When to plant watermelons in Caxias do Sul: 1 September – 7 March

In Caxias do Sul, watermelon: sow for seedlings from 14 July to 8 February; plant into a greenhouse from 11 August to 7 March; plant out into open ground from 1 September to 7 March.

Watermelon in Caxias do Sul: soil, season and weather

In Caxias do Sul the soil, not frost, sets the date: the last frost is over around 13 July, but the top 7 cm of soil reaches 18 °C — the minimum on the watermelon card — only around 1 September, 50 days later.

Last spring frost	13 July
Top 7 cm of soil at 18 °C	1 September, 50 days after the last frost
Into an unheated greenhouse	11 August – 7 March; August outside: 10 °C at night, 19.6 °C by day; card 18–35 °C
First autumn frost	16 June, 289 days after the start
Days in the bed to the first harvest (card)	59
First harvest, if planted in this window	30 October – 5 May
Days left for picking	230
Daylight	10:48 on 4 August, 11:30 on 1 September
Watering outdoors when fruiting (card)	every 5 days; the driest month, April, has 14 rainy days

The same dates in Caxias do Sul hold for Cucumber, Bell Pepper, Eggplant, Zucchini and Pumpkin.

Watermelon in Caxias do Sul: care after planting

Planted on 1 September: in the first weeks water every 5 days.

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

1 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 Caxias do Sul during the watermelon season

No month of the season averages above the watermelon card's 18–35 °C by day; the warmest, January, averages 27.1 °C. Months that stay below 18 °C even by day on average: June (17.6 °C). Nights average below 18 °C in February–June and September–December (9.8–17.9 °C).

Month	Day, °C	Night, °C	Rain, mm	Rainy days	Daylight on the 15th
September	21.5	12	176	14	11:54
October	22.3	13.2	187	16	12:46
November	24.3	14.4	154	14	13:34
December	26.4	16.8	149	17	14:00
January	27.1	18.3	167	20	13:48
February	26.7	17.9	136	15	13:06
March	25.2	17	150	16	12:18
April	22.8	14.6	125	14	11:24
May	19.1	11.6	199	14	10:41
June	17.6	9.8	166	12	10:17

ERA5 2016–2025, Open-Meteo

Watermelon in nearby cities

Around Caxias do Sul, Santa Maria is 18 days earlier and Lages 23 days later.

City	Distance	Date	Difference
Passo Fundo	157 km	8 September – 8 March	7 days later
Lages	172 km	24 September – 14 March	23 days later
Santa Maria	261 km	14 August – 3 March	18 days earlier
Chapecó	270 km	12 September – 14 March	11 days later
Guarapuava	421 km	22 September – 14 March	21 days later
Curitiba	457 km	from 3 September	2 days later

Where to buy watermelon plants and seeds near Caxias do Sul

Buy plants ready to set out from 1 September to 7 March (from 11 August to 7 March for an unheated greenhouse); seed for raising your own is sown from 14 July to 8 February. Within 15 km of Caxias do Sul OpenStreetMap lists 14 farm-supply shops, 3 markets and 2 farm shops (collected 27 October 2026).

Agrimar — farm supply
3 km
Agroerr — farm supply
4 km
Stella Tratores — farm supply
4 km
Agropecuária Agro Milani — farm supply
5 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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