The mango industry in Kenya has expanded considerably over recent years, not only in size but also in the geographical location of commercial and homestead plantings.
Main characteristics that differentiate varieties are the fruit shape, size, aroma, sweetness, color, fiber content, taste, seed size and resistance to diseases.
Proper selection of a mango cultivar for production must consider the following criteria:
• good adaptation to the local conditions (e.g. rainfall and dry periods)
• alternation of flowering and fruiting
• tolerance to pest and disease infections
• designated use and market requirements
Suitable Growing Areas
Mangoes do well in the Lowland to Upper Midland zones.
The most suitable areas for the cultivation of mangoes in Kenya are the Coastal areas, Lake Victoria region, Murang’a, Thika, Kajiado, Meru, Isiolo, Taveta, Lower Embu, Machakos, Kitui, Mbeere, Meru, Makueni, and Kerio Valley.
If irrigation is available during plant establishment, mangoes can be grown in drier areas.
Annual rainfall of 850 to 1,000 mm is sufficient for successful cultivation. A distinct dry or cold season stimulates flowering. Rain during flowering seriously reduces fruit set. After a mango tree is well established, it is drought tolerant, especially when the taproots have reached the water table.
Mango Tree Planting
Prepare the site by digging a hole that is twice as wide and deep as the root ball. Check the drainage by filling the hole with water and watching how fast it drains. Mango trees can survive some periods of flooding, but the healthiest plants are produced where soils percolate well.
Plant the young tree with the graft scar just at the soil surface. You don’t need to prune the young plant but watch for suckers from the graft and prune them off. Young mango tree care must include frequent watering as the plant establishes.
Caring For A Mango Tree
Young mango trees do benefit from regular watering and a little fertilizing until they are established. Overwatering can kill it, especially if your soil is a bit heavy. And too much nitrogen fertilizer will make it weak and sappy, all leaves and little fruit, susceptible to bugs and diseases.
The older the tree gets, the less nitrogen it needs. Phosphorus and potassium are more important.
Mulch your mango tree heavily and spread a bit of compost every now and then. If your soil is reasonable that should be all the tree needs.
Wood ash compost supplies potassium which will encourage fruiting and make the fruit taste better. For mulch, use only rough stuff like hay or lucerne, nothing that may mat down and become all soggy like grass clippings.
Pruning The Mango Tree
Usually mango pruning is done after harvest, though in some cooler areas the preferred time is just before flowering.
Ideally you prune only a little bit every year. If you let a mango tree grow much too big first, and then cut it back to a third of its size, the tree will likely skip the next crop.
Cut it back to a stump and it will take two years or more to fruit again. But amazingly they will grow back even from that!
Mango may suffer from some common insect pests, including mealy bugs, aphids and mites.
Signs of infestation include tiny webs on plants, clumps of white powdery residue, or visible insects on the plant. Treat infestations as soon as possible to prevent them from spreading to the rest of your collection. As always, start with the least toxic treatment option first, only progressing to more serious chemicals if your initial efforts fail.
Mango plants are susceptible to anthracnose, a fungal disease causing black lesions that gradually spread. Serious infected trees stop producing fruit. The best preventive measure is to plant a resistant variety in full sun where moisture will quickly evaporate. Extreme humidity fosters anthracnose and other fungal diseases. Copper-based fungicides can sometimes effective against anthracnose on mango plants, but they should not be used within 14 days of a planned fruit harvest.
Maturity and Harvesting
It takes between 90 – 160 days after flowering for the mangoes to reach maturity depending on variety.
Good harvesting practices are necessary, mangos should not be removed from the tree by beating with a stick and dropping to the ground. They should be picked by hand and if possible best to harvest with some stem (2 – 3 cm) attached to fruit. This reduces the latex which can cover the fruit if incorrectly harvested. Fruits are generally picked when they begin to change outer colour e.g. from deep green to light green in some cultivars. Pick fruit by hand or clip them off with a long stock (part connecting the fruit to the branch) about 2 – 3 cm and pack fruit in a single layer with stalks facing downwards in a box or crate for transportation to the market.
Good post-harvest handling should involve storage in boxes/ crates rather than sacks to avoid bruising.