FRUIT Growing papayas

This week’s article focuses on the nutrients, such as calcium, magnesium and nitrogen, that are required by the papaya tree.

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Dolomitic lime supplies the soil with the important nutrients calcium and magnesium. At the same time, it reduces soil acidity and the levels of potentially toxic elements such as aluminium and manganese. The quantity of lime required will depend on the pH, aluminium (extractable acidity) and the clay content of a soil.

Because lime moves slowly in the soil, you should broadcast it and incorporate it into the soil to a depth of at least 500mm before planting. After planting, apply lime once a year at a rate of 1t/ha to 2t/ ha to avoid re-acidification of the soil caused by fertilisers, rainfall and irrigation.

Apply the lime early in the season but not within three weeks of a nitrogen application.

• Phosphorus

Phosphorus (P) is an important nutrient for papayas at the vegetative stage as it promotes healthy roots, stimulates vegetative growth, and enhances flower initiation and fruit set.

However, because P remains in the soil for a long time and the papaya plant requires relatively little of it, avoid overapplication. Giving the plant too much may result in iron and zinc deficiencies and reduce yield and fruit quality.