Strawberries
Strawberries are not actually pruned but there are other handy tips like transplanting and cuttings.
Transplanting strawberry plants is best done in February to March. Transplant them with as much soil around them as possible to disturb the roots as little as possible. So do not shake off the soil. After two to three years, the plants need to be replaced. You can take your own cuttings or buy new plants.
The offshoots take energy away from the mother plant and this often results in less tasty strawberries. Therefore, remove the offshoots during the harvest season. Try to gain young plants only after the harvest by giving the offshoots a chance then.
The youngest strawberry plants produce the tastiest and most beautiful fruit. So for a rich strawberry harvest, rejuvenate the strawberry bed regularly. Take strawberry cuttings from the prettiest and richest-bearing strawberry plants.
Choose a few mother plants from which you will not harvest fruit but keep only for the shoots. From these mother plants, you remove just the flower buds. The offshoots closest to the mother plant will give you the best plants for next year. Therefore, take the first two plants from this mother plant at most.
The best period for taking cuttings is around mid-August. Cut off the shoots. Replant them, making sure only the roots are below ground and water them sufficiently. Plant them at a distance of 30 cm in the row and 60 cm between rows. Run the strawberries in the crop rotation. Make sure they do not come to the same spot more than once every four years.
You should also fertilise the strawberry plants. To do this, add 2 kilograms of cow manure pellets to a bucket of water. Leave this mixture for a week and stir regularly. The fertiliser will be ready for use after this week. Give the strawberry plants this liquid fertiliser every week as soon as the flower buds appear.
Blackberries
Blackberries make very long strong branches, sometimes up to 5 metres long or even longer. You will need to tie these branches to ensure that a bit of organisation remains in your plant. Moreover, it will then take up less space, dry up faster after rain and allow the sun to ripen the fruit properly. Tie the young branches in a sort of fan shape, first upwards and then sideways, to, for example, taut wires. From these comes flowering and harvesting. Meanwhile, you have already pruned away last year’s branches. Blackberries flower on the wood that grew the previous summer and autumn. It is best to prune away the old branches, which contained that year’s blackberries, after the harvest. You can easily recognise the branches by their dark brown colour, slightly weathered and shrivelled and often you can still see remnants of the bunches. If you cut away the branches that have borne blackberries every year, as close to the ground as possible, and tie up the new branches for next year’s harvest, you can never really go wrong.
Raspberries
Raspberries are always grown along wires because of their long limp stems. Raspberries bear on ground shoots that have formed the previous year. The biennial shoots die off after harvest. These dying off shoots are deeply cut away immediately after harvesting so that the young shoots have room again. After harvesting, leave about 12 per metre. The rest are cut away as deeply as possible.
In spring, around the first week of May, 6 to 8 shoots per metre are kept. Summer pruning in raspberries consists of shortening the top when it reaches height, and shortening overly exuberant side shoots.
When young raspberry plants do not form enough new ground shoots, you can encourage this by drastically cutting back the largest shoots. It promotes a well-filled row, and harvest, the following year. Mature raspberries usually produce far more shoots than you can use. When older plants barely manage to fill their rows with new shoots, they are exhausted. Then it’s better to replace them with new ones.
Pruning is a form of crop protection. Besides limiting twig death, it also removes eggs of the gall midge and rust fungus from the plants.
Japanese wineberry
The fruit of the Japanese wineberry comes on the 2-year-old wood. As a result, all branches that are in their third year should be cut off every year. Instead, the young shoots should be kept to bear fruit for the following year. Pruning can take place immediately after the wine berries are ripe. Pruning can be done from September onwards. If necessary, this can be done all winter until spring (until March). September/October is preferable. You can then very well recognise the young shoots. In spring, one-year shoots will grow again and you can tie them up again in spring.
Quince
A structure with stem and side branches is not necessary. The tree itself develops an airy crown without any intervention, which only needs to be thinned occasionally. Above all, the young shoots that have emerged at the top of the branches and grow steeply into the inner part of the crown are pruned back to their roots. Preferably do this in summer. If the shoot ever stops altogether, it can be stimulated again by light pruning. Rejuvenating older trees is also possible.
Medlar
In principle, the medlar does not need pruning. It is precisely the characteristic shape that the Medlar takes on by itself that gives it wonderful ornamental value. The tree also bears excellent fruit. So pruning the Medlar will not enhance its ornamental value. The Medlar will grow more and more vertically.
The Medlar can be pruned, but do so from November to the end of March. Remove branches growing too enthusiastically and almost vertically towards the centre of the tree, water locks. Dead wood, which is common on the medlar tree, should also be removed. Be careful, however, that the Medlar is susceptible to diseases when pruned. Pruning should always be done in dry weather and low humidity to avoid diseases.
When pruning the Medlar, bear in mind that it flowers on biennial wood. So never cut off the newest shoots. There would be no flowering and no harvest the following year.
Mulberry
The Mulberry blooms on annual wood. Therefore, in spring, last year’s shoots are pruned at 4 or 5 eyes.
During winter, all side branches are shortened to 10 to 15 cm.
New side shoots can then grow again. The mulberry should only be pruned from autumn until the beginning of winter. Pruning in summer could cause the mulberry to bleed to death. To get a mulberry with picturesque quality, the tree should be ‘trained’ as a crown on stem for the first five years. Only in the fifth year can the heart branch be removed. This gives the mulberry its gnarled and unruly appearance. After that, pruning is virtually unnecessary.
Morel
The morel bears almost exclusively on annual twigs; the older wood often remains bare. As a result, branches soon grow longer and longer, with only the tips bearing leaves and fruit. To prevent this, prune back excessively long, drooping branches to a fresh replacement. The best time is immediately after harvest.
Peach
The peach belongs to the stone fruit family.
Pruning is usually necessary not only to keep the tree low, but also to rejuvenate it. When given freedom, the peach tree grows narrowly upwards and then the lower branches die off.
If you purchase a peach tree, it will usually be an annual ooculated tree. After planting, cut off all but a few centimetres of the young twigs. The tree will then later shoot out nicely and sprout on its own. When sprouting, choose 3 or 4 shoots that are nicely divided. This way you get 3 to 4 stem branches that grow wider, with an open crown. The advantage here is that you can pick the fruit lower down later. Regrowth is also much better this way.
On the stem branches, which in turn branch out again, always remove the back shoots and only keep the side shoots. This can already be done in summer. Also always make sure that only one twig continues on the branching side, i.e. you should remove the competitors.
Peach trees should be pruned annually. This is necessary to keep the tree vital and to ensure a good harvest.
After picking, around August, prune strongly. Strong pruning gives strong growth and less fruit.
Peach bears on annual wood. After picking, prune away any shoots that have borne fruit until they reach a newly formed shoot at the base. This also makes the fruits larger and tastier. It also makes the plant more resistant to curl disease.
If not pruned, growth will move to the tip of the tree. This reduces fruit size and quality. Flavour and sugar content drops.
Make sure to keep as much young wood in the tree as possible. Of course, make sure you have an open tree and prune away the heaviest branches. Preferably prune away heavy branches after picking. This reduces the incidence of curl disease.
Pruning after picking around August – September is also the best pruning time because the chance of infection such as lead gloss is now low. The branches are then pruned back to 1/5
Remove dead and diseased branches. Always make sure the leaves are healthy and then thin as quickly as possible. The higher the leaf/fruit ratio is, the more sugars per fruit and the tastier the fruit becomes.
Pruning can also be done during flowering by cutting back the branches at 5 flowers. This way, you get enough fruit, the tree stays in good shape and you keep curl disease under control. One can slow the growth of peach trees, by pruning shortly after fruiting around May. Excess branches and twigs that do not bear fruit can then be easily pruned away. Twigs that are too heavily laden with fruit can be cut back on single fruits. Always try to leave some leaves after each fruit.
Red currant
Red currants get the best fruit on the finer lateral wood that forms on perennial wood. Shrubs are raised with a fixed trunk. Free-standing bushes are grown up vase-shaped. Usually you let the shrub emerge from the ground with several stems. Three is a good base; more stems from the ground quickly make the shrub look untidy. These three stems should be branched shortly above the ground to form six stem branches. The aim is to have the branches facing outwards, so that the middle of the bush remains open. This vase shape allows sunlight to penetrate the crown optimally. The coarser sidewood that develops on these branches is cut back briefly to encourage the growth of finer shoots.
Rejuvenate the fruiting wood by replacing one of the stem branches entirely with a newly grown one over time, after harvesting. The side shoots on red currant can then last for years.
Sweet chestnut
Sweet chestnut can be deeply pruned back, but pruning is usually unnecessary.
Pruning is only necessary to guide the main shape of the tree. Basically, a main spindle with side branches is assumed. Only the best side shoots are retained. The remaining and weak shoots are pruned away smoothly near the trunk. Allow plenty of light and sunlight to enter the tree.
Sweet chestnut is pruned in the dormant period, autumn or winter. Summer pruning can be carried out in summer. This pruning focuses on keeping excessively long shoots in shape or within limits or pruning away / shortening shoots that simply obstruct passage. Fully grown specimens hardly need any pruning. Colourful varieties are checked in summer for ‘wrong’ shoots. These are shoots that do not have coloured leaves.
In old trees, it is sometimes necessary to rejuvenate the top. The top is cut out so that new side shoots and possibly a new top can form. Old trees carry the danger of branches falling out unexpectedly.
Walnut
A walnut should be pruned as little as possible. If pruning is necessary, limit the pruning to removing dead wood and adjusting the crown shape or structure. A Walnut tree actually prunes itself. Dead branches fall out naturally after two years.
The best time to prune is from the beginning of June to the beginning of September at the latest, when the tree is fully-grown and in leaf. This gives the best wound healing and good regrowth, so that the tree enters the winter in a good state of balance. The reason for this is that in the case of the walnut, the sap flow is now continuous. This has occurred only in the last 10 years (2013) due to climate change. Pruning at a later time makes the tree extremely vulnerable to frost damage. Moreover, there is little chance of pathogens entering during this period, as the walnut has the greatest resistance during the growing season. [Walnut tree bleeding in spring; 31 March 2018]
There is even more disagreement among experts about pruning in walnuts than in other fruit trees, and that’s saying something !
In 2015, research indicated that pruning in August resulted in no visible wound healing. Bleeding could even occur in December. This research showed that pruning wounds heal fastest at the time when the tree is making new roots and annual shoots, and that is in spring.
For pruning, start young and intervene often but moderately. Removing branches that are still alive is poorly tolerated by the walnut. It can only be done if the branches are no thicker than 5 cm. The tree will bleed excessively with a high risk of parts of the tree dying. Larger wounds therefore heal poorly and often rot. Remove thicker branches only when they have died.
When pruning, it is important not to leave stumps in place, they will die off.
Never prune back into perennial wood. Buds on perennial wood are very difficult or impossible to bud.
If they bleed, it is very likely that they have been pruned incorrectly or at the wrong time. This bleeding can be stopped by spreading a mixture of cow manure + clay/loam + lime over the wound. Also, in spring the root pressure can become so high that spontaneous bleeding can occur. This will go away by itself.
As long as the wound is bleeding, it cannot be treated. By the way, the layer of moisture on the wound is a breeding ground for bacteria and fungi. Wounds left untreated in August often show cracks in winter.
Black currant
Blackcurrant bears on annual wood, the berries come on shoots that grew the previous year. The short side branches of older shoots produce smaller clusters with smaller berries; the sturdy annual shoots produce more and better-developed clusters. Therefore, after harvesting, all shoots with berries on them are usually pruned away. What remains are the shoots that have grown this year. The best developed of these are kept. On older wood, the growth of side shoots becomes finer and finer, and berries become smaller and less sweet.
It is not necessarily necessary to prune all fruit branches, you can also leave some that have developed strong shoots. Only the top part of these shoots should be pruned back to a vigorously developed young shoot.
After pruning, blackcurrants should consist of at least 3/4 of young shoots. Do not let the blackcurrant emerge with too many stems either, as the foliage will quickly become too dense. Keep five or six stem branches and prune them from ± 10 cm. above the ground. This gives you a bush that is still sufficiently open at the bottom for the necessary ventilation.
Mulberry blooms on annual wood. Therefore, in spring the shoots from the previous year are pruned at 4 or 5 eyes.
During winter, all side branches are shortened to 10 to 15 cm.
New side shoots can then grow again. The mulberry should only be pruned from autumn until the beginning of winter. Pruning in summer could cause the mulberry to bleed to death. To get a mulberry with picturesque quality, the tree should be ‘trained’ as a crown on stem for the first five years. Only in the fifth year can the heart branch be removed. This gives the mulberry its gnarled and unruly appearance. After that, pruning is virtually unnecessary.
This post has been translated by Deepl, so there may be some inconsistencies in the text.