When to plant watermelons in Milwaukee: 28 May – 23 July

In Milwaukee, watermelon: sow for seedlings from 9 April to 25 June; plant into a greenhouse from 7 May to 23 July; plant out into open ground from 28 May to 23 July. For plants and seeds, the places nearby include BK Landscape Contracting & Supplies (garden centre, 13 km) and Stein's Garden and Home (garden centre, 13 km); addresses and opening hours are below.

Watermelon in Milwaukee: soil, season and weather

In Milwaukee the soil, not frost, sets the date: the last frost is over around 27 April, but the top 7 cm of soil reaches 18 °C — the minimum on the watermelon card — only around 28 May, 31 days later.

Last spring frost	27 April
Top 7 cm of soil at 18 °C	28 May, 31 days after the last frost
Into an unheated greenhouse	7 May – 23 July; May outside: 8.8 °C at night, 18.7 °C by day; card 18–35 °C
First autumn frost	1 November, 157 days after the start
Days in the bed to the first harvest (card)	59
First harvest, if planted in this window	26 July – 20 September
Days left for picking	98
Daylight	14:03 on 30 April, 15:02 on 28 May
Watering outdoors when fruiting (card)	every 5 days; the driest month, November, has 7 rainy days

The same dates in Milwaukee hold for Cucumber, Bell Pepper, Eggplant, Zucchini and Pumpkin.

Watermelon in Milwaukee: care after planting

Planted on 28 May: in the first weeks water every 5 days.

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

28 May — feed: balanced (NPK)

Pests and diseases of watermelon 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 Milwaukee during the watermelon season

No month of the season averages above the watermelon card's 18–35 °C by day; the warmest, July, averages 27.6 °C. Months that stay below 18 °C even by day on average: October (16.2 °C) and November (8.2 °C). Nights average below 18 °C in May, June and August–November (0.9–17.8 °C).

Month	Day, °C	Night, °C	Rain, mm	Rainy days	Daylight on the 15th
May	18.7	8.8	113	13	14:38
June	25.4	15.2	116	12	15:21
July	27.6	18.3	90	10	15:04
August	26.7	17.8	81	10	13:59
September	23.4	14.9	91	10	12:33
October	16.2	8.3	98	10	11:06
November	8.2	0.9	50	7	9:45

ERA5 2016–2025, Open-Meteo

Watermelon in nearby cities

Around Milwaukee, Green Bay is 1 day earlier and Traverse City 8 days later.

City	Distance	Date	Difference
Madison	121 km	28 May – 18 July	same day
Rockford	128 km	28 May – 19 July	same day
Chicago	131 km	28 May – 28 July	same day
Green Bay	165 km	27 May – 21 July	1 day earlier
Grand Rapids	182 km	28 May – 25 July	same day
Traverse City	266 km	5 June – 31 July	8 days later

Where to buy watermelon plants and seeds near Milwaukee

Buy plants ready to set out from 28 May to 23 July (from 7 May to 23 July for an unheated greenhouse); seed for raising your own is sown from 9 April to 25 June. Within 15 km of Milwaukee OpenStreetMap lists 9 garden centres, 10 markets and 1 farm shop (collected 20 October 2026).

BK Landscape Contracting & Supplies — garden centre
West Appleton Avenue 9150, 53225-3409 Milwaukee · 13 km
Stein's Garden and Home — garden centre
Mon–Fri 09:00–19:00; Sat–Sun 09:00–17:00 · 13 km
CE Farms — garden centre
Mon–Fri 09:00–18:00; Sat 09:00–17:00; Sun 09:00–16:00 · 15 km
Milwaukee Public Market — market
North Water Street 400, 53202 Milwaukee · Mon–Wed 06:30–20:00; Thu–Fri 06:30–21:00; Sat 08:00–21:00; Sun 10:00–18:00 · 1 km · milwaukeepublicmarket.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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