Watermelon is considered one of the most widely-grown fruits in sub-tropical and tropical regions across the world. In South Africa, it is grown in Limpopo, North West, Mpumalanga and the Eastern Cape. According to Limpopo agronomist and farmer Leshalagae Mojapelo, there are some proven ways to grow this summer fruit.

As one of Mzansi’s most popular fruits, watermelon production is common amongst smallholder farmers. A smallholder himself, Mojapelo says he started growing the plant because the lifecycle and requirements were similar to that of butternut, a crop he was already growing.
He says that, for many farmers, growing seedless watermelon cultivars works better, as these plants have a shorter growth span. He, however, prefers to grow the more traditional cultivars.
“The life cycle of watermelon is between 12 and 18 weeks, and currently there’s a trend for farmers to go for the seedless watermelon because it is said to ripen very quickly. For us, we get a good response for the normal watermelon, which takes three months to ripen.”
This production guide, by the department of agriculture, land reform and rural development, says that watermelon can be planted anytime between June and October, depending on where in the country you are. The guide says the lifecycle of the plant is usually between 80 to 100 days, depending on the cultivar.
Climate and soil requirements
For watermelon plants to flourish, it needs to be grown when the temperatures range between 18°C to 35°C. The plant is incredibly sensitive to cold, with even a mild frost causing severe damage to it. Temperatures under 10°C or over 35°C are detrimental to the plant.
Additionally, the ideal soil type to grow watermelon in is sandy loam or silt loam soil. The crop can be grown in sandy soils as well, but then careful irrigation is required for the plant to flourish. Clay soils are usually considered unsuitable, and the ideal pH for the crop is between 5,8 and 6,6.
Planting requirements
Planting watermelon should only take place once the soil reaches a 15°C temperature. According to the department the configuration for planting seeded watermelon differs from that of seedless watermelon. Watermelon seeds are planted on flat beds that are two metres wide and between 20cm and 30cm deep. When planted directly, the seeds are placed between 1,2 and 1,9 metres deep. However, when planting seedless watermelon, you are required to plant rows of seeded watermelon in between in order for the plants to be pollinated. A common planting methodology includes one row of seeded watermelon for every two or three rows of the seedless variety.
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Water requirements
At his smallholding, Mojapelo says he plans his planting season around the rainfall patterns in the area. Farming in Limpopo, he knows that November and December are rainy seasons in his clime, and January is much drier.
“I know that watermelon needs much more water during the germination period, and then after emergence, it doesn’t require as much water. So I planted in the first week of December, when it was rainy. Then, when my plants started emerging between 7 to 14 days after planting, we were receiving medium rainfall. When the plants started fruiting in January, we received little rain,” he adds.
According to the departmental guide, how you water your plants affects the quality of the watermelons you produce. Plants that receive too much water during the early fruiting period produces “small, mishappen” fruit and suffers blossom-end rot. When irrigating, you need to ensure that you do not water your plants too much as the fruit can also split.
A final word of encouragement from Mojapelo: “It’s easy to go into watermelon farming because you don’t need an irrigation system. You can plan your planting around the rainfall pattern. And your products market themselves.”
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