Luke Rotich works on his mango farm at Lomanira village in Mogotio subcounty. [Mercy Kahenda, Standard]
We all love a rich garden that gives fruits every year. Most farmers think it is a one-year process.
To begin with, a farmer needs to determine what their goals for the orchard will be.
Priorities, work plans, and evaluation methods will be set in place at this time. Before the trees are planted, the soil must be tested for nutrients, and there needs to be a specific plan for what will be planted.
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Plant the tree saplings in densities that will encourage pollination and maximum growth. The following activities are critical for a thriving orchard.
Fertilising
During the first three years, fertilisers are used to promote rapid tree growth. Do not apply fertiliser until the trees produce their first leaf flush.
Amend your nutrition applications to suit local situations. In year one, use 30g of urea or equivalent every month, 30g of mixed fertiliser every three months, and a little organic matter in the soil. Increase the urea and mixed fertiliser to 40g, 60g, and 80g in subsequent years.
Continuously add organic matter. Note that too much organic or inorganic fertilisers can kill trees, especially on shallow, poorly drained soils. Keep fertilisers at least 20cm away from the trunk to avoid tissue burn.
Apply the fertiliser evenly under the canopy and out to a point 30cm past the dripline or edge of the canopy.
Irrigating
Supplementary watering during the first few years will assist tree establishment. The timing and quantity of water vary with tree size, soil, weather, and time of year.
In year one, with a canopy diameter of 0.5m, use three litres per tree. This increases to 12 litres, 30 litres, and 60 litres in years two (canopy diameter of 1.0 m), three (canopy diameter of 1.5m), and four (canopy diameter of 2.0m).
Irrigate two to three times a week in sands and one to two times a week in heavy clays. Mulching can assist water conservation, particularly in the absence of irrigation.
Micro-sprinkler irrigation is a low-pressure, low to medium-volume irrigation system suitable for fruit trees.
Appropriately managed, micro-irrigation can increase yields, decrease water use, fertiliser, and labour requirements when compared to gated pipe/furrow irrigation systems.
Pruning
Prune young trees to provide a strong structure, minimise wind damage and increase fruit-bearing area.
Cultivars with long branches are susceptible to branch splitting, while others with short, dense crowns can break off at the ground.
Trees should be inspected regularly during the first four years. Remove weak branches because they can later split away from the trunk and destroy the tree.
Don’t remove branches until the trees are at least one year old.
Pests
The most important pest of young trees is a mite. The mite causes the leaf surface to blister, while the underside develops a brown felting.
If not controlled, the pest can damage trees and reduce flowering and fruit production. The best control is to prevent the mite from entering your property by dipping new trees.
If symptoms appear, remove and burn infested leaves. If most of the trees are infested, spray each new growth flush with dimethoate or wetable sulfur every 10 to 14 days, from just before the flush emerges until it hardens off.
Repeat for each new flush. Stop spraying once the new growth shows no symptoms.
Sulfur is less disruptive to beneficial insects and is preferred, except during hot weather. Occasionally, ants, scales, leaf-eating caterpillars, leaf-eating beetles, and twig girdlers attack young trees.
These can be controlled with registered chemicals. Borers sometimes attack individual branches, although whole trees rarely die. No chemicals are effective against these pests.
