Last and first frost dates in Ann Arbor

When is the last frost in Ann Arbor?

The last frost in Ann Arbor usually comes around 28 April: that is the median of 2016–2025, so in about half of those years the last night at or below 0 °C came later. Hardy crops start before it and frost-tender ones only after it: in the table below arugula can go into open ground from 7 April, while corn waits until 5 May. The first autumn frost follows around 5 November, about 191 days later: harvest or cover frost-tender crops before then.

When to sow and plant

Planting out: a week after the last frost once the soil is warm enough for the crop; frost-hardy crops three weeks before it; an unheated greenhouse three weeks earlier. Seedlings are sown so they are ready on that day. Each window starts on the Greenly calendar date and ends on the last day that still leaves the crop’s days to harvest (from its card) before the average first autumn frost, plus six weeks of picking for crops harvested over weeks (tomatoes, peppers, aubergines, cucumbers, courgettes, pumpkins, watermelons, beans) — our rule; earlier in the window is safer.

When the soil warms up in Ann Arbor

The day the top 7 cm of soil first averages each temperature over a week, median of 2016–2025 (ERA5 via Open-Meteo). The soil reaches 10 °C 6 days before the last spring frost and 15 °C 19 days after it.

Frost dates near Ann Arbor

Of the nearest cities on our list, the last spring frost ends earliest in Toledo (United States) (22 April) and latest in Grand Rapids (28 April).

Seeds, seedlings and markets in Ann Arbor

Within 15 km of Ann Arbor OpenStreetMap lists 4 garden centres, 1 farm-supply shop, 2 plant nurseries, 10 markets and 5 farm shops (collected 28 October 2026). The nearest garden centre to the city centre is Downtown Home and Garden, 0 km away.

• Downtown Home and Garden — garden centre
  South Ashley Street 210 · Mon–Sat 07:30–19:00; Sun 10:00–17:00 · 0 km · downtownhomeandgarden.com
• Diuble Equipment Inc. — farm supply
  South Parker Road 4365 · 14 km · diubleequipment.com
• Mir's Oriental Rugs — market
  South Main Street 331 · 0 km · mirsrugs.com
• The Farm at Trinity Health - Ann Arbor — farm shop
  McAuley Drive 5557, 48197 Ypsilanti · 9 km · trinityhealthmichigan.org
• Turner's Nursery & Landscaping — garden centre
  South Wagner Road 4431, 48103 Ann Arbor · 7 km
• Ann Arbor Farmers Market — market
  Detroit Street 315, 48104 Ann Arbor · Jan–Apr Sat 08:00–15:00; May–Dec Sat, Wed 07:00–15:00 · 1 km · a2farmersmarket.org

• Where to buy seeds and seedlings in Ann Arbor
• Selling your own harvest in the United States

Places: © OpenStreetMap contributors, ODbL.

Weather in Ann Arbor by month

Average weather in Ann Arbor over 2016–2025: the warmest month is July. Months that average 20 °C or more by day: May–September (20.6–28.1 °C). Nights average below 0 °C in December–March (-6.8–-1.3 °C). About 929 mm of rain falls in a year, on 135 days; July is the wettest month (92 mm) and November the driest (56 mm).

Average of the daily highs and lows, rain per month and days with at least 1 mm (ERA5 via Open-Meteo, the same grid cell as the frost dates).

Planted in autumn

From a month before the first autumn frost, so the roots grow before winter, to the late-planting limit on each crop’s page (about two weeks before the ground freezes, by ten years of weather).