When to plant tomatoes in Ann Arbor: 17 May – 16 July

In Ann Arbor, tomato: sow for seedlings from 5 March to 25 May; plant into a greenhouse from 26 April to 16 July; plant out into open ground from 17 May to 16 July. For plants and seeds, the places nearby include Downtown Home and Garden (garden centre, 0 km) and Turner's Nursery & Landscaping (garden centre, 7 km); addresses and opening hours are below.

Tomato in Ann Arbor: soil, season and weather

In Ann Arbor the soil, not frost, sets the date: the last frost is over around 28 April, but the top 7 cm of soil reaches 15 °C — the minimum on the tomato card — only around 17 May, 19 days later.

Last spring frost	28 April
Top 7 cm of soil at 15 °C	17 May, 19 days after the last frost
Into an unheated greenhouse	26 April – 16 July; April outside: 3 °C at night, 14 °C by day; card 16–27 °C
First autumn frost	5 November, 172 days after the start
Days in the bed to the first harvest (card)	70
First harvest, if planted in this window	26 July – 24 September
Days left for picking	102
Daylight	12:24 on 26 March, 14:38 on 17 May
Watering outdoors when fruiting (card)	every 3 days; the driest month, November, has 10 rainy days

Tomato in Ann Arbor: care after planting

Planted on 17 May: in the first weeks water every 4 days.

Feeding, by the card’s schedule from that day:

17 May — feed: balanced (NPK)
14 June — feed: nitrogen

Pests and diseases of tomato to watch for:

Dates count from the first planting day of the window above; a later planting moves them by as many days.

Weather in Ann Arbor during the tomato season

Days average above the tomato card's 16–27 °C in July (28.1 °C). Months that stay below 16 °C even by day on average: November (8.7 °C). Nights average below 16 °C in May, June and September–November (0.9–15.5 °C).

Month	Day, °C	Night, °C	Rain, mm	Rainy days	Daylight on the 15th
May	20.6	9.7	88	13	14:34
June	26.3	15.5	87	12	15:15
July	28.1	18	92	13	14:59
August	26.9	17.1	87	11	13:56
September	23.7	14.1	73	9	12:32
October	16.7	8	86	12	11:07
November	8.7	0.9	56	10	9:49

ERA5 2016–2025, Open-Meteo

Tomato in nearby cities

All the nearest cities on our list plant tomato earlier than Ann Arbor; the closest date is in Lansing, 1 day earlier.

City	Distance	Date	Difference
Detroit	58 km	14 May – 18 July	3 days earlier
Windsor	60 km	14 May – 18 July	3 days earlier
Toledo (United States)	72 km	9 May – 18 July	8 days earlier
Lansing	82 km	16 May – 13 July	1 day earlier
Grand Rapids	174 km	15 May – 14 July	2 days earlier
Fort Wayne	176 km	9 May – 13 July	8 days earlier

Where to buy tomato plants and seeds near Ann Arbor

Buy plants ready to set out from 17 May to 16 July (from 26 April to 16 July for an unheated greenhouse); seed for raising your own is sown from 5 March to 25 May. 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).

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
Turner's Nursery & Landscaping — garden centre
South Wagner Road 4431, 48103 Ann Arbor · 7 km
Diuble Equipment Inc. — farm supply
South Parker Road 4365 · 14 km · diubleequipment.com
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

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.

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