When to plant watermelons in Constantine: 7 May – 3 September

In Constantine, watermelon: sow for seedlings from 19 March to 6 August; plant into a greenhouse from 16 April to 3 September; plant out into open ground from 7 May to 3 September.

Watermelon in Constantine: soil, season and weather

In Constantine the soil, not frost, sets the date: the last frost is over around 20 February, but the top 7 cm of soil reaches 18 °C — the minimum on the watermelon card — only around 7 May, 76 days later.

Last spring frost	20 February
Top 7 cm of soil at 18 °C	7 May, 76 days after the last frost
Into an unheated greenhouse	16 April – 3 September; April outside: 7.5 °C at night, 20.5 °C by day; card 18–35 °C
First autumn frost	13 December, 220 days after the start
Days in the bed to the first harvest (card)	59
First harvest, if planted in this window	5 July – 1 November
Days left for picking	161
Daylight	12:53 on 9 April, 13:51 on 7 May
Watering outdoors when fruiting (card)	every 5 days; the driest month, July, has 1 rainy day

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

Watermelon in Constantine: care after planting

Planted on 7 May: in the first weeks water every 5 days.

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

7 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 Constantine during the watermelon season

Days average above the watermelon card's 18–35 °C in July (36 °C). Months that stay below 18 °C even by day on average: December (14.1 °C). Nights average below 18 °C in May, June and September–December (3.8–16.2 °C).

Month	Day, °C	Night, °C	Rain, mm	Rainy days	Daylight on the 15th
May	24.7	11	59	9	14:05
June	32	16.2	17	3	14:38
July	36	19.3	2	1	14:25
August	34.3	18.7	10	3	13:34
September	29.6	16	27	6	12:27
October	24.3	11.4	36	7	11:18
November	18	6.8	52	9	10:15
December	14.1	3.8	43	8	9:42

ERA5 2016–2025, Open-Meteo

Watermelon in nearby cities

Around Constantine, Elche is 28 days earlier and Ajaccio 22 days later.

City	Distance	Date	Difference
Palermo	628 km	28 May – 13 September	21 days later
Ajaccio	644 km	29 May – 30 August	22 days later
Gandia	664 km	from 5 May	2 days earlier
Barcelona	677 km	24 May – 2 September	17 days later
Elche	680 km	from 9 April	28 days earlier
Valencia	703 km	from 22 April	15 days earlier

Where to buy watermelon plants and seeds near Constantine

Buy plants ready to set out from 7 May to 3 September (from 16 April to 3 September for an unheated greenhouse); seed for raising your own is sown from 19 March to 6 August. Within 15 km of Constantine OpenStreetMap lists 14 markets (collected 27 October 2026).

Ancien Marché Couvert — market
9 km
Marché hebdomadaire (Jeudi) — market
10 km
سوق الخروب — market
14 km
Marché Couvert du cité 1600 logts — market
15 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.

Questions