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The cultivation of watermelon
Afrikaans | Xhosa
Watermelon flourishes on new, fertile sandy-loam soils with a high humus content. The soil must be well drained. Heavy soils should be avoided. Reasonably alkaline soil is preferable.
Three watermelon pips are planted per 5 cm deep hole. They may be thinned out later. The plant width varies between 50 and 60 cm in the row and 150 and 200 cm between rows. Recommended watermelon cultivars are Charleston Grey, Sweet Princess, Crimson Sweet and Congo.
In the South-Western and Western Cape, watermelon can be planted in September/ October and, in the Northern Cape, even earlier, depending on the temperature. Planting must not take place before the soil temperature is high enough. Before planting, a fertiliser application of 500 kg of 2:3:4 per ha is recommended, and after planting, two applications of 100 kg of LAN; the first, two weeks after planting, and the second, two to three weeks later. When the first female flowers appear, a calcium-nitrate leaf spray may be applied, if it is available.
Flood irrigation is preferable in order to limit leaf diseases to the minimum. Before planting, irrigate the soil to a depth of 1,5 to 2 m, as that is the depth to which the roots can grow. In hot and in dry areas, one thorough irrigation is necessary every 14 days. Light irrigation at short intervals is not recommended.
Pollination is very important. When the flowers appear, beehives must be placed in the land (if possible, up to three beehives per ha).
Fusarium is a common cause of poor harvests. Rotational cropping can prevent this; in other words, plant watermelons on the same land only once in five years.
Weeds may not be allowed, because they compete with watermelons. Other causes of poor yield are too little water, and cold damage, which occurs when watermelon is planted too early.
At emergence, cutworms must be controlled with bait. Cucurbit flies are a common plague that can be controlled by Lebaycid (fenthion). Lebaycid must be mixed with sugar and splashed along the edge of the land. If it is sprayed, it will kill the bees.
PP Brink
ELSENBURG / NORTH WEST ADC
