When to plant watermelons in Guarapuava: 22 September – 14 March

In Guarapuava, watermelon: sow for seedlings from 4 August to 15 February; plant into a greenhouse from 1 September to 14 March; plant out into open ground from 22 September to 14 March. For plants and seeds, the places nearby include Master Campus (farm supply, 5 km); addresses and opening hours are below.

Watermelon in Guarapuava: soil, season and weather

In Guarapuava the soil, not frost, sets the date: the last frost is over around 5 August, but the top 7 cm of soil reaches 18 °C — the minimum on the watermelon card — only around 22 September, 48 days later.

Last spring frost	5 August
Top 7 cm of soil at 18 °C	22 September, 48 days after the last frost
Into an unheated greenhouse	1 September – 14 March; September outside: 12.5 °C at night, 22.6 °C by day; card 18–35 °C
First autumn frost	23 June, 275 days after the start
Days in the bed to the first harvest (card)	59
First harvest, if planted in this window	20 November – 12 May
Days left for picking	216
Daylight	11:26 on 25 August, 12:06 on 22 September
Watering outdoors when fruiting (card)	every 5 days; the driest month, April, has 9 rainy days

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

Watermelon in Guarapuava: care after planting

Planted on 22 September: in the first weeks water every 5 days.

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

22 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 Guarapuava during the watermelon season

No month of the season averages above the watermelon card's 18–35 °C by day; the warmest, December, averages 24.7 °C. Months that stay below 18 °C even by day on average: June (17.9 °C). Nights average below 18 °C in every month of the season, from 9.7 °C to 16.5 °C.

Month	Day, °C	Night, °C	Rain, mm	Rainy days	Daylight on the 15th
September	22.6	12.5	127	10	11:55
October	22.5	13.5	232	17	12:40
November	23.6	14	139	13	13:21
December	24.7	15.7	178	18	13:42
January	24.5	16.5	216	21	13:33
February	24.5	16.3	157	18	12:57
March	24	15.8	140	17	12:16
April	22.1	13.4	103	9	11:30
May	19.3	11	146	11	10:54
June	17.9	9.7	155	10	10:34

ERA5 2016–2025, Open-Meteo

Watermelon in nearby cities

Around Guarapuava, Cascavel is 59 days earlier and Lages 2 days later.

City	Distance	Date	Difference
Ponta Grossa	136 km	4 September – 15 March	18 days earlier
Cascavel	206 km	25 July – 19 March	59 days earlier
Curitiba	221 km	from 3 September	19 days earlier
Chapecó	222 km	12 September – 14 March	10 days earlier
Lages	293 km	24 September – 14 March	2 days later
Passo Fundo	332 km	8 September – 8 March	14 days earlier

Where to buy watermelon plants and seeds near Guarapuava

Buy plants ready to set out from 22 September to 14 March (from 1 September to 14 March for an unheated greenhouse); seed for raising your own is sown from 4 August to 15 February. Within 15 km of Guarapuava OpenStreetMap lists 1 farm-supply shop, 1 plant nursery and 1 market (collected 27 October 2026).

Master Campus — farm supply
BR-277 2540, 85030-230 Guarapuava - PR · Mon–Sat 08:00–18:00 · 5 km
Matilde — market
Rua Fredolin Worn · 2 km
Horta Dalpozzo — plant nursery
3 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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