Sweet Pineapples

Sweet Pineapples

Common name: Pineapple
Botanical name: Ananas comosus
Origin: Tropical Mesoamerica

Suitable climates
Pineapples are one of the most important subtropical crops cultivated in northern KwaZulu-Natal, the Eastern Cape and parts of the Limpopo Province. They require warm, humid weather without extreme temperature variations, 25°C being optimal. If planted in areas that don’t meet these requirements, the plants will either produce smaller fruit or none at all.

Cultivars or varieties
Two of the five major pineapple cultivars grown throughout the world are commonly planted in South Africa. The ‘Smooth Cayenne’ cultivar, the larger of the two, is used commercially for canning and is also sold as a fresh fruit. The ‘Queen’ cultivar, because of its high sugar content and unsuitability for canning, is produced for fresh consumption only.

Pineapple cultivars are propagated not by planting seeds, but by re-planting various parts of an existing pineapple plant. Both the ‘Cayenne’ and ‘Queen’ cultivars can be grown using the crown from the top of the fruit, however the ‘Queen’ cultivar takes longer to bear fruit if propagated this way. It is thus better to propagate the ‘Queen’ cultivar using the suckers that grow from the leaf axils, stem bases or below the fruit. To do so, cut off the sucker with a sharp knife, dip the cut area in fungicide and then allow it to dry for several days. Thereafter plant the sucker in a mixture of sand and compost until it has rooted, and then plant it out into the garden. The crowns can be planted straight into the ground after they
have been broken off from the fruit (not twisted) and dipped in fungicide. Plant crowns 30cm apart.

Growth habit
Pineapples are part of the bromeliad family and grow in a rosette. They have long, narrow, succulent leaves that sport sharp curved hooks on the edges. If planted thickly enough the plants may even be used as a low security barrier.

Growing requirements
The most important factor for a good crop of pineapples is excellent drainage. This is considered so crucial that it has resulted in the silting up of rivers in the pineapple-growing districts of the Eastern Cape. This is because the rows of pineapples are planted facing down the hill slopes, as opposed to the general norm of planting along the contours of the slopes (which reduces erosion by trapping run-off). Pineapples will grow in a variety of soil types but prefer slightly acidic soils with a pH of 5.5 to 6.5. Before planting, the soil should be loosened to a depth of approximately 800mm to encourage good root growth, and the soil ridged for better drainage. Pineapples planted between July and December, when the temperature is the best for the plants, will grow quickly and uniformly. They should be watered regularly, particularly when they are young, and the soil covered with a thick layer of mulch. The plants are able to utilise rainwater and dew especially well, but need watering in dry periods. Nitrogen-rich fertiliser should be applied every 3 – 4 weeks during the growing season.

Pineapples are able to self-pollinate, but are self-sterile so the fruit from this process is seedless, which is a desirable characteristic. Eating a seedy pineapple has been likened to eating a pineapple that contains a thousand tiny bits of gravel (Collins, J.L. 1960). The sticky nature of their pollen means that pineapples are unlikely to be cross-pollinated by wind, and the main cross pollinator is the hummingbird. (Hawaii has laws banning the importation of hummingbirds to protect its pineapple trade.)

Each plant produces a single fruit that should be harvested 7 – 14 days after it turns yellow. This is done by cutting the stem below the fruit. The sharp spines on the leaves can cause nasty cuts so avoid contact with hands and legs.

Interesting facts:

  •  Explorers, on seeing the pineapple for the first time, named it for its resemblance to a pinecone.
  • Sailors carried pineapples aboard their ships because the high Vitamin C content helped to prevent scurvy.
  • It is believed that Jan van Riebeeck was the first to bring pineapples to South Africa. However, it wasn’t until the mid-1800s that they were grown, first in KwaZulu-Natal and a few years later in the Eastern Cape.
  • Working with pineapples can be hazardous – those in the industry know how painful an injury from the spines can be. Due to the bromelain content, workers cutting pineapples can have their fingerprints obliterated over time.