It is a simple process of cutting extra and unwanted branches, buds, or vegetative growth of a plant.
Pruning can be done via removing or cutting unnecessary growth of plants, removing damaged tissues, removing broken branches, maintaining a balance between vegetative growth and fruiting capacity.
What is pruning
Pruning is the process of removing unwanted branches to support plant growth by allowing proper sunlight to produce a high yield.
Please note that avoid removing too many branches and so reduce potential fruit yield.
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The basic steps of pruning are as follows:
- Start pruning at the top
- After top pruning, work downwards.
- To strength central leader cut upward growing branches.
- Remove dead, broken parts.
- Change direction or divert branches to open areas.
- Remove the crowding branches and free up some space.
- Cut dense branches to allow proper sunlight.
- Remove parallel growing shoots causing crowding and shading.
- Also cut opposite growing shoots at a point on the stem.
- Divert branches to open areas by pruning to desirable laterals.
What is Training and Pruning
Training and pruning are two important functions or phases of a high-density apple orchard.
The training concept is a simple but important aspect in which the plants are trained to establish a strong framework and foundation of the plants of scaffold limbs capable of supporting heavy yield.
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By training and pruning, we can provide or regulate it to allow a maximum amount of sunlight, an annual succession of crops, expose maximum leaf surface to the sun, and direct the growth of the trees.
These two methods are also beneficial in other ways, it reduces the amount of labor and other economic expenses such as spraying and fertilizers.
Mature Tree Pruning
As the orchard reaches maturity, the pruning should be able to allow the maximum possible sunlight within the allotted space.
Also by this process, the sunlight much reaches the lower ends or branches of the tree to provide good light distribution as this led to good fruit quality.
An important part of pruning is the top of the tree is kept narrower than the bottom of the tree and to make sure that there is a good balance between vegetative growth and cropping.
Pruning strategies based on shortening or stubbing back permanent branches that outgrow their allotted space generally are not as successful as limb renewal pruning strategies.
This is partly because the most productive fruiting wood is cut off when a branch is shortened.
In addition, stubbing cuts stimulate localized vigor on the affected branches which results in shading of the lower canopy.
A more successful approach has been to annually remove 1-2 large upper branches completely and develop younger replacement branches.
This “limb renewal” pruning is the single most important pruning concept for mature high-density orchards to contain the canopy and maintain a conic tree shape.
To assure the development of a replacement branch, the large branch should be removed with an angled or beveled cut so that a small stub of the lower portion of the branch remains.
From this stub, a flat weak replacement branch often grows. If these are left un-headed they will naturally bend down with the crop.
They are naturally shorter than the bottom branches thus maintaining the conic shape of the tree without stubbing cuts.
This type of pruning does not stimulate vigorous regrowth. Our recommendation is to begin removing 1-2 whole limbs in the top of the tree once the tree is mature (years 6-7).
This allows moderate pruning each year and a method to contain tree size. It also maintains good light distribution in the canopy without inducing excessive vigor.
On trees with overgrown tops that need to be restructured, moderate renewal pruning (1-2 large upper branches annually) for a 4-5 year period can eliminate all of the large branches in the top of the tree.
Once branches have become horizontal or pendant under the weight of the crop, they can be shortened by heading cuts without adverse effects since the terminal bud no longer exerts significant control over the branch.
The natural bending of branches under the weight of fruit without heading can be used to great horticultural advantage in the tops of vigorous trees when it is desired to limit tree height.
Often growers want to limit tree height by heading the leader at the top of the tree. If heading cuts are made on vertical shoots in the top of trees, vigorous regrowth results.
If lateral shoots or limbs are manually bent horizontal or allowed to bend naturally under the weight of the crop they set heavy crops the next year.
Precautions in pruning
- When the limb larger than 3 cm in diameter is removed, the pruning cut should be made as close as possible to the branch from which the limb arises without leaving a stub.
- Large pruning wounds should be protected with Bordeaux paste or Chaubattia paste to check the entry of rot causing fungi.
- In 1 or 2 year old shoots, heading back can be done to promote growth of side shoots and quick wound healing.
- In 3 years old and older shoots, pruning should be shifted to thinning out cuts to reduce vegetative growth and promote fruiting.
- The competing branches should be thinned out rather than headed back.
Branch Angle Manipulation
An important method of shifting the balance between vegetative growth and cropping in young trees is tying down of the scaffold branches below horizontal to induce cropping.
In the vertical position, a shoot grows more vigorously than in a horizontal or pendant position and tends to remain non-fruitful.
A horizontal or pendant limb grows less vigorously and then crop heavily the next year and bend under the weight of the fruit.
The fruits are also strong competitors for resources and limit the growth of the branch even more.
If a vertical limb is manually bent horizontally, lateral buds are released from dormancy. If the vigor of the branch is excessive, these buds may grow into vigorous upright shoots themselves and remain unfruitful.
However, if the branch has more moderate vigor, the lateral buds grow into short shoots which become fruitful.
High yield and high fruit quality can be achieved with a high-density orchard when the orchard has good light distribution throughout the tree canopy and there is a balance between vegetative growth and cropping.