Te Kura Horticulture
Home
Horticulture Home
Course Information
Course Information
Horticulture 1000
HT1101 - Plant management 1 - More on pruning
Pruning
5

More on pruning

The time and type of pruning varies with different plant species and will depend on what the grower wants to achieve. Some plants are pruned straight after they flower in the spring. Some plants are pruned in the winter when they have no leaves. The most common reason for pruning plants is to remove dead, diseased or damaged wood.

Fruit trees

The main aim of pruning fruit trees and vines is to increase crop production. The plant needs to get the maximum amount of sunlight to grow, flower and set fruit.

This is achieved by:

Trees are pruned in different ways depending on the branches on which they flower and produce fruit.

Deciduous fruit trees

When apple trees are pruned correctly, they are easy to manage and good quality fruit is produced. The diagram below shows you the type of branches that are removed from deciduous hardwood trees such as apples and stone fruit.

Branches to prune

      

Trees grown on espaliersTrees grown on espaliers.

Apples are sometimes grown on espaliers (wire supports), which are great for saving space in a small garden. The trees are trained along wires and constantly pruned and tied throughout the season.

Camellias and climbing roses may also be trained in this manner.

 
Grapes should be pruned during the dormant seasonGrapes should be pruned during the dormant season.

Grapes should be pruned during the dormant season.

This is when the grapes have no leaves and are resting over the winter.

Last year’s fruiting canes are cut away and new canes are tied down. The grower wants a strong framework on which the grape flowers and fruits. If the plants were not pruned they would become large and overgrown and production would be poor.

 
Summer pruning of grapes is also doneSummer pruning of grapes is also done.

Summer pruning of grapes is done to allow better sun exposure of the grape bunches. This helps to ripen the grapes and also improves air circulation, which helps to prevent disease infection.

 

Ornamental trees

Ornamental trees are pruned and trained to keep them:

When pruning or cutting out part of a tree, remember the 3 Ds. Cut out dead, damaged and  diseased wood.

Remove this wood first. Then prune the tree, being careful not to spoil its shape. If a branch spoils the form of a tree, cut it out. Older branches may need to be cut out and replaced by younger wood.

If a tree is lopsided, hard prune weak growth, and soft prune strong growth. Hard pruning stimulates vigorous new growth.

Deciduous shrubs

These are shrubs that lose their leaves in winter. Some examples are currants, hydrangeas, rose, fuchsia, lilac and azalea.

Hydrangeas have the old summer flowers cut off during the winter to encourage growth and increase flowering the following spring.

They can also be pruned to improve their shape and to keep them compact. Spring flowering plants are best pruned immediately after flowering. Summer flowering species can be pruned during the winter, when they are dormant.

When pruning a rose, cut all stems backWhen pruning a rose, cut all stems back.

When pruning a rose, cut out any thin and weak shoots and damaged and diseased stems. On bush roses, cut all stems back to 3–4 buds leaving stems around 15–20 cm high. The buds need to be outward facing.

 

Evergreen shrubs

In most cases, it is best to let an evergreen shrub develop its natural shape, as most evergreen shrubs are compact and bushy. Some need pruning after flowering to stop them getting leggy and growing at the tips and losing all growth in the centre of the plant. For example, hebes, camellia, holly and lavender. Some ground covers may need cutting back because they tend to spread too far over  paths or other plants.

Deadheading and removing dead flowers encourages new shoots and flowers.

Lavender plantLavender plant.
Pruning a lavender plant after floweringPruning a lavender plant after flowering.

Herbaceous perennials

Prune these at their tips after they begin to shoot in the late winter to help stimulate side shoots and more flowers.

Cut out any dead, diseased or damaged growth.

When plants have finished flowering in autumn, cut back to near ground level. This stimulates lush new growth in early spring.

Daisy plantsDaisy plants.

Daisy plants can be pruned after flowering to maintain their shape.

 

Activity 5A These photos show a hydrangea plant before and after pruning. Answer the three multiple-choice questions below.

A hydrangea plant before pruning
A hydrangea plant after pruning

 

Complete Activity 5B in your workbook

Complete Activity 5C in your workbook

Complete the Assessment Activity in your workbook

Key points   Key points

  • Different plants are pruned in different ways.
  • When pruning remember the 3 Ds. Cut out dead, damaged and diseased wood.
  • Many plants are pruned to produce better fruit and flowers.
  • To keep a hedge healthy, sunlight and air must be able to reach the bottom and top of the hedge.
 

What's next?

  1. Complete the self-assessment in the back of your workbook.
  2. Return your workbook to your teacher.
  3. Continue with HT1102 Plant management 2.
Pruning