When to plant watermelons in Pittsburgh: 26 May – 31 July

In Pittsburgh, watermelon: sow for seedlings from 7 April to 3 July; plant into a greenhouse from 5 May to 31 July; plant out into open ground from 26 May to 31 July. For plants and seeds, the places nearby include Homewood Farmers Market (farm shop, 9 km) and Bedner's Farm Market (farm shop, 12 km); addresses and opening hours are below.

Watermelon in Pittsburgh: soil, season and weather

In Pittsburgh the soil, not frost, sets the date: the last frost is over around 19 April, but the top 7 cm of soil reaches 18 °C — the minimum on the watermelon card — only around 26 May, 37 days later.

Last spring frost	19 April
Top 7 cm of soil at 18 °C	26 May, 37 days after the last frost
Into an unheated greenhouse	5 May – 31 July; May outside: 11 °C at night, 21.4 °C by day; card 18–35 °C
First autumn frost	9 November, 167 days after the start
Days in the bed to the first harvest (card)	59
First harvest, if planted in this window	24 July – 28 September
Days left for picking	108
Daylight	13:48 on 28 April, 14:43 on 26 May
Watering outdoors when fruiting (card)	every 5 days; the driest month, November, has 10 rainy days

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

Watermelon in Pittsburgh: care after planting

Planted on 26 May: in the first weeks water every 5 days.

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

26 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 Pittsburgh during the watermelon season

No month of the season averages above the watermelon card's 18–35 °C by day; the warmest, July, averages 28.7 °C. Months that stay below 18 °C even by day on average: November (10.6 °C). Nights average below 18 °C in May, June and August–November (2–17.7 °C).

Month	Day, °C	Night, °C	Rain, mm	Rainy days	Daylight on the 15th
May	21.4	11	152	16	14:25
June	26.1	15.9	158	16	15:03
July	28.7	18.6	122	15	14:48
August	27.5	17.7	114	14	13:48
September	24.7	14.6	103	11	12:30
October	18.2	8.8	113	11	11:11
November	10.6	2	79	10	9:58

ERA5 2016–2025, Open-Meteo

Watermelon in nearby cities

Around Pittsburgh, Charleston, West Virginia is 11 days earlier and Erie 4 days later.

City	Distance	Date	Difference
Cleveland	185 km	28 May – 12 August	2 days later
Erie	188 km	30 May – 10 August	4 days later
Hagerstown	213 km	23 May – 2 August	3 days earlier
Columbus	260 km	20 May – 24 July	6 days earlier
Harrisburg	265 km	25 May – 2 August	1 day earlier
Charleston, West Virginia	271 km	15 May – 29 July	11 days earlier

Where to buy watermelon plants and seeds near Pittsburgh

Buy plants ready to set out from 26 May to 31 July (from 5 May to 31 July for an unheated greenhouse); seed for raising your own is sown from 7 April to 3 July. Within 15 km of Pittsburgh OpenStreetMap lists 11 garden centres, 4 plant nurseries, 23 markets and 4 farm shops (collected 20 October 2026).

Bedner's Farm Market — farm shop
Bower Hill Road 1520, 15241 Pittsburgh · 10:00–17:00 · 12 km · bednersfarmmarketusc.com
Homewood Farmers Market — farm shop
Jun 11–Oct 29 Sat 10:00–14:00 · 9 km
Lowe's Garden Center — garden centre
10 km
Hahn Nursery — garden centre
12 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.

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