USDA Hardiness Zone 6b
Frost Dates for 41049 — Hillsboro, Kentucky
NOAA 1991–2020 normals from Flemingsburg 2 N, KY (940 ft), 12 miles north.
Updated
In Hillsboro, the last spring frost (32°F) is around April 12 in half of years and has passed by May 2 in nine years out of ten. The first fall frost comes around October 30, as early as October 17 one year in ten, leaving a typical freeze-free season of 200 days (NOAA, Flemingsburg 2 N, KY).
- Last spring frost
- April 12
- First fall frost
- October 30
- Growing season
- 200 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 3
- Winters with snow
- 97%
- Snow per year
- 12.3"
median, 1991–2020
median, 1991–2020
29 of 30 observed
NOAA normal
Frost risk by date in Hillsboro
Half of springs at Flemingsburg 2 N, KY see their last 32°F night by April 12; only one in ten is past it by March 27, and one in ten still has one after May 2. Planting tender crops after April 19 leaves a 30% risk of a frost on them, after April 25 20%, and after May 2 10%. The 20 days between the even-odds date and the one-in-ten date is wider than at 88% of the 113 Kentucky stations behind this site's ZIP pages.
In fall the first 32°F night comes by October 30 in half of years, as early as October 17 one year in ten, and holds off past November 11 one year in ten. A hard freeze of 28°F follows 9 days later, around November 8; in spring the one-in-ten date for 28°F is April 16, 16 days before the 32°F one. The freeze-free season lasts 200 days in a typical year, longer than at 65% of the 113 Kentucky stations; it reaches 222 days one year in ten and falls short of 174 one year in ten. On average 100 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 14 days longer, to about April 26, and return around October 20. Severe cold of 16°F or below comes every winter, usually between December 19 and February 26.
| Low | 90% | 80% | 70% | 60% | 50% | 40% | 30% | 20% | 10% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Apr 9 | Apr 15 | Apr 19 | Apr 22 | Apr 26 | Apr 30 | May 4 | May 8 | May 14 |
| 32°F | Mar 27 | Apr 1 | Apr 4 | Apr 7 | Apr 12 | Apr 15 | Apr 19 | Apr 25 | May 2 |
| 28°F | Mar 14 | Mar 20 | Mar 25 | Mar 28 | Mar 31 | Apr 2 | Apr 5 | Apr 9 | Apr 16 |
| 24°F | Feb 28 | Mar 6 | Mar 12 | Mar 16 | Mar 20 | Mar 23 | Mar 27 | Mar 30 | Apr 3 |
| 20°F | Feb 14 | Feb 22 | Feb 28 | Mar 3 | Mar 7 | Mar 12 | Mar 16 | Mar 20 | Mar 26 |
| 16°F | Feb 2 | Feb 7 | Feb 13 | Feb 20 | Feb 26 | Mar 1 | Mar 5 | Mar 11 | Mar 18 |
| Low | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Oct 6 | Oct 11 | Oct 14 | Oct 17 | Oct 20 | Oct 23 | Oct 25 | Oct 28 | Oct 31 |
| 32°F | Oct 17 | Oct 22 | Oct 25 | Oct 28 | Oct 30 | Nov 1 | Nov 2 | Nov 6 | Nov 11 |
| 28°F | Oct 28 | Nov 1 | Nov 3 | Nov 5 | Nov 8 | Nov 11 | Nov 15 | Nov 18 | Nov 25 |
| 24°F | Nov 5 | Nov 10 | Nov 14 | Nov 17 | Nov 21 | Nov 25 | Nov 29 | Dec 4 | Dec 10 |
| 20°F | Nov 14 | Nov 20 | Nov 26 | Nov 30 | Dec 3 | Dec 7 | Dec 11 | Dec 18 | Dec 25 |
| 16°F | Nov 26 | Dec 3 | Dec 8 | Dec 12 | Dec 19 | Dec 23 | Dec 28 | Jan 2 | Jan 11 |
Freeze probabilities 1991–2020 at Flemingsburg 2 N, KY, 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 41049 →Compare Hillsboro with another place →
Compared with the next station
The nearest other station, Cave Run Lake, KY, 13 miles southeast of Hillsboro, has a last frost 5 days later (April 17), a first frost 5 days earlier (October 25), a season 11 days shorter.
When it snows in Hillsboro, Kentucky
The first measurable snow (0.1 inch or more) in Hillsboro usually arrives around December 14, and the last of the season around March 3. Those are the middle dates across the winters of 1991–2020 at Cave Run Lake, KY, 13 miles away: half of years saw snow earlier, half later. Snow fell in 97% of those winters. The last 32°F night of spring typically comes 40 days after the last snow.
Planting calendar for 41049
| When | What to do |
|---|---|
| February 1 – February 15 | Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out. |
| February 15 – March 1 | Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early. |
| March 15 – March 29 | Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil. |
| April 12 onward | Transplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast. |
| by August 7 | Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops. |
| by October 16 | Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation. |
| October 30 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 41049 is 12 miles from Flemingsburg 2 N, KY, which stands at 940 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 5 other ZIP codes share the station; its figures are presented in full for 41041 (Flemingsburg). The 2023 USDA Plant Hardiness Zone Map lists ZIP 41049 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.