When to plant tomatoes in Green Bay: 19 May – 10 July

In Green Bay, tomato: sow for seedlings from 7 March to 19 May; plant into a greenhouse from 28 April to 10 July; plant out into open ground from 19 May to 10 July.

Tomato in Green Bay: soil, season and weather

In Green Bay the soil, not frost, sets the date: the last frost is over around 29 April, but the top 7 cm of soil reaches 15 °C — the minimum on the tomato card — only around 19 May, 20 days later.

Last spring frost	29 April
Top 7 cm of soil at 15 °C	19 May, 20 days after the last frost
Into an unheated greenhouse	28 April – 10 July; April outside: 1.7 °C at night, 11.9 °C by day; card 16–27 °C
First autumn frost	30 October, 164 days after the start
Days in the bed to the first harvest (card)	70
First harvest, if planted in this window	28 July – 18 September
Days left for picking	94
Daylight	12:32 on 28 March, 14:56 on 19 May
Watering outdoors when fruiting (card)	every 3 days; the driest month, September, has 9 rainy days

Tomato in Green Bay: care after planting

Planted on 19 May: in the first weeks water every 4 days.

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

19 May — feed: balanced (NPK)
16 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 Green Bay during the tomato season

Days average above the tomato card's 16–27 °C in July (28 °C). Months that stay below 16 °C even by day on average: October (15.4 °C). Nights average below 16 °C in May, June and September, October (7–15.3 °C).

Month	Day, °C	Night, °C	Rain, mm	Rainy days	Daylight on the 15th
May	19.8	8.9	91	11	14:47
June	26.1	15.3	96	12	15:32
July	28	17.8	103	11	15:14
August	26.6	17	91	11	14:05
September	23	13.8	67	9	12:34
October	15.4	7	83	11	11:03

ERA5 2016–2025, Open-Meteo

Tomato in nearby cities

Around Green Bay, Chicago is 10 days earlier and Traverse City 8 days later.

City	Distance	Date	Difference
Milwaukee	165 km	19 May – 12 July	same day
Traverse City	192 km	27 May – 20 July	8 days later
Madison	196 km	16 May – 7 July	3 days earlier
Grand Rapids	256 km	15 May – 14 July	4 days earlier
Rockford	265 km	13 May – 8 July	6 days earlier
Chicago	295 km	9 May – 17 July	10 days earlier

Where to buy tomato plants and seeds near Green Bay

Buy plants ready to set out from 19 May to 10 July (from 28 April to 10 July for an unheated greenhouse); seed for raising your own is sown from 7 March to 19 May. Within 15 km of Green Bay OpenStreetMap lists 6 garden centres, 1 plant nursery and 2 markets (collected 20 October 2026).

Oneida Farmers Market — market
Water Circle Place N7332, 54155 Oneida · Jun Thu[3]–Sept 30 Thu 12:00–18:00 · 14 km · oneida-nsn.gov
The Cannery Public Market — market
North Broadway 320, 54303 Green Bay · 0 km
Ivy Trails — garden centre
11 km
Green Bay Nursury — garden centre
4 km

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.

Questions