The art and science of pruning takes time and thought. Before making your first cut, study the tree’s potential size and natural shape, and imagine how it might appear in three to four years. Try to maintain that shape in your mind as you prune. This will help you to make difficult decisions associated with pruning. The recommended tree height for tropical fruit trees varies depending upon the species and sometimes the cultivar, but 8-15 feet tall and 15 feet wide would be ideal.
Tropical fruit trees should be pruned for the following reasons:
To control their size and shape and maintain fruit production in the lower tree canopy:
In order to maintain fruit production in a tree’s lower canopy, it must be exposed to sufficient light. When fruit trees are allowed to grow too tall or to become shaded by adjacent trees, the lower canopy will be lost and only the middle or top of the tree will flower and set fruit. To prevent this, fruit trees should be pruned annually or biannually. Tall trees are also much harder to harvest. If a tree is kept at a manageable height, harvesting the fruit will be much easier. Don’t remove more than 25% of the tree’s canopy when you prune it.

To remove unhealthy portions of the trees:
Crossed branches and dead wood should be removed. When dealing with crossed branches, remove the smaller of the two branches. Dead wood can be an entry point for pathogens and insects and should be eliminated.
To reduce the likelihood they will fall or break apart during a tropical storm:
Smaller, more compact trees are less likely to go down in a storm. If the tree is open to sunlight and air, it will also be less likely to fall.
When should I prune my fruit tree?
This is the question I get the most when it comes to pruning. The rule of thumb when pruning tropical fruit trees is to prune the tree just after you harvest the last fruit. If your mango tree is done giving fruit in late July, that would be the best time to prune. This will allow the tree to successfully recover from the pruning and the bloom cycle will not be disrupted. If you were to prune in November, this would cause the tree to produce leaves instead of flowers.
Tools to use
Hand Pruner: this is the one tool a gardener cannot live without. It is always good to have one on hand when walking your yard in case you see something that needs immediate attention. The hand pruner can be used to cut branches ¾ of an inch and smaller. Larger cuts are made with a lopper or a saw. The hand pruner should be made of high-grade metal and should be able to be taken apart to be cleaned and sharpened. Make sure individual parts are available for sale for your pruner before you buy it. That way if a part goes bad on your tool, you can just replace it rather than getting rid of the entire tool.
Lopper: this tool is used for branches ¾ of an inch to two inches. The tool handles should be made of a durable material and the blade should be able to be sharpened and cleaned with little difficulty.
Hand Saw: the hand saw is used to cut branches two inches and larger. Look for teeth that are sharpened alternately. The saw should have a gentle arc from handle to blade which allows the saw to grip or “bite” into the branch being cut. The saw should not fold, as folding saws will sometimes collapse when you are working resulting in injury.