When to plant watermelons in Ponta Grossa: 4 September – 15 March

In Ponta Grossa, watermelon: sow for seedlings from 17 July to 16 February; plant into a greenhouse from 14 August to 15 March; plant out into open ground from 4 September to 15 March.

Watermelon in Ponta Grossa: soil, season and weather

In Ponta Grossa the soil, not frost, sets the date: the last frost is over around 19 July, but the top 7 cm of soil reaches 18 °C — the minimum on the watermelon card — only around 4 September, 47 days later.

Last spring frost	19 July
Top 7 cm of soil at 18 °C	4 September, 47 days after the last frost
Into an unheated greenhouse	14 August – 15 March; August outside: 10.7 °C at night, 21.4 °C by day; card 18–35 °C
First autumn frost	24 June, 294 days after the start
Days in the bed to the first harvest (card)	59
First harvest, if planted in this window	2 November – 13 May
Days left for picking	235
Daylight	11:04 on 7 August, 11:40 on 4 September
Watering outdoors when fruiting (card)	every 5 days; the driest month, April, has 9 rainy days

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

Watermelon in Ponta Grossa: care after planting

Planted on 4 September: in the first weeks water every 5 days.

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

4 September — 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 Ponta Grossa during the watermelon season

No month of the season averages above the watermelon card's 18–35 °C by day; the warmest, December, averages 26.4 °C. Nights average below 18 °C in February–June and September–December (10.7–17.7 °C).

Month	Day, °C	Night, °C	Rain, mm	Rainy days	Daylight on the 15th
September	24.7	13.6	95	10	11:56
October	24.5	14.8	171	16	12:39
November	25.3	15.3	114	14	13:20
December	26.4	17.2	163	16	13:41
January	26.4	18	179	22	13:32
February	26.3	17.7	133	17	12:56
March	26.1	17.3	120	17	12:16
April	24.2	15	75	9	11:31
May	21.6	12.3	98	9	10:55
June	20	10.7	117	10	10:35

ERA5 2016–2025, Open-Meteo

Watermelon in nearby cities

Around Ponta Grossa, Cascavel is 41 days earlier and Lages 20 days later.

City	Distance	Date	Difference
Curitiba	97 km	from 3 September	1 day earlier
Guarapuava	136 km	22 September – 14 March	18 days later
Lages	304 km	24 September – 14 March	20 days later
Chapecó	332 km	12 September – 14 March	8 days later
Cascavel	333 km	25 July – 19 March	41 days earlier
Passo Fundo	417 km	8 September – 8 March	4 days later

Where to buy watermelon plants and seeds near Ponta Grossa

Buy plants ready to set out from 4 September to 15 March (from 14 August to 15 March for an unheated greenhouse); seed for raising your own is sown from 17 July to 16 February. Within 15 km of Ponta Grossa OpenStreetMap lists 1 farm-supply shop, 3 markets and 1 farm shop (collected 27 October 2026).

Casa Arnel — farm shop
1 km
Socidisco — farm supply
1 km
Feirinha — market
1 km
Mercado Cláudia — market
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.

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