How to grow Mangoes     Mangoes are grown over a wide area in South Africa. However, the main production areas are in the Limpopo Province with the Letsitele valley/Tzaneen, Hoedspruit/ Phalaborwa, Letsitele/Lower Letaba and the Trichardtsdal/Ofcolaco areas accounting for 60 % of total production. In Mpumalanga the Onderberg/Malelane region is the most important mango-production area. Climatic requirements • Mango trees can tolerate a wide range of climatic conditions. • The crop is successfully cultivated under conditions which vary from very hot, very humid to cool and dry, to very hot and arid. • The trees can survive in swampy conditions for an extended period of time, but will also survive in areas with an annual rainfall of less than 300 mm and temperatures as high as 45 °C.   Soil requirements Mango trees grow and produce well on various soil types. The tree often develops a fairly strong taproot shortly after planting. This taproot can continue growing until it reaches the soil water-table, and under favourable conditions can penetrate the soil to a depth of 6 m. However, most of the roots responsible for nutrient uptake are found in the top 500 mm of soil, with the largest concentrations in the top 250 mm. Depending on the conditions under which the mango is grown, i.e. dryland or under irrigation, the response to the soil type will vary.   Cultivars ·               Tommy Atkins ·               Zill ·               Kensington ·               Irwin ·               Neldica ·               Kent ·               Heidi ·               Keitt   Water requirements The annual water requirement (with no rainfall) of mature mango trees is 11 000 m3/ha/ year. Some degree of stress during flower bud development (May to July) is, however, advantageous. Water usage of trees subjected to water stress during flower-bud development is 9 500 m3/ha/year. The seasonal water usage of trees not subject to water stress, varies from 20 to 44 m3/ha/day from June to November respectively.   Macronutrients for mangoes under irrigation During the first 4 years, nitrogen (N) can be applied as 4 equal instalments in July, October, January and April. Thereafter, with fruit-bearing trees, N application will depend on cultivar and climatic variables which influence the seasonal stage at which the fruit is ready for harvest, i.e. early, mid or late season (December/January, February or March respectively). An orchard may, however, be ready for harvest at various stages in different seasons. Depending on the season of bearing, general times and rates of fertilisation are given in the table. Application after August may induce excessive vegetative growth to the detriment of fruit set and development and is therefore undesirable.   Weed control Weeds are usually controlled between rows in an orchard by means of mechanical mowing with a rotary cutter (slasher driven by a tractor). Chemical mowing, where herbicides are used, can be applied at low concentrations as an alternative. The idea is not to kill all the weeds but to slow down growth. Chemical control is normally followed by mechanical mowing. The advantage of this method is that mechanical mowing is limited, resulting in less traffic in the orchard.   Diseases Anthracnose Powdery mildew Bacterial black spot Malformation   Pests Fruitflies Mango weevil Harvesting Achar fruit Many growers have peach mango trees or other fibrous types. The fruit is harvested while still relatively small. The seed should not be allowed to harden because this causes rejection by the factories. Fibreless types can be used for achar and this often comprises small fruit that would otherwise drop naturally, or fruit where pollination was unsuccessful and the fruit is seedless and likely to drop (mules). Local market If fruit is to be marketed locally, it can be allowed to mature for longer periods on the tree. This will give it a better colour and flavour. However, if the fruit is left on the tree for too long, it will drop in a process known as spontaneous ripening. Export Only the best-quality fruit is suitable for export, as it has to undergo transport and cold storage for 28 days in order to reach foreign markets by sea. Fruit picked too green will never ripen properly whereas overripe fruit will spoil as a result of softening and the development of various diseases. It is therefore important to start picking at the correct stage. Maturity Maturity describes the stage of internal fruit development. A fruit is considered mature when it has reached the stage at which, after harvest and ripening, its eating quality will appeal to the consumer. Mango fruit is harvested at the so-called mature-green stage. This is the stage of physiological maturity at which ripening will occur, while still allowing time for handling and marketing. Maturity can be measured by using a colour chart and must not be confused with ripeness.   Ripening Ripening is the process which transforms a mature fruit into an attractive edible one. Ripeness is quite distinct from maturity. A mango may be mature, but not ripe. It is only ripe when it is ready to eat. A mature mango will ripen properly, whereas an immature one will not. The stage of maturity at picking will affect the speed of ripening, and the final quality of the edible fruit. When the fruit is removed from the tree several days before the onset of ripening, it is initially hard and green. The fruit progressively softens, changes colour and develops an aroma at a rate determined by the storage conditions and the maturity of the fruit at harvest. If fruit in a carton is of mixed maturity, it will be difficult to recommend a suitable storage temperature.   Handling (orchard to packhouse) • Fruit should be handled with extreme care. Excessive tree height is a distinct disadvantage. Pickers should keep their fingernails short to prevent fruit damage. The use of linen-type gloves is not advisable because the stem-end latex exudation would later cause the gloves to become abrasive. • Each picker should be provided with a soft rag which should be rinsed frequently in a bucket of water to which a detergent has been added. The rag is then used to wipe off and neutralise most of the latex (the juice exuding from the stem). • Latex, under some circumstances, can cause severe scorch marks on the skin of the mango. Placing the fruit on the ground to drain off latex is not recommended, as this can lead to post-harvest diseases. • It is wise to pick mangoes selectively for export by sea, because the fruit will only be reaching the consumer after a long time lapse. Because fruit size is all-important for export mangoes, pickers should be provided with rings fashioned from wire, to assist them in determining the minimum size. • Fruit should be carefully placed in non-abrasive containers and attention should be given to the prevention of sunburn (keep lugboxes in the shade). For more information you can order an E-Book contact :niel@safruitfarms.com