 24°F | Oct 28 | Nov 1 | Nov 4 | Nov 7 | Nov 10 | Nov 13 | Nov 17 | Nov 23 | Dec 1 |
| 20°F | Nov 6 | Nov 11 | Nov 15 | Nov 19 | Nov 23 | Nov 27 | Dec 1 | Dec 5 | Dec 12 |
| 16°F | Nov 16 | Nov 24 | Nov 28 | Dec 1 | Dec 5 | Dec 9 | Dec 15 | Dec 21 | Dec 27 |
Freeze probabilities 1991–2020 at N Vernon 2 ESE, IN, 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 47023 →Compare Holton with another place →
Weather by month in Holton
July is the warmest month at N Vernon 2 ESE, IN, averaging 86°F by day and 65°F at night; January is the coldest at 40°F and 23°F. A freezing night is all but certain in every month from November to April (a 90% chance or more). From June to September the chance of a 32°F night stays under 10% each month. In spring, May still brings one in 28% of years.
Warmth for growing adds up to 3,789 growing degree days a year (base 50°F), more than at 75% of the 125 Indiana stations. 38% of them (1,422) have built up by the end of June, and July adds the most, 783. Precipitation totals 49.4 inches a year, most in April (5.3") and least in February (3.2"); May to September bring 45% of it.
| Month | High °F | Low °F | Precip. in | 32°F night | Nights ≤ 32°F | GDD 50°F |
|---|---|---|---|---|---|---|
| Jan | 40 | 23 | 3.4 | 100% | 24 | 7 |
| Feb | 45 | 26 | 3.2 | 100% | 20 | 15 |
| Mar | 55 | 34 | 4.2 | 100% | 15 | 72 |
| Apr | 67 | 44 | 5.3 | 95% | 5 | 220 |
| May | 75 | 53 | 4.9 | 28% | <1 | 445 |
| Jun | 83 | 61 | 5.1 | 0% | 0 | 663 |
| Jul | 86 | 65 | 4.5 | 0% | 0 | 783 |
| Aug | 85 | 63 | 4.5 | 0% | 0 | 745 |
| Sep | 79 | 56 | 3.3 | 2% | 0 | 524 |
| Oct | 68 | 45 | 3.5 | 87% | 3 | 239 |
| Nov | 55 | 35 | 3.8 | 100% | 13 | 63 |
| Dec | 44 | 28 | 3.7 | 100% | 21 | 13 |
Monthly normals 1991–2020 at N Vernon 2 ESE, IN (743 ft), NOAA NCEI. "32°F night": chance of at least one in the month. GDD: growing degree days, base 50°F.
Compared with the next station
The nearest other station, Milan 5 NE, IN, 19 miles east of Holton and 232 feet higher, has a last frost 9 days later (April 30), a first frost 5 days earlier (October 16), a season 12 days shorter.
When it snows in Holton, Indiana
The first measurable snow (0.1 inch or more) in Holton usually arrives around December 14, and the last of the season around March 8. Those are the middle dates across the winters of 1991–2020 at N Vernon 2 ESE, IN, 12.4 miles away: half of years saw snow earlier, half later. Snow fell in 93% of those winters. The last 32°F night of spring typically comes 44 days after the last snow.
Planting calendar for 47023
| When | What to do |
|---|---|
| February 10 – February 24 | Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out. |
| February 24 – March 10 | Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early. |
| March 24 – April 7 | Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil. |
| April 21 onward | Transplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast. |
| by July 29 | Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops. |
| by October 7 | Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation. |
| October 21 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 47023 is 12 miles from N Vernon 2 ESE, IN, which stands at 743 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 47265 (North Vernon). The 2023 USDA Plant Hardiness Zone Map lists ZIP 47023 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.