USDA Hardiness Zone 6a
Frost Dates for 48734 — Frankenmuth, Michigan
NOAA 1991–2020 normals from Frankenmuth 1SE, MI (635 ft), 2 miles southeast.
Updated
In Frankenmuth, the last spring frost (32°F) is around May 3 in half of years and has passed by May 20 in nine years out of ten. The first fall frost comes around October 12, as early as September 28 one year in ten, leaving a typical freeze-free season of 161 days (NOAA, Frankenmuth 1SE, MI).
- Last spring frost
- May 3
- First fall frost
- October 12
- Growing season
- 161 days
- Hardiness zone
- 6a
50% probability
50% probability
freeze-free, 50%
-10 to -5°F (-23.3 to -20.6°C) coldest night
- First snow
- November 30
- Last snow
- March 30
- Winters with snow
- 100%
- Snow per year
- 40.7"
median, 1991–2020
median, 1991–2020
26 of 26 observed
NOAA normal
Frost risk by date in Frankenmuth
Half of springs at Frankenmuth 1SE, MI see their last 32°F night by May 3; only one in ten is past it by April 19, and one in ten still has one after May 20. Planting tender crops after May 10 leaves a 30% risk of a frost on them, after May 14 20%, and after May 20 10%. The 17 days between the even-odds date and the one-in-ten date is wider than at 62% of the 172 Michigan stations behind this site's ZIP pages.
In fall the first 32°F night comes by October 12 in half of years, as early as September 28 one year in ten, and holds off past October 27 one year in ten. A hard freeze of 28°F follows 13 days later, around October 25; in spring the one-in-ten date for 28°F is May 8, 12 days before the 32°F one. The freeze-free season lasts 161 days in a typical year, longer than at 56% of the 172 Michigan stations; it reaches 182 days one year in ten and falls short of 140 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 13 days longer, to about May 16, and return around October 1. Severe cold of 16°F or below comes every winter, usually between December 2 and March 21.
| Low | 90% | 80% | 70% | 60% | 50% | 40% | 30% | 20% | 10% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Apr 30 | May 4 | May 9 | May 13 | May 16 | May 19 | May 22 | May 26 | May 31 |
| 32°F | Apr 19 | Apr 24 | Apr 27 | Apr 30 | May 3 | May 6 | May 10 | May 14 | May 20 |
| 28°F | Apr 7 | Apr 13 | Apr 16 | Apr 19 | Apr 22 | Apr 25 | Apr 29 | May 2 | May 8 |
| 24°F | Mar 27 | Apr 1 | Apr 3 | Apr 6 | Apr 9 | Apr 13 | Apr 16 | Apr 19 | Apr 23 |
| 20°F | Mar 15 | Mar 20 | Mar 24 | Mar 28 | Mar 31 | Apr 1 | Apr 4 | Apr 7 | Apr 12 |
| 16°F | Mar 7 | Mar 12 | Mar 15 | Mar 18 | Mar 21 | Mar 23 | Mar 27 | Mar 30 | Apr 2 |
| Low | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Sep 17 | Sep 23 | Sep 25 | Sep 28 | Oct 1 | Oct 3 | Oct 6 | Oct 9 | Oct 13 |
| 32°F | Sep 28 | Oct 3 | Oct 6 | Oct 9 | Oct 12 | Oct 14 | Oct 18 | Oct 21 | Oct 27 |
| 28°F | Oct 9 | Oct 14 | Oct 18 | Oct 22 | Oct 25 | Oct 28 | Nov 1 | Nov 4 | Nov 8 |
| 24°F | Oct 21 | Oct 28 | Nov 1 | Nov 3 | Nov 6 | Nov 10 | Nov 13 | Nov 17 | Nov 23 |
| 20°F | Nov 2 | Nov 8 | Nov 12 | Nov 16 | Nov 20 | Nov 23 | Nov 28 | Dec 1 | Dec 6 |
| 16°F | Nov 13 | Nov 20 | Nov 25 | Nov 28 | Dec 2 | Dec 5 | Dec 9 | Dec 14 | Dec 20 |
Freeze probabilities 1991–2020 at Frankenmuth 1SE, MI, 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 48734 →Compare Frankenmuth with another place →
Compared with the next station
The nearest other station, Vassar, MI, 8 miles east of Frankenmuth, has a last frost 6 days later (May 9), a first frost 5 days earlier (October 7), a season 11 days shorter.
When it snows in Frankenmuth, Michigan
The first measurable snow (0.1 inch or more) in Frankenmuth usually arrives around November 30, and the last of the season around March 30. Those are the middle dates across the winters of 1991–2020 at Saginaw #3, MI, 11.9 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 34 days after the last snow.
Planting calendar for 48734
| When | What to do |
|---|---|
| February 22 – March 8 | Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out. |
| March 8 – March 22 | Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early. |
| April 5 – April 19 | Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil. |
| May 3 onward | Transplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast. |
| by July 20 | Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops. |
| by September 28 | Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation. |
| October 12 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 48734 is 2 miles from Frankenmuth 1SE, MI, which stands at 635 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 48415 (Birch Run). The 2023 USDA Plant Hardiness Zone Map lists ZIP 48734 in zone 6a, the band where the coldest night of the year averaged -10 to -5°F (-23.3 to -20.6°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.