Pineapples

In Queensland, pineapples are grown in:

  • Wide Bay
  • Sunshine Coast
  • Yeppoon
  • Coastal North Queensland
  • Atherton Tableland regions.

Grower resources

Varieties

  • Most planted cultivar worldwide
  • Leading variety for canning because of its high yields, good fruit shape, taste and sufficient fibre for firm slices and cubes
  • Predominant fresh fruit market variety
  • Slightly sweeter than Smooth Cayenne but with a moderately lower acidity
  • Highly aromatic flavour
  • Flesh is more yellow
  • Substantially higher vitamin C level
  • Slightly sweeter than Smooth Cayenne but with a similar acidity
  • Flesh is more yellow and slightly more fibrous
  • Very high vitamin C content
  • Moderately susceptible to translucency
  • Similar size fruit to 73–50 but slightly sweeter
  • Good flavour
  • Low to moderate susceptibility to blackheart, translucency and natural flower initiation
  • Similar size or slightly larger than 73–50 but slightly sweeter
  • Flesh is slightly less yellow
  • Exceptionally good flavour
  • Some resistance to translucency
  • Exceptionally sweet
  • Small to medium size fruit
  • Aromatic flavour similar to 73–50, but not as intense
  • Moderate acidity which is good in summer but may be slightly too high for winter production in some sites in South East Queensland
  • Small size fruit
  • Flesh has a crunchy, fibrous texture with high sweetness
  • Moderate acidity
  • Very prone to natural flower initiation, blackheart and fruitlet core rot

Land and climate

The best soils for pineapple production are non-compacted, well-aerated and free-draining loams, sandy loams and clay loams with no heavy clay or rock within 1m of the surface. Good drainage is essential because poor drainage leads to a weak root system, which makes the plant more susceptible to root and heart rot diseases. A soil pH in the range of 4.5–5.6 is optimal for pineapple production.

Temperature is the most important climatic factor affecting productivity. The optimum air temperature is 32°C during the day and 20°C at night.

During periods of intense sunlight and high temperature (above about 35°C), fruit is susceptible to sunburn damage. A frost-free site is essential.

For non-irrigated crops, rainfall should be well distributed throughout the year and more than 750mm per year.

Good water availability for irrigation is recommended in drier areas and is useful in all situations for watering at planting and 8–12 weeks before harvest in dry seasons. Pineapples are reasonably sensitive to saline irrigation water and yields tend to reduce if irrigation water's electroconductivity is greater than 1.28dS/m.

Irrigation can support good plant establishment—especially where smaller slips or tissue-cultured plants are planted. It also helps to maintain constant plant growth and minimise natural flower initiation.

Avoid overhead irrigation during flowering as it could contribute to fruitlet core rot developing. Watering at this stage does not usually improve fruit size. Unless it is exceptionally dry, avoid irrigation in the final 2–3 weeks before harvest to avoid depressing total soluble solids (TSS) levels.

Planting and harvesting

Good planting practices and attention to detail will help you achieve a healthy, uniform and productive pineapple crop.

Pineapples do not ripen after being harvested (non-climacteric fruit). All of a pineapple’s sugar comes from the starches in the stem of the plant. Once that source is cut off, the pineapple cannot make more sugar on its own. Pineapples are harvested at a shell colour maturity that reflects the season and sugar/acid level.

Fresh market fruit should be harvested at first break to one-quarter colour in summer and one-quarter to one-half colour in winter to achieve the best eating quality.

Besides the initial pick around headlands, an additional 2 to 3 picks will be required to achieve optimum eating quality in most fruit from a field. Fruit harvested at the right maturity and subjected to the appropriate cool-chain management should have adequate post-harvest life if sold quickly.

Handling pineapples correctly is important to reduce the risk of bruising.

Use leaf sampling to monitor nutrient status and check readiness for flower induction.

Pests and diseases

Insect pests:

  • Nematodes
  • Symphylids
  • White grubs
  • Pineapple red mite.

Diseases:

Fertilising

We recommend keeping a good balance between elements when fertilising. The balance among cations is extremely important and excessive applications of 1 element can result in a deficiency of another.

Translucency

Translucency has an underlying genetic basis but is expressed only under certain environmental conditions. It occurs when the fruit cell membranes lose some integrity and allows water to move across into the spaces between the cells. That accumulation of juice between the cells gives the water-soaked appearance and the fruit begins to ferment very quickly. This process involves bacteria and/or yeast-mediated conversion of sugars into alcohol and other compounds, resulting in an unpleasant flavour. Translucency usually occurs before the fruit has matured adequately.

Translucency is usually more prevalent in the larger fruit harvested in the first pick, or around the edges of fields. Fruit on highly vigorous plants are usually more susceptible. High nitrogen can exacerbate translucency.

The development of a slight degree of translucency is a normal part of fruit ripening and is desirable. Up to about 50% translucency in a fruit is considered acceptable or desirable. Palatability usually declines when translucency is greater than about 50%.

Translucent fruit can be identified in the pack-house through the use of flotation grading protocols.

Translucency seems to be accentuated by high temperature within about 6 weeks of harvest and is more common in spring. Higher planting densities might help reduce translucency slightly by increasing the shading of fruit. Water management does not seem to have any significant effect.

Maintaining optimum calcium levels will slightly reduce the incidence of translucency. Calcium is important for the structure and function of cell walls. However, high applications of calcium will not stop translucency.