USDA Hardiness Zone 5a
Frost Dates for 52336 — Springville, Iowa
NOAA 1991–2020 normals from Anamosa 3 SSW, IA (906 ft), 7 miles east.
Updated
In Springville, the last spring frost (32°F) is around April 27 in half of years and has passed by May 10 in nine years out of ten. The first fall frost comes around October 13, as early as September 30 one year in ten, leaving a typical freeze-free season of 170 days (NOAA, Anamosa 3 SSW, IA).
- Last spring frost
- April 27
- First fall frost
- October 13
- Growing season
- 170 days
- Hardiness zone
- 5a
50% probability
50% probability
freeze-free, 50%
-20 to -15°F (-28.9 to -26.1°C) coldest night
- First snow
- November 14
- Last snow
- March 31
- Winters with snow
- 100%
- Snow per year
- 34.3"
median, 1991–2020
median, 1991–2020
30 of 30 observed
NOAA normal
Frost risk by date in Springville
Half of springs at Anamosa 3 SSW, IA see their last 32°F night by April 27; only one in ten is past it by April 12, and one in ten still has one after May 10. Planting tender crops after May 2 leaves a 30% risk of a frost on them, after May 6 20%, and after May 10 10%. The 13 days between the even-odds date and the one-in-ten date is narrower than at 42% of the 132 Iowa stations behind this site's ZIP pages.
In fall the first 32°F night comes by October 13 in half of years, as early as September 30 one year in ten, and holds off past October 25 one year in ten. A hard freeze of 28°F follows 11 days later, around October 24; in spring the one-in-ten date for 28°F is May 1, 9 days before the 32°F one. The freeze-free season lasts 170 days in a typical year, longer than at 69% of the 132 Iowa stations; it reaches 189 days one year in ten and falls short of 151 one year in ten. On average 149 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 10 days longer, to about May 7, and return around October 4. Severe cold of 16°F or below comes every winter, usually between November 24 and March 13.
| Low | 90% | 80% | 70% | 60% | 50% | 40% | 30% | 20% | 10% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Apr 23 | Apr 28 | May 1 | May 4 | May 7 | May 9 | May 12 | May 15 | May 19 |
| 32°F | Apr 12 | Apr 16 | Apr 19 | Apr 23 | Apr 27 | Apr 30 | May 2 | May 6 | May 10 |
| 28°F | Apr 1 | Apr 5 | Apr 8 | Apr 10 | Apr 14 | Apr 17 | Apr 20 | Apr 25 | May 1 |
| 24°F | Mar 16 | Mar 23 | Mar 29 | Apr 1 | Apr 3 | Apr 6 | Apr 8 | Apr 12 | Apr 19 |
| 20°F | Mar 6 | Mar 11 | Mar 15 | Mar 19 | Mar 22 | Mar 25 | Mar 29 | Apr 1 | Apr 6 |
| 16°F | Feb 28 | Mar 3 | Mar 7 | Mar 10 | Mar 13 | Mar 15 | Mar 19 | Mar 22 | Mar 28 |
| Low | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Sep 21 | Sep 25 | Sep 29 | Oct 1 | Oct 4 | Oct 6 | Oct 8 | Oct 11 | Oct 15 |
| 32°F | Sep 30 | Oct 5 | Oct 8 | Oct 11 | Oct 13 | Oct 16 | Oct 19 | Oct 21 | Oct 25 |
| 28°F | Oct 10 | Oct 16 | Oct 19 | Oct 21 | Oct 24 | Oct 26 | Oct 28 | Oct 31 | Nov 5 |
| 24°F | Oct 21 | Oct 27 | Oct 29 | Nov 1 | Nov 2 | Nov 6 | Nov 9 | Nov 13 | Nov 17 |
| 20°F | Nov 1 | Nov 4 | Nov 8 | Nov 12 | Nov 15 | Nov 17 | Nov 21 | Nov 25 | Nov 30 |
| 16°F | Nov 8 | Nov 13 | Nov 18 | Nov 21 | Nov 24 | Nov 27 | Nov 30 | Dec 4 | Dec 10 |
Freeze probabilities 1991–2020 at Anamosa 3 SSW, IA, 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 52336 →Compare Springville with another place →
Compared with the next station
The nearest other station, Cedar Rapids #1, IA, 8 miles west of Springville, has a last frost 1 day later (April 28), a first frost 1 day earlier (October 12), a season 4 days shorter.
When it snows in Springville, Iowa
The first measurable snow (0.1 inch or more) in Springville usually arrives around November 14, and the last of the season around March 31. Those are the middle dates across the winters of 1991–2020 at Cedar Rapids #1, IA, 7.6 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 27 days after the last snow.
Planting calendar for 52336
| When | What to do |
|---|---|
| February 16 – March 2 | Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out. |
| March 2 – March 16 | Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early. |
| March 30 – April 13 | Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil. |
| April 27 onward | Transplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast. |
| by July 21 | Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops. |
| by September 29 | Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation. |
| October 13 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 52336 is 7 miles from Anamosa 3 SSW, IA, which stands at 906 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 1 other ZIP code shares the station; its figures are presented in full for 52253 (Lisbon). The 2023 USDA Plant Hardiness Zone Map lists ZIP 52336 in zone 5a, the band where the coldest night of the year averaged -20 to -15°F (-28.9 to -26.1°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.