Mango grows anywhere in the country. However, profitable production, ideal soil and climate should be considered.
The ideal growing conditions for mango are distinct wet and dry seasons with at least four to five months of dry period. A mango grower should consider the following soil suitability requirements and climatic conditions:
Soil characteristics:
- Sandy loam,relatively rich in organic matter
- Good drainage (very important)
- pH 6.0-7.0
- flat to slightly rolling terrain
Climatic condition
- Distinct wet and dry season (4to 5 months dry priod)
- Temperature of 21 to 30 degree celsius
- No strong winds
Elevation
- Should not be higher than 600 meters above sea level.
- 400 meters ideal for growing mango
After area selection, the mango grower is advised to plant the recommended mango varieties/strains:
GES 73, 77, 84, 85, Talaban, Fresco, Tanaleon and Guimaras Super.
These materials can be availed from nurseries accredited by the Bureau of Plant Industry (BPI).
Orchard site preparation
- land preparation
- For backyard planting, under brushung or cutting of young trees (bushes, volunteer plants) is required to clear the area. This will facilitate layout and minimize shading of newly-planted trees.
- For orchard planting, under brushing, plowing and harrowing are rquired to attain good soil tilth. These activities should be done before the onset of rainy days, in preparation for field layout.
- Planting of ‘windbreaks’ such as mahogany and acacia, along bounderies is also recommended. These trees will also serve as circumfrential fence for the orchard.
- If irrigation facilities have to be installed, these should be part of the plant for site development.
- Faucets may be strategically placed within the orchard while primary and secondary waterlines could be installad for ready access.
- An orchard shed, together with working area and storeroom may be constructed in a section of the orchard that is highly accessible to transportation facilities.
- field layout
Square System
In the square system, trees are planted in the corners of the square. This system is widely practiced because it is easy to layout. It also facilitates many cultural management practices such as pruning, bagging, etc.
In adopting the square system, one has to follow these procedures:
· Make wooden triangular frame measuring 3x4x5 meters.
· Set this frame in one corner of the field. This will serve as reference point.
· With nylon strings, extend both arms of the triangle and fix the end using bamboo poles.
· The layout can be done using another string with marked distance of planting.
· Place bamboo stick on the appropriate distance.
· Move the marked string to over the entire area.
Triangular System
The triangular system is simply done by laying out the plants in the corners of an equilateral triangle. It accommodate 15% more plants that the square system.
Quincux System
In the quincunx system, plants are laid out in the four corners and at the center of a square to maximize space. In general, it can accommodate about two times more plants than the square system.
The earlier designs (square, triangular and quincux) are appropriate for flat and slightly rolling areas.
Contour System
On the slopes of hilly land in which the threat of erosion is more likely to happen, plants are laid out on contour lines, established against the slope.
This system of planting reduces the slope length and the slope angle, thus, allowing rainwater to be withheld by the soil for sometime; allowing it to percolate and prevent runoff. The root system of the main crop further keeps the soil intact and holds the soil particles together. Laying out hilly lands is done using an A-frame starting from the upper to the lower slope.
Some guidelines in the use of contour system:
- Start laying-out from the top of the hill by establishing a baseline from the steepest slope. Each point in the reference line should be break-chained so that one can get the accurate slope distance with the changing slope downhill. Always start the determination of each contour line from the baseline.
- Drive the first stake at the desired point. Place one leg of the A-frame beside the first stake. Then, adjust the other leg on the ground such that the weighted string passes the midpoint mark on the crossbar. Drive another stake at this point.
- Move the A-frame to the next spot such that one leg touches the second stake at the side of its base.
- Repeat the above steps until the whole areas have been laid out.
- Make corrections or adjustments to the layout to take care of strange spots like gullies and rocks on the ground. This is made when contour lines go astray, or when they become too close to cause the overlapping of hills between contour lines, or too far to leave a larger area unused.
All reference lines, especially the layout made in the flatbeds, should be placed t certain distance from the border. If the borders are lined up with tree windbreaks, the distance between the windbreak and the plant should be equal to the average of their respective planting distance.
- tree spacing
The distance of planting in mango is influenced by fertility of soil, wherein fast growth is attained. Fertile soil and wider spacing are recommended for fast growing varieties. These conditions will also benefit farmers who want to plant intercrops in between rows of trees.
In general, mangoes need full sunlight for productive growth. Thus, close spacing that can result to competition of light, food and water must be avoided.
For ‘Carabao’ mango, spacing not less than 10x10 m, (100 trees per hectare) can be tolerated. However, the ideal distance of 12x12 m or 14x14 m is recommended for grafted trees. On the other hand, wider spacing of 20x20 m and above is recommended for seeded trees.
High density planting, as experienced by most mango growers, resulted to low productivity of trees due to competition. Also, it caused problems associated with pests. Unless the tree structure is modified to accommodate small or dwarf trees, high density planting should be avoided.
Field planting
· Plant during the start of the rainy season. Planting late may be done if irrigation facilities are available.
· Plants are set in holes, deep and wide enough to accommodate the mass of soil in the roots of planting materials (usually twice the size of the container.) this is recommended in areas with fertile, deep and friable soils. However, in areas with clayey, rocky, or poor (either acidic or basic) soils, big holes with a diameter and depth of 0.5x0.5 m are appropriate.
· Provide the soil is fertile; the top fertile soil should be separated from the subsoil and should be returned first. Otherwise, this is not done because poor soil will be replaced by compost.
· Remove carefully the plastic container from the roots of the planting materials and see to it that the mass of soil remains intact with the roots.
· Mix the topsoil with 1 kg compost and place at the bottom of the hole.
· Set the plant into the hole.
· Press the topsoil with compost around the plant with feet or hands to compact.
· Tie each plant to support bamboo pole or stick to avoid lodging.
Care and maintenance of young trees
There is need to take care of newly planted trees; otherwise, high percentage mortality can occur, particularly during dry season.
The establishment period is about four to five years and its important for the trees to attain maximum canopy size, through proper management before these can be induced to flower.
a. fencing
· The whole area can be secured by a barbed wire (two strands, fixed on wooden or concrete posts).
· Individual fencing of trees can also be done using wooden sticks or bamboo poles.
· Wind breaks, if planted close to each other, can also serve as fences.
b. mulching
Mulching is needed to conserve moisture. It also serves as a source of organic matter. No prescribed amount of mulch is used but more is better.
To prepare mulch, place field waste or residues around the base of the trunk, few inches away from the stem to prevent pest problems.
Commonly used mulching materials are rice straws, rice hills, sugarcane bagasse, chopped weeds and banana stalks.
c. fertilization
Mangoes do not need extensive fertilization because they can survive in poor and unfertile soil. However, fertilization is necessary to stimulate early growth and rapid development of young trees.
Fertilizer usage depends on climate and environmental conditions, variation in farming practices, soil and tissue analyses and results of the field fertilizer experiments. Use of organic fertilizer is advised due to its macronutrients, affordability and availability.
Table 1 presents the amount and frequency of fertilizer needed at planting and during the non-bearing years.
a. intercropping
Field establishment of young trees require 4 to 5 years. To make use of the spaces in between trees, intercropping is recommended.
The types of intercrops depend upon the suitability of the commodity and their demand in the area.
· Intercrops like leguminous vegetables, melons, squash, sweet potato and short maturing fruit crops (papaya and pineapple) are recommended.
· Intercrops should be managed separately and should not compete with the main crop (mango).
b. irrigation
· Desirable climatic requirement is five months of continuous dry season that will coincide with mango flowering.
· However, there is a need to irrigate young and newly established trees, especially during the dry season.
· The volume of water required per week is 20 to 40 liters, just enough to saturate the soil within the root system.
· Flooding method can be used to apply water.
c. weed control
Weeds compete for water and nourishment of young trees. During dry season, weeds can be fire hazard and will cause the burning of trees.
For orchard plantation, weed control can be done through inter-row cultivation, using a tractor or plow driven by a cow.
For backyard plantation, ring cultivation can suffice weed control. In weeding, the following radius from the base of the trunk needs to be considered:
Age of Tree (Years) Radius (cm)
1-3 4-10
10-15 20-45
50-90 100-200
Under brush the remaining spaces manually. Use of mower or rotary grass cutter can also be done. Also, herbicide should be used with caution since mango trees are sensitive to the chemical.
d. Pruning
It is not necessary to prune young trees unless insects and disease are present, if this happens, remove only the affected parts.
In formative pruning, grafts which are about one meter tall, cut terminal portions to encourage lateral branching. Also, maintain three to four strong branches; allow them to grow before doing the second cut. This is a special pruning with the objective of producing dwarf trees.
e. deblossoming
Young trees will flower after a few years from planting. However, it is advisable to cut these flowers so as not to compete with the growth of young trees.
Management of bearing trees
With good cultural management, trees can form the maximum canopy and are ready for induction after five years from planting.
This cultural management for bearing trees will help mango growers produce more fruits of better quality.
a. pruning
Pruning is usually done after harvest to prepare the tree for production, improve fruit quality and attain desired size and shape of crown, eliminate undesirable branches and achieve dwarfing effect to enable the trees to be resistant to lodging. To avoid infection after pruning, treat the cut portion with any paint or used diesel oil.
- It is advisable to do minimal pruning prior to flower induction to remove unnecessary, crowded, overlapping branches and those which are affected by pests.
- Only the inside branches should be pruned to allow the penetration of light as well as circulation of air inside the canopy. This condition is inimical for the growth of pests.
- Some farmers do the “open center” pruning to enhance light penetration. This is recommended for big trees.
b. Fertilization
· Soil fertilizer when applied after pruning will encourage the growth of vegetative shoots, a very important requirement for flower induction.
· The amount and frequency of fertilizer is given in Table 1 for bearing trees. (see Table 1)
· For less than 30 years old grafted trees, apply fertilizer at about 1.0 to 1.5 meter radius from the trunk in a small canal constructed around the tree that is 30 cm deep.
· For large trees, make a canal perpendicular to the canopy spread and apply fertilizer.
· Developing flowers and fruits require foliar spray at 12-16, 21-25 at bud elongation and 30-35 days after flower induction to encourage development, enhance fruit set and fruit development.
c. flower induction
Flowering of mango trees usually takes place from October to May.
Growth and flowering occur in phases. Shoot or leaf flush is frequent in the juvenile stage of trees and in areas with short dry season. It is less frequent in mature trees and in areas with long dry season.
The frequency of flushes depends on cultivars; the ‘Carabao’ mango for instance has longer intervals while the ‘Indian’ mango is a regular bearer, even without induction.
· The ‘Carabao’ mango undergoes an alternate bearing habit with flowers and fruits in the first year (on season) and little or no flowers in the next year (off-season). There is a need to correct this fruiting behavior, otherwise, production becomes irregular and markets will be affected.
· The ‘Carabao’ mango ready for flower induction when leaves are 7 to 9 months old, crispy, dark green and buds are plump and prominent.
Types of Flower Induction
1. Smudging
Smudging is common practice which involves building a smoky fire below the tree canopy, allowing the smoke to pass through the foliage. It is done continuously for several days but is stopped when flowers do not appear within two weeks.
The process is repeated one to two months later. Mature trees with brittle, dark green leaves from the current flush or coppery-bronze colored from the older flush are usually preferred as well as those with prominent and well-developed terminal and axillary buds.
This method, however, is laborious and ecology-damaging. Areas around the mango orchard are not only stripped of vegetation but are polluted with combustion by-products.
2. Chemical Induction
As long as shoots are physiologically matured, potassium nitrate (KNO3) spraying can induce flowering anytime of the year. It is known that KNO3 only acts as inducing agent and “let’s go” what is inside the shoot. Hence, if shoots are not physiologically matured, leaves, instead of flowers, come out.
KNO3 is however restricted because it can be an ingredient for explosive. This holds true for other salts of nitrates, particularly calcium nitrate, which is now being used. Nitrate base in water solution offers as an alternative. (I.e. UAN and ANS)
In the absence of or failure to attain nitrate, the commercially formulated flower inducers (in powder or liquid form) may be used: Boom, Flower Set, Mangotone, Miracleblum and others.
· The success of flower induction depends on age of tree, age of shoot, month of induction, concentration of spray mixture and yield of the tree in the previous season.
· Older trees respond more readily to flower induction than younger ones.
· Flushes during the first quarter of the year may respond after seven to nine months, while the last quarter will do so in five to six months.
Tress during the wet months (July to November) need stronger concentration (2%) while the trees may respond to lower concentration (1%) during December to May.
Tress with high load of fruits in the preceding season may not respond satisfactorily to induction in the following year.
For economical reasons, it is recommended to choose carefully trees for induction. Use the following concentrations as a guide in flower induction.
For liquid formulation: Mix one liter of the formulated product in two to three kerosene cans of water (40-60 liters) early in the season. For large-scale operations, use power sprayer. For small scale spraying, knapsack or homemade, manually operated sprayer may be used.
Induced trees start to flower in 7 to 14 days. Rains of short duration immediately after spraying do not affect the effectiveness of the inducer as long as the leaves are dry when the spraying was done.
However, if continuous rain lasts for one or more days immediately after induction, follow-up spray with reduced concentration. If induced trees do not flower due to pest infestation or strong winds, postpone induction for the next season.
The percent flowering per tree also varies. This is it maximum capacity, thus, should not be forced to produce more flowers.
Note:
- In September, only trees with 10 to 12 or older shoots may respond to induction.
- In October, only old trees with seven to nine months or older shoots may respond to induction.
- In December or later, even young trees of five to six months old shoots may respond to induction.
- Central Visayas and all Mindanao regions produce off season fruits to avoid the glut in supply in March to May.
Paclobutrzol, a plant growth regulator, is used for this purpose.
The recommended season of production by region in the Philippines
Stages of flower and fruit development
Wrapping/bagging
Sixty days after flower induction is the best time to bag mango fruits, since at this stage, the fruit established on the tree.
The bag should be big enough to allow room for fruit development. Its bottom portion should be closed to prevent the mango seed borers from laying its eggs on the apex of the fruit.
Bagging, using sturdy materials, protects the fruits from the rain and strong winds. Also, it does not only promote fruit quality but also protects fruits from diseases like stem-end rot, scab and sooty mold. It minimizes incidence of fruit fly, mango seed borer or cecid fly. The practice also helps avoid latex burns during harvest, fruit rejects are reduced.
Bagging materials
Several bagging materials are used in the field. However, imported newspaper or waxy magazine is recommended for both wet and dry seasons, while ordinary newspapers may be used during dry season.
Bagged fruits have higher recovery rates and are more marketable, as compared to non-bagged fruits.
