Cherry trees tend to grow a lot – even to a height of over 6-8 metres in some varieties. While it is, therefore, necessary to contain the vigour of the foliage with constant pruning, knowing how and when to prune the trees is also very important.
This activity also helps maintain a plentiful production of cherries, especially in the lower part of the tree, where the fruit is easier to harvest. Cherry trees, however, find it difficult to heal wounds; therefore, it is advisable not to let the branches’ diameter get too big before they are cut. The right time is when the plant has already borne fruit, but has not yet gone into vegetative rest, or immediately before the spring awakening.
In cherry trees, one pruning leads to another, but with the right tools
We all know that cherries are very moreish: once you’ve popped one in your mouth it’s difficult to stop. By extension, we could also say that, when it comes to pruning the tree that produces this beautiful red and juicy fruit, one pruning must lead to another. The plant bears fruit mainly on two-year-old wood; it, therefore, tends to move production to the terminal part of the branch, at the top. Hence the need to limit production on young shoots, which bear better fruit and from which it is also easier to pick cherries. For production purposes, it is estimated that it would be appropriate to renew around 20% of the branches every year, as well as eliminating old ones or those broken by the wind. More vigorous pruning is practised above all on very productive cultivars to obtain fewer but larger cherries.
The cherry tree, however, is a very delicate plant from a phytosanitary point of view and heals wounds slowly with a greater risk of succumbing to disease. In particular, it tends to react to injuries suffered or infections with the condition known as gummosis, i.e., that (you guessed it) gummy substance that forms when the lymph exudes from the bark.
Therefore, it is necessary to perform this operation carefully and with a light hand, without making drastic cuts all at once, for example in the case of reform pruning; it is, perhaps, better to distribute the cuts over several seasonal interventions, also so as not to stress the development of the vegetative part of the plant too much to the detriment of the productive part. In any case, it would be advisable to ensure that you do not have to make cuts on branches with a diameter of more than 4-5 centimetres.
At the same time, how the cherry tree is pruned is also important. It is necessary to respect the bark collar and make angled cuts (to about 45 degrees) to prevent humidity and rainwater from stagnating. Above all, it is necessary to make clean and precise cuts so as not to leave burrs on the bark that are more difficult to heal. Good pruning, therefore, involves more than the operator’s technical skill alone; it also requires the use of hand pruning tools of excellent quality, such as shears, loppers and saws with blades made of highly resistant forged steel produced by Campagnola.
Lastly, it is advisable to frequently disinfect cutting tools, especially after removing diseased branches, and even newly pruned ones, perhaps by immediately spreading propolis on the largest ”wounds”, or by subjecting the entire tree to a preventive treatment with copper after the leaves have fallen.
Sweet and sour cherries
There are different varieties of cherry, which are mainly divided into sweet and sour. This distinction is followed by others, based on the type of fruit produced.
Two varietal groups stand out among sweet cherry trees: ”duroni”, which are cherries with a hard and fleshy pulp that are almost crunchy, and heart-shaped cherries, which instead have a soft pulp. Both are also further broken down into light-fleshed and dark-fleshed cherries, based on their colour.
Sour cherry trees, on the other hand, fall under three varietal groups: “visciole”, which bear spherical fruit with a sour flavour, “maresche”, whose fruit is small, bitter and acidic, and “amarene” (the fruit that in English would be known as “sour cherries”), which bear large fruit, depressed at the poles, and with a sweetish taste.
Choosing the cultivation form of cherry trees
Sweet and sour cherry tree varieties differ not only in the characteristics of the fruit, but also in how they adapt to the climate and soil. Sweet cherry trees are hardy when it comes to the winter cold and adapt to soil poor in nutrients, as long as it is not too dry; sour cherry trees, on the other hand, adapt better to humid environments and clayey soils. But they also differ in the shape of the plant. Sweet cherry trees, in fact, are erect-rising and tend to grow very tall if left to their own devices. Conversely, sour cherry trees are generally smaller and bush-like.
There is also a substantial difference in the prevalent production branches. The cultivars of the sweet cherry tree group bear fruit on the flowering shoot, also known as “May bunch”, while the cultivars of the sour cherry group bear fruit mainly on medium mixed branches and mixed twigs.
Starting from the characteristics of each variety, it is possible to choose the form of cherry cultivation that can be most productive in terms of quality and quantity. The choice is essentially limited to two options, which are the most used in orchards: the low vase shape and what is known as the palmette shape.
The low vase cultivation form
The low vase cultivation form, widely used on hilly terrains, makes it possible to limit the height of the cherry plant to between 2 and 2.5 metres. It involves a rod, shortened immediately after planting to a height of about 50-60 centimetres from the ground. Then 3 or 4 main branches develop from the central stem over a period of three to four years. After the first year, in fact, having eliminated branches that grow too low, the ones born from the first shoots are selected, spurred at 70-80 centimetres from the ground, leaving 4 or 5 buds on each. The branches developed from these buds will, in turn, be spurred the following year. In the third year of cultivation, the shoots will only be thinned out, eliminating those that are too vigorous and vertical. And from the fourth year on, it will only be necessary to make return cuts to maintain the low vase shape.
The palmette cultivation form
The palmette cultivation form is mainly used in flat terrains and in the more intensive and mechanised orchards and takes 3 or 4 years to achieve. The orchard is organised in rows which have a structure made up of horizontal poles and metal support wires, to which the branches are tied. The high wall system also makes it possible to contain the effects of spring frosts.
Cherry trees in palmette cultivation develop on 3 or 4 shoots of branches, which branch out on both sides from a scion, which sprouts about 60 cm from the ground. The first shoot has a height from the ground slightly higher than the scion with branches angled at 45 degrees. The second shoot is approximately one metre above the first, with less inclined branches, and the third shoot is at a height of approximately 70-80 cm from the second with even less inclined branches. During the formation of the shoots, the branches are left to grow, limiting the vegetation of the other branches; most importantly, the branches that try to develop in the inter-row space are shortened.
Summer and winter green pruning
As cherry trees are very delicate plants, it is preferable to prune them as soon as the fruits are harvested. Therefore, summer pruning is recommended when a lot of sap is still circulating in the plant and the wounds left by pruning cuts can heal more quickly. Indicatively, the right period for pruning starts after the fruit harvest and lasts until September, just before the leaves fall and vegetative rest begins.
You can also prune the cherry tree at the end of winter and at the beginning of the spring awakening, between February and March; in this case, however, it is necessary to be on time, since cherry trees bloom very early (white flowers), generally between March and April, and the budding branches must absolutely not be cut.
Winter pruning is usually practised during the growing years to encourage vegetative development and therefore the growth of the plant, while summer green pruning is practised during the production period, or if it is necessary to reshape the plant, bringing back the foliage to smaller dimensions.
How to prune cherry trees in production
The criteria for pruning vary depending on whether the plant is in cultivation or in production, and the necessary tools are also partly different. We have already discussed which technique must be used to carry out cultivation pruning. When it comes to tools, tender branches of a small diameter can also be easily pruned with hand tools, such as Campagnola double-cut hand shears model S2, or S25 fixed-bladed hand saw , but if the orchard is large, you can opt for electric shears with plug-in battery, such as Stark M, or Star 30 pneumatic model, which reduce operator fatigue.
With production pruning, it is, first and foremost, necessary to ensure “air” and “light” for the cherry trees, as is the case for all fruit trees. Branches that are broken and/or attacked by diseases, the basal shoots and the suckers rising on the branches must therefore be removed. Generally, all excess vegetation or branches that intersect each other must be thinned out, to ensure good air circulation inside the plant and that the sun’s rays penetrate well, to keep the cherry tree healthy, preventing the attack of parasites and the onset of diseases. Shortening the productive branches and removing the exhausted fruit branches facilitates the renewal of the May bunches and mixed branches, to keep the production and size of the cherries constant.
If pruning has been constant and carried out regularly every year, large diameter branches will not have to be cut even during the production phase and you can keep using the same tools used during the cultivation period. Since the plant will certainly have grown in height, it will, however, be a good idea to also equip yourself with hand loppers, such as Campagnola S20 straight anvil-cut model, or electric chain pruners with plug-in battery, such as T-Rex, or with backpack battery, like Kronos 58, also on an extension pole.
Campagnola tools
Campagnola catalogue, which can also be browsed online, features many other tools, having all Made in Italy quality and suitable for good pruning.
The hand shears (PROFESSIONAL Line) have hot-forged steel blades, ergonomic handles, are lightweight (around 230 grams) and make for cuts of up to 25-28 millimetres in diameter.
The range of electric shears with lithium-ion plug-in battery also includes Speedy, Stark 90 (on extension pole) and Stark L (GREEN Line) for cuts up to 38 mm in diameter. Among electric chain pruners with plug-in battery, T-CAT M and T-FOX (GREEN Line) models stand out.
Operators who prefer pneumatic tools, on the other hand, find ideal work companions in tools powered by compressed air generated by engine-driven compressors, also mounted on the tractor or trailer, and PTO compressors. The shears of PROFESSIONAL Line Star 40, Star 50, Super Star doppio taglio (with double-cut blades), all with body made of technopolymer , and Victory, with body made of technopolymer with carbon fibres, are equipped with blades made of highly resistant forged steel . Similarly to the Laser and Linx chain pruners (PROFESSIONAL Line) they are characterised by the absence of vibrations and kickback, as well as low weight, handiness and high efficiency even in intensive use.
All Campagnola products are available from a vast network of local distributors, also able to provide support and original spare parts.