With modern growing techniques for fruit trees such as grafting and dwarfing, home gardeners are now able to grow fruit trees in a wide variety of climates and in smaller areas such as home patios. Pruning and training fruit trees are two of the best care practices to improve the fruit tree’s fruiting capabilities and overall health.
Growth Patterns
The size of a fruit tree is often measured by the type of rootstock such as dwarf, semi-dwarf and standard. Dwarf fruit trees produce fruit sooner than standard types at around 2-5 years old, but need to be trained and pruned more regularly. Standard rootstocks produce large trees that vigorously fruit after 5-7 years or more and need little pruning.
Check the chilling requirements for your trees. Hardy fruit trees such as apples, pears and plums need a certain period of cold temperatures below 45°F in the winter to flower and fruit the following growing season. These are referred to as ‘chill hours’. Different varieties of the same species can be bred to have different chill hours based on where they are most hardy. For example, cultivars bred for warmer climates will have a lower chill hour requirement and cultivars bred for colder climates will have a higher chill hour requirement. Find your plant hardiness zone here.
Grafting
Fruit trees are not usually propagated from seed or cuttings because they do not usually grow to be a true form from the tree they came from. Instead, trees are grafted. Grafting is the joining of two trees. The base and roots are the rootstock and the top growth is the scion. The rootstock is a known hardy cultivar that determines the growth rate and maturity size of the tree.The scion is a more desirable cultivar that determines the fruit quality the tree will produce. Grafting is also beneficial for growing fruit tree cultivars that would not normally do well in the soils of that region. These desired cultivars are grafted onto a rootstock more compatible with that soil.
Grafting the scion to the rootstock allows the tree to keep the hardy traits such as pest and disease resistance from the rootstock while producing high quality fruit. The graft union can usually be seen at the base of the plant. It looks like a kink or swollen area in the trunk.
Tip: If you have not already purchased your tree or are thinking about buying more, ensure you are buying from reputable sellers who are able to provide you information about the rootstock.
Benefits of Pruning
Pruning and training fruiting trees is important for the overall health of the plant to maximize fruit yields and for the overall aesthetic appearance of the plant.
Most of the pruning that is done to young trees that are 1-3 years old is mainly done to train the shape of the tree. This includes training one central leader by removing competing leaders, to influence the direction of lateral growth and to develop a strong framework. Hard pruning young plants under three years old should be avoided in order to allow the plants to produce more vigorous growth.
Fruit trees are very prone to diseases and insect infestations, so pruning to open up the canopy allows for better airflow which will create a less than ideal environment for diseases and insects. Opening up the canopy will also allow for better sunlight penetration so inner growth does not get shaded out.
If your established tree is not producing fruit or fruit production has declined over the years, a lack of pruning could be a factor. The weaker the growth is on the tree, the weaker the fruit production will be. Fruit trees respond well to being pruned and often respond with healthier, more vigorous growth.
Types of Fruiting Trees
Apples
Hardiness zones: 3-9
Chill hours: 500-1000
Flower: Mid spring
Prune: Late winter to early spring
Pears
Hardiness zones: 4-9
Chill hours: 200 - 800
Flower: Early spring
Prune: Late winter to early spring
Plums
Hardiness zones: 5-9
Chill hours: 700-1000
Flower: Early spring
Prune: Early spring to mid summer
Sweet and sour cherries
Hardiness zones: 4-8
Sweet chill hours: 700-800
Sour chill hours: 1200
Flower: Early spring
Prune: Late spring to early summer
Peaches and nectarines
Hardiness zones: 5-10
Chill hours: 100-200
Flower: Early to late spring
Prune: Late winter to early spring
Apricots
Hardiness zones: 4-10
Chill hours: 500
Flower: Early spring
Prune: Summer
Citrus
Hardiness zones: 9-11
Chill hours: none
Flower: All year
Prune: Anytime in warm climates, Spring in cold climates
How to Prune
Before beginning to prune, first make a plan to reduce the chances of making mistakes. Even if mistakes do occur, the plant will eventually grow out and the mistakes can be corrected in future seasons. Fruit trees are very susceptible to fungal and viral infections, so it is important that all of your pruning tools are disinfected prior to making any cuts.
Making correct cuts will help eliminate the chances of disease. All cuts should be clean cuts made at a slight angle and as close to the next branch as possible. Slight angles prevent moisture from pooling on top of the wound and influence the direction of the new growth. Using sharp pruning tools will help eliminate damage to the plant tissue.
To help you determine how much to prune, the general rule is to prune weak growth hard and strong growth lightly. Lightly pruning each year will help eliminate the need to heavily prune. If your tree is very overgrown or needs to be renovated to reshape the plant, avoid pruning more than ¼ of the canopy in a year. Instead, space out hard pruning over a few years to reduce stress to the plant and reduce excessive regrowth. The harder you prune, the more vigorous the growth will come back. Keep in mind that hard pruning will result in fewer fruits, but will promote more fruiting in the following seasons. A lack of pruning altogether will result in many small fruits.
Pruning Tools You Will Need
Pruning Steps
Step 1: Remove dead, damaged or diseased branches.
Stems that are severely diseased or dead will prevent further spread of unhealthy conditions such as fungal spores and homes for insects.
Step 2: Remove rubbing or crossing branches.
Crossing stems can rub against other stems, creating wounds that are susceptible to disease and insect infestations.
Step 3: Remove inward growing branches.
Removing inward growing stems opens up the canopy for better air flow and light penetration
Step 3: Remove downward pointing branches.
This growth can get shaded out or will rub against other branches.
Step 4: Prune back weak branches to the next healthiest node/leaf set.
To influence the direction of a shoot to grow outwards, cut right above a bud that is on the outside of the stem.
Step 5: Prune off suckers.
These grow from the base of the plant and grow more frequently with more pruning as a stress response.
Other proper care tasks for fruit trees such as fertilizing, pest management and watering are important factors that affect the growth and fruiting potential of fruit trees. For further care tips or questions on pruning fruit trees, we will be happy to assist you in a virtual telehealth appointment with one of our Plant Specialists. Please click on one of the options below to book an appointment.