From the Manual Of Tropical And Subtropical Fruits
amount of pruning required by the avocado depends largely on the
variety. Some make short stocky growths and form shapely trees without
the assistance of the pruning-shears, while others take long straggling
shapes and do not branch sufficiently to form a good crown. These
latter must be cut back heavily. Trapp, and other varieties of the West
Indian race in general, usually make low stocky trees, branching
abundantly and forming plenty of fruiting wood. With such forms,
pruning is reduced to the minimum, consisting principally in removing
fruit-spurs which die back after the crop has been harvested, and in
the occasional cutting back of a branch to produce a crown of
symmetrical form and good proportions. Beyond this very little pruning
is done in Florida orchards.
With the Guatemalan
race, more training is often necessary to produce a tree of ideal
proportions, since some varieties tend to make long unbranched growths.
In others the lateral branches are very weak and scarcely able to bear
their own weight if allowed to develop unhindered. With these, careful
attention should be given during the first few years to producing a
well balanced tree capable of carrying good crops of fruit.
Mexican race usually shows a tendency to grow more stiffly erect than
the others, and make stout rigid branches which are capable of bearing
heavy crops. In order to keep some of these varieties from becoming too
tall and slender, it is necessary to top them when young, perhaps
pinching out the buds of the main branches later on to induce branching.
is not desirable to have the crown so dense that light will not reach
all parts freely. When the crown is too thick, fruit is produced only
on its outer surface, and much of the fruit-bearing capacity of the
tree is thus wasted.
it can be seen
that no specific rules for pruning, covering all varieties, can be laid
down, other than that the object should be to produce a tree having a
broad, strong, well-branched crown of good proportions and great
fruiting capacity, preferably headed low (about 30 inches above the
ground), in order to shade the soil beneath it. After the tree has
reached maturity little pruning is required, provided it has had the
benefit of careful training during the first few years. Experience
along this line is meager, however, and the future will bring out many
new points of importance.
seedlings, it is often necessary to cut off large
limbs. The stubs should be smoothed off and covered with a coating of
grafting-wax. The same rule applies to cuts made in the course of
ordinary pruning with young as well as old trees. When secondary
branches are removed, they should be cut as close to their junction
with the main branch as possible, and the cut should be parallel with
the main branch. The cut surface should be treated with a coating of
grafting-wax. Paint is sometimes used for this purpose, but in Florida
it has been found injurious, especially to young trees. If the stubs
are not waxed, they often allow fungi to start and destroy the wood.
The entrance of such fungi is facilitated by the fact that the pith
sinks in the cut ends of large limbs, leaving a small cavity to collect
water and maintain the moist conditions which are so favorable to
differ as to the best time for pruning. In Florida late fall and
winter, November to February, have proved suitable. In California the
best growers seem to favor spring or fall. According to Krome, pruning
in hot weather often results in serious injury. The most favorable
times seem to be early spring, before growth has commenced and before
the heat of summer, and autumn after hot weather is past.