More Flowers = More Fruit
What do you do if your Mango isn't fruiting?
Not all mature Mango varieties produce fruit every year and some stubborn trees are plenty mature but still won't flower no matter how much we want them to. Lucky for us, there is a very interesting way to encourage a Mango tree to flower (besides regular pruning). Let's discuss...
Many varieties of mango trees naturally produce fruit every other year; during the "off" year, the crop may be very small or even nonexistent. The use of flower inducers stimulates flower growth during the resting year so the tree produces annually. Flower inducers can also increase the number of viable blooms during the natural fruit-producing year, for an increase in production; they can also be used on varieties that provide a crop every year, to boost harvest. The inducers work best on healthy, mature trees that are under 10 years of age.
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So, what's the secret sauce?
Potassium nitrate (KNO).
KNO is a flower inducer that contains potash and nitrogen, needed for flower growth. Choose an overcast day where there is no rain forecast, to allow time for the chemicals to absorb into the tree without scalding the leaves. Spray a low dose of 1 to 2 percent KNO to water directly on the tree leaves when the buds are dormant, from December through May. Repeat the spraying two days after the first application. Adding Apsa-80 to the solution helps it stick to the leaves for faster absorption.
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Another option is Calcium nitrate (CaN), which contains 45 percent calcium to induce flowering in mango trees. This chemical treatment is a lower cost option than KNO for stimulating flower growth. Spray a dose of 2 to 3 percent CaN to water directly on the leaves of mature mango trees during the months of December through May. Repeat the application of CaN two days after the first. Add Apsa-80 to the solution to help the flower inducer stick to the leaves for absorption. Apply CaN on an overcast day when there is no rain in the forecast for at least two days following the application.
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Of course, a good ol' high Nitrogen fertlilizer does wonders too. Fertilize mango trees with a nitrogen tree fertilizer for citrus fruit-bearing trees to stimulate flower production and healthy tree growth. Organic fertilizers have a lower risk of burning the shallow root system. Apply the fertilizer early in the season, before mid-summer, for best results with inducing flowers. Sandy soils drain quickly and might require an extra half dose of fertilizer with each treatment if new growth is slow. Flower inducers sprayed onto the tree are needed in addition to a soil applied fertilizer.
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