Gardening Tips -How to Grow Tropical Fruits


CARAMBOLA (Averrhoa carambola)
Known as the Five Corner Fruit or Star Fruit the Carambola is a tree 5 10m tall which produces an odd star shaped fruit mainly over winter. Trees are best planted in the cooler months. They adapt to most soils but will not tolerate drought or exposure to salinity. They withstand some wind and dry periods but are extremely frost sensitive. Seedling plants take more than
5 years to produce fruit, but grafted trees fruit after 2 3years.

COCONUT (Cocos nucifera)
Coconut palms grow best under high humidity and average temperatures around 26 degrees celsius with daily fluctuations of no more than 5 degrees celsius. They prefer a sunny position, high annual rainfall (at least 60 inches) and a deep soil. Roots do not grow deep enough in shallow soils to anchor the plants in strong winds. They adapt to most soil types.

CUSTARD APPLE (Annona cherimola or A.reticulata)
A tree 5 8m tall tree with large bumpy round to heart shaped fruits. Deep fertile, well drained soils are prefered. They are susceptiblew to wind damage when young. Pests and diseases are rarely a serious problem.
Temperature is the most important factor, with low temperatures retarding fruit maturity and high temperatures causing premature ripening. They ideally require maximum temperatures ranging from 18 to 22 degrees celsius during fruit development and ranging from 10 to 28 degrees celsius at other times of the year. Pollination, hence fruiting can be much lower in hotter or less humid climates.

AVACADO (Persea americana)
A tree 5 12m. tall. flowering normally winter or spring and fruiting 5 14 months later, during the wet season.
Avacados are suited to tropical and sub tropical areas, but some varieties can be adapted to cooler climates. Mexican varieties will withstand lower temperatures. ("Bacon" withstands night temperatures to minus 5 degrees centigrade. "Hass" withstands to minus 1 centrigrade). In frost areas it is necessary to provide protection overhead watering has proven most successful in reducing frost damage. Good drainage is required in high rainfall areas; irrigation required in low rainfall areas. Soil fertility is not critical, but a well drained soil structure is important. North and east slopes are the preferred aspect. Avoid exposed windy sites.

Avocados are normally grown by grafting selected varieties onto seed grown plants. Some varieties produce better crops if cross pollinated (ie: If you have two or more different varieties planted together).
Normally plant on mounds or ridges for drainage and to reduce root rot, windbreak plantings are commonly required and covercrops are often grown between trees. Commonly, trees are planted initially on a 10m x 5m grid. Eventually, every second tree is removed leaving a 10m x 10m grid. Smaller growing varieties may be spaced on a 7m x 4m grid.
Handle gently when planting; tease roots if potbound, otherwise do not disturb at all. Apply fertilizer and mulch aroung the base of a newly planted tree. Keep the soil moist, but not saturated for the first few months. It may be necessary to water twice weekly. In some areas individual protection (eg: hessian around the tree) may be valuable to reduce affect of wind and sun.
Trees should be fertilized regularly, but not too heavily as over feeding makes trees more susceptible to root diseases. Nitrogen is critical too much and flowering is reduced too little and leaf is reduced. It is often a problem to establish and maintain correct nitrogen levels. Nutrient deficiencies sometimes occur with zinc, boron and iron.
Avocado trees should be pruned to develop and maintain an uneven canopy and keep trees from growing into each other. Proper pruning leads to increased productivity, better quality fruit and easier access to the tree when spraying and harvesting.
A range of pest and disease problems can occur, the worst being root rot fungus.
Fruit is hand picked upon maturity over several pickings. Larger fruits are removed first giving smaller fruits time to increase size before picking.

BANANA (Musa acuminata)
Bananas are giant narrow leaved herbaceous perennials up to 6 metres high. Individual leaves are about 2.5 metres long and 0.6 metres wide. About 9 months after planting a sucker the banana plant produces a large group of flowers which develop into a bunch of fruit.
They prefer average temperatures between 27 and 29 degrees centigrade, not below 15 and not above 35. Frost kills banana leaves; temperatures below 12 degrees centigrade will reduce fruiting. Bananas adapt to most soil types provided moisture is constant (mulching, irrigation and good drainage helps this).
Usually planted on slopes to provide good drainage; soils must retain water but never become waterlogged, mulching can be as deep as 30 cm. Feed with high nitrogen/potassium ratio fertilizers (1:3 or 1:5). Some varieties need proping (usually two pieves of timber crossed under a stem). Propagate by cutting suckers off established plants. After fruiting, cut shoots back to a stump. New shoots which emerge will provide the next season's crop. At the time when the young fruit begins to swell, the bunches are covered with plastic bags (normally blue) which the bananas will develop inside of. If bunches are covered too soon, they become mouldy; if they are not covered, fruit becomes blemished.
"Lady Fingers" is the best variety for home gardens in warm areas because it is less susceptible to disease. Cavendish varieties are better in cooler climates.
Most problems with bananas are either fungal or virus. Leaf diseases which can cause spots, burns and discoloration. Because of these diseases, in Queensland it is illegal to grow bananas in a home garden without a government permit.

Bananas are harvested while still green as they generally ripen better off the plant.

PAW PAW (Cariaca papaya)
Paw paws are fast growing, short lived herbaceous perennials growing up to 5 metres tall. They reach full size within 12 months of planting. Mountain Paw Paw is a related species which will grow in cooler climates (can fruit in Victoria but needs several plants for cross pollination).
For heavy production, and good quality fruit, paw paws need a warm (21 25 centigrade) frost free environment, full sun, ample soil moisture, good drainage and reasonable soil nutrition.
Plant at 2 3 metre spacing, in groups of three and thin out weaker plants later as they develop. Propagate by seed (fresh seed germinates in 2 weeks). Paw paws need protection from wind and are often interplanted with bananas or other fruits. If soil is poor, dig in manure before planting. If plants are branched they may need to be propped to avoid breaking. Old plants can be rejuvinated by cutting back to a 60 cm stump (if healthy). The cut surface is normally covered with an upturned tip to prevent cracking and rot. Allow only 2 or 3 new shoots to develop (remove the weakest). After fruit sets, thin it out to allow only 2 to 3 fruits per node.
Fungus and virus diseases can be serious. Mites can also pose a problem at times.
Pick individual fruits while still green just beginning to show a tinge of yellow at the end.

GUAVA (Psidium guajava)
Preferring a tropical or sub tropical climate this small tree produces its aromatic unusually flavoured fruit in late summer to early winter.Trees grown in temperate climates tend not to set fruit or the fruit is of poor flavour. Propagate from seed or grafting for superior varieties.In temperate climates the Strawberry Guava (Psidium cattleianum) and the Pineapple Guava (Feijoa sellowiana) are grown.

MANGO (Mangifera indica)
An important tropical fruit, very frost tender, hot climate essential, best on well drained sandy loam to loam soils. Tend strongly towards biennial bearing (crop heavy one year and light the next). Propagate some types from seed, others are budded onto seedlings.

ROSELLA (Hibiscus sabdariffa)
The edible part of this plant is the fleshy calyx which holds the flower.
These can be made into sauces, jam, jellies and used with desserts.the flavour is acidic.Sow seed in spring in a warm sunny position in most soils.

PINEAPPLE (Ananas comosus)
Pineapples are usually planted in summer so the fruit which takes about 2 years to mature can be harvested in summer. They prefer slightly acidic soil, well drained and rich in organic matter and must have a sunny position. They are easy to start, simplky planting the spiny top cut from a pineapple fruit. Do this by cutting the top close to the fruit, removing the bottom leaves then hanging upside down for two days (to partly dry out) before planting.
Regular feeding is needed for good results. To avoid trace element problems place 5gm of Epsom salts and a few rusty nails placed at the base of each plant a few weeks after planting. Apply 30 50gm of a general fertilizer to each plant annually Always keep the plants well watered but always avoid waterlogging.
The smooth "Cayenne" varieties are best for home gardens.


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