Deciduous Fruit Trees Need Pruning

Prune now for better peaches later.

Many plants should get most of the pruning they need while they are dormant in winter. Such pruning is less stressful because it happens while plants are naturally sedated. Some plants that need aggressive pruning during their winter dormancy may need no other pruning until the following winter. Most deciduous fruit trees conform to this category. Their pruning is rigorous and specialized.

The innately aggressive pruning that deciduous fruit trees require may seem to be brutally unnatural, but is very justifiable. It is necessary to compensate for unnatural production. After centuries of selective breeding, most deciduous fruit trees produce more fruit than they can support. Their fruit is unnaturally abundant, unnaturally bulky, or both. Such improvement has distinct consequences.

Unlike their wild ancestry, many modern deciduous fruit trees would not thrive for long without intervention. The weight of their fruit eventually breaks and disfigures limbs. Such breakage exposes sensitive bark to sun scald, and leaves wounds open to decay. Insect and disease pathogens proliferate in deteriorating growth. Furthermore, messy excess and unreachable fruit attracts vermin.

Pruning improves the structural integrity of deciduous fruit trees so that they can support their fruit. It also concentrates resources into fewer fruits of superior quality, rather than allowing production of inferior surplus. Invigorated vegetative growth is more resilient to pathogens. Proper pruning removes dead, dying, damaged and diseased growth, the ‘four Ds’, as well as unreachable growth.

The main categories of deciduous fruit trees are stone fruits and pomme fruits. Stone fruits are of the genus Prunus. They include peach, nectarine, apricot, plum, prune, cherry, their hybrids, and almond. (Almonds are the ‘stones’ of their fruits.) Pomme fruits are apple, pear and quince. Peaches need more aggressive pruning than cherries, simply because their fruits are so much bigger.

Pomegranate, persimmon and fig also need specialized pruning while dormant through winter.

Prune Fruit Trees While Dormant

Dormant fruit trees should be pruned aggressively.

After centuries of breeding for abundant production of unnaturally large fruit, deciduous fruit trees have become dependent on specialized pruning while they are dormant through winter. Without pruning, most eventually become overgrown and overwhelmed by their own fruit. The weight of excessive fruit disfigures and breaks limbs. Pathogens proliferate within distressed foliage, crowded fruit and surplus fruit that falls to the ground.

Pruning not only improves the structural integrity of the limbs, but also limits the production and weight of the fruit that will be produced. Limiting production concentrates resources, so that there are fewer, but considerably better fruits, instead of too many inferior fruits. Concentrating the growth of the fewer new stems that develop in spring promotes vigorous growth that is more resistant to pathogens. Ideally, pruning also limits the height of fruit trees, so that much of the fruit develops closer to the ground.

Peaches, nectarines, apricots, plums, prunes, and cherries are all relates ‘stone’ fruits (of the genus Prunus), so require various degrees of similar pruning. Peach trees produce the heaviest fruit, so need the most aggressive pruning. Cherries trees produce significantly lighter and smaller fruit, so get pruned relatively minimally. Almonds (which are actually the ‘pits’ of a similar type of stone fruit) get shaken from their trees, so there is no advantage to keeping production close to the ground.

The ‘four Ds,’ which are ‘Dead, Dying, Diseased and Damaged’ stems should be pruned out first. Then the vigorous stems that grew last year should be thinned and cut back, but not removed completely. They are the stems that will bloom and develop fruit the following year. Pomme fruits, such as apples, pears and quinces, develop on similar newer stems that should likewise be pruned down, but many also develop on lower ‘spur’ stems that elongate so slowly that many spurs may never need to be pruned.

Most young deciduous fruit trees will need more pruning each year as they grow. Fortunately, pruning becomes more familiar with experience. Because pruning fruit trees is so specialized and important, it is worth studying more thoroughly.

Fruit Trees Need Specialized Pruning

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Even almond trees need some pruning.

For centuries, fruit trees have been bred to produce unnaturally abundant and unnaturally big fruit. That has worked out well for those who enjoy the resulting fruit. It is not such an advantage for the exploited trees that must produce it. Without specialized pruning, most of such trees are unable to sustain healthy development of all the fruit they could potentially produce, or support the weight.

Specialized pruning concentrates resources into less excessive fruit of superior quality. It improves structural integrity of limbs that support the weight of all the fruit too. Trees that produce smaller and lighter fruit, such as cherries, may only need to be trimmed occasionally to eliminate structurally deficient growth. Heavier fruit, such as peaches, necessitates much more aggressive pruning.

Almost all deciduous fruit trees should be pruned about now, before they bloom and foliate at the end of winter. Such pruning is too severe to be done while the trees are active in spring. Summer pruning to maximize production within less space is the only practical option to dormant pruning. Evergreen fruit trees, such as citrus and avocado, should not be pruned or groomed during winter.

The main group of deciduous fruit trees that require dormant pruning in winter are stone fruit, of the genus Prunus. This includes peach, nectarine, apricot, plum, prune, cherry, various hybrids and almond. The second main group are pomme fruit, such as apple, pear and quince. Fig, persimmon and grapevines, as well as roses, need specialized and perhaps very aggressive pruning too.

Dormant pruning of deciduous fruit trees, roses and grapevines is too complex to describe adequately here in just a few paragraphs. Nonetheless, those who grow such plants must be aware of how important it is, and ideally, know how to do it. Nowadays, it is nearly impossible to procure services of horticultural professionals who know or care how to execute such procedures properly.

They Don’t Know When To Quit

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The good news is that these billowy white blooms were not wasted.

The main difficulty with such a mild climate is that many plants do not get sufficient chill in winter. Several types of apples do not perform well here without it. Only a few are productive in Beverly Hills (in the Los Angeles region), where I sometimes need to modify my gardening column accordingly. A few of my neighbors here somehow grow peonies; but I do not even bother.

Even plant that require more chill than they get here seem to be aware that it is cooler at this time of year. Their deciduous foliage turns color and eventually falls to the ground. They just want the weather to get a bit cooler and to stay cooler for a bit longer before they are convinced that it is really winter. Otherwise, they think that autumn simply merges directly into spring.

I really do not know what hydrangeas are thinking though. They perform about as well in milder climates of Southern California, and may not bother to defoliate completely if old foliage can linger until it is replaced by new foliage. In the mildest climates, bloom is merely subdued through winter, but might continue sporadically. I am not convinced that they need any chill at all.

The hydrangeas here get pruned shortly after the roses, and almost as severely. (They are a bit more complicated than roses, and a bit less cooperative, but respond well to their pruning.) I started the process on Thursday with a few that needed to be relocated, and will be finishing on Wednesday or Thursday. Most of the remaining yellowed old foliage falls away in the process.

Their lingering bloom is a bit more disconcerting. I hate to waste what the old hydrangeas put so much effort into producing. Some of the best blooms were outfitted with a bit of eucalyptus foliage (since they lacked their own) and given away to others who work here. However, there were invariably some undeveloped blooms that were just discarded as they got pruned away.

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Undeveloped bloom was merely discarded with the rest of the debris.

Hydrangeas seem to appreciate a good chill, but do not seem to need it, or expect it to last for very long. I sometimes wonder if I could just groom them to remove old canes throughout the year rather than pruning them aggressively in winter. I do not remember ever pruning any in Southern California, but might expect them to be less responsive to the even milder weather.

For me, they would be easier to prune where winter is cool enough for them to be completely dormant. Without foliage, it would not seem like I would be pruning them while they are still active. Without bloom, I would not be concerned about the waste. I could just prune them like so many other deciduous plants. There really are a few disadvantages to mild winter weather.

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Hydrangeas that were transplanted got pruned and dug bare root.

Winter Is For Dormant Pruning

P90316++++The internet makes it possible to communicate with people who enjoy gardening all over the World. It can be amusing to hear what garden enthusiasts in Australia are doing now in early summer. Is it always summer in Ecuador? A common theme in much of America is that there is not much gardening to do right now. It might be more accurate to say that no one wants to go out in the cold.

Where winter weather is too unpleasantly cold to work in the garden, many winter chores can either be done earlier in late autumn, or delayed until early spring. Such scheduling is not a problem, since the plants involved are so deeply dormant through such cold weather anyway. Until the weather warms a bit, they do not want to work in their gardens either. Scheduling is very different here.

Not only does mild weather facilitate gardening chores, but it necessitates the completion of certain chores before the end of winter. Many plants that are mostly dormant while the weather is cool are actually dispersing their roots now that the soil is moistened by winter rain. They will be ready to break dormancy weeks before they would where winters are colder. There is no time for delay.

With a few exceptions, winter is the season for pruning here. Maples and birches should have been pruned earlier, or should be pruned later, so that they do not bleed sap. Citrus get pruned and groomed after the last frost because pruning stimulates new growth that is sensitive to frost. Early blooming flowering crabapples, flowering cherries and forsythias should get pruned after bloom.

Otherwise, most deciduous plants and many evergreen plants should be pruned in winter, while they are as dormant as they get. Pruning now will be less disruptive than it would be while they are more active. They wake up in spring and resume growth as if nothing happened, but relieved of the superfluous growth that was pruned away. Winter pruning is what fits best into their schedules.

Of all plants in the garden, deciduous fruit trees and roses rely on specialized pruning more than most others.

Work Day Renovation Of A Flowering Crabapple

P91020P91020+It is amazing what just a few parishioners and friends can accomplish in just a few hours from about nine to noon on Saturday morning. It is only happens a few times through the year, so we make the most of it to catch up on all sorts of maintenance and projects at Felton Presbyterian Church. (My parish should do this sort of thing.) I was there to work in the minimal landscape.

I started working with this ‘Prairie Fire’ flowering crabapple several years ago. As I pruned for clearance above the adjacent parking spaces and patio, I retained lower growth in the space in between. The tree bloomed too nicely to unnecessarily remove all that was right where it was most visible. Besides, from the patio, it was more visually appealing than a view of parked cars.

Then, I missed a work day. There were plenty of volunteers. There were plenty of power tools. There was plenty of enthusiasm. There was no horticultural expertise. Someone decided that my once exemplary flowering crabapple was in need of pruning, so executed the task with power hedge shears. The damage is irreparable. Lower growth is gone. Upper growth is mutilated.

It was very discouraging. It was done out of season, so I could do nothing to start to repair the damage at the time. There was not much left to repair anyway. I could only let the tree grow through a season so that there would be something to work with later.

Well, this was later. I would have preferred to wait for complete defoliation, but the tree is starting to go dormant now, which is technically good enough. I also would have preferred to prune less away; but really wanted to remove as much of the disfigured growth as possible.

I am less than pleased with the results. With all the disfigured lower growth removed, only the new upper canopy remains. The tree got what my colleagues might refer to as an ‘Ethiopia cut’, which is what much taller trees in Ethiopia get when their lower growth gets eaten by giraffes. It will be a long recovery.

The upper picture is the ‘before’ picture. The bright sunlight at noon does not look so good in the lower ‘after’ picture. I mentioned the Work Day and an update in my other blog, Felton League.

 

Workday

P90728Without prior notice, I was informed on Friday morning of a workday on Saturday morning at Felton Presbyterian Church. That was yesterday. Since there was no time to get other chores done in advance, I was an hour late. Considering that we only work for four hours between eight and noon, one hour is rather significant. I felt compelled to attend regardless. A few friends who are parishioners of Felton Presbyterian Church appreciate it.
The difficulty of not attending is that there are several other volunteers who do attend, and they all have very different ideas, or no idea at all, about how to accomplish what needs to be done in the landscape. It is amazing how much damage can be done with a few light duty power tools and too much undirected ambition. Even when I am there, it is difficult to convince the others that I know more about horticulture than all of them combined.
For the past several years, I had been pruning a flowering crabapple tree to renovate the branch structure that was mutilated by someone with loppers and power hedge shears. Yes, hedge shears. I had pruned the tree for clearance above a parking lot on one side, and a patio on the other, but with low branches in between to partly obscure the view of parked cars from the patio. Bloom was spectacular, and not compromised by the pruning.
Then I missed a workday. Even though the flowering crabapple tree did not need to be pruned at that time, someone lopped away the lower limbs indiscriminately, and then sheared the top! There were mutilated stubs all over the new exterior of the canopy. Much of the blooming stems for the following season were removed. It was very disappointing to see all of my effort wasted so pointlessly. Now, I need to start the whole process over.
However, when I got there today, a planter box below the crabapple tree was being dismantled and removed. I could not work in the area, so must return to start the process of renovating the crabapple tree. Realistically, it should be done while the tree is dormant in winter, even if it compromises bloom for the following spring somewhat. The tree is so gnarly and congested now that it is unlikely that anyone would notice a few less blossoms.
As frustrating as it can be, we actually get quite a bit done. These lily-of-the-Nile in the picture above were one of our projects many years ago. They were recycled from a garden in Aptos from which they needed to be removed. We split, groomed and plugged them. Most were promptly removed and discarded by someone else who did not realize that we had just installed them. But hey, at least these few survived and continue to bloom.

Sugaring Season

P90316KThere is no sugaring season here. Spring comes on too suddenly. By the time sap starts to flow, buds are already swelling.

Bigleaf maple, Acer macrophyllum, happens to be native here, although it is not common. It is the sugaring maple of the Pacific Northwest. A tree next to my driveway gave me enough sap to boil about four ounces of maple syrup a few years ago. That was all I needed to make the point to my colleagues who insisted that it could not be done that it really could be done.

Box elder, Acer negundo, is also native, and in riparian zones, is much more common than bigleaf maples is. I am told that is provides sap for sugaring just like any other maple does. Some say the sap is of inferior quality, or boils to cloudy syrup. Others say that it is comparable to that of any other maple.

Now that I made my point about getting a tiny bit of syrup from a bigleaf maple tree, I have no intention of sugaring again. However, sugaring season is still something that I need to be aware of. It is when I can not prune the maple trees. I can prune them earlier in winter or later in summer, but not while they are most vascularly active during sugaring season. Otherwise, they don’t stop bleeding. Even if the bleeding is harmless, it is unsightly if it stains the trunks and becomes infested with sooty mold as the weather warms.

The same rule applies to birch trees.

I pruned a few of the European white birch, Betula pendula, at work last week, believing that it was still too early for them to be too active. It was not much at all, and involved only a few small upper limbs and two significant lower limbs that had been disfigured by pruning for clearance from adjacent utility cables. I did not notice bleeding from the small stubbed limbs that I pruned from high in the canopy with a pole saw. Yet, the sap started to pour from the pruning wounds before I finished cutting away the two larger lower limbs that happened to be on the same tree. They are still bleeding now. In fact, they are bleeding so much that I feel badly that the tree is losing so much sap. If I had known how much sap would bleed, I could have put a bucket under each of the two wounds to catch the sap to make a small bit of syrup as is done in Alaska.

Attack Roses While They Sleep

8bd4This theme may be getting a bit redundant about now. There is just so much that needs to be done in the garden through winter for what will bloom in spring and summer. We plant new fruit trees, and prune mature ones. When we finish planting spring bulbs, we can start planting summer bulbs. Berries, rhubarb and grapes all get planted. With all this going on, it is also time to prune roses.

Like so many fruit trees through the past few centuries, modern roses were bred to maximize production. Instead of big and abundant fruit, they produce big and colorful flowers. Such enhanced production is more than overgrown rose plants can sustain. Pruning eliminates superfluous stems to concentrate resources into fewer but more vigorous stems, and flowers of superior quality.

Pruning also eliminates diseased, damaged, dead and dying stems; which are known as the ‘four Ds’. Foliage falls from the stems naturally through winter, but should be raked and disposed of because it can spread disease to new foliage in the spring. (Dormant fungal spores and bacteria overwinter in fallen foliage.) Foliage that clings to stems after pruning should be plucked away.

Pruning should ideally be done by the time buds begin to swell in late winter. Of course this is not as easy as it sounds in the mild local climate. Buds swell early, and may even start to grow before rose flowers from the previous season finish blooming! Modern ‘carpet’ roses and a few other shrubby types barely go dormant, but fortunately, they do not need such meticulous pruning anyway.

Hybrid tea roses need the most severe pruning, which leaves only three to seven canes approximately two feet high. These canes should ideally be unbranched below where they get pruned, and be spaced somewhat evenly around the center. Stout canes that grew last summer from the base of each plant are best. However, canes below graft unions are suckers that need to be removed.

Floribunda roses are pruned similarly, but can retain a few more canes. Some grandiflora roses are allowed to get significantly taller, with new canes on top of canes from the previous year, which may already be on top of canes from another previous year. It may take a while before they develop replacement canes from the base. Climbing roses likewise retain old canes for a few years.

Tree roses should be pruned as if the upper graft union is at ground level, so that canes should be about two feet high above the graft union. (Although, tree rose canes are usually pruned shorter.) Carpet roses and a few bramble types only need to be pruned low, but cane quality is not so important. They are not grafted, so can not develop suckers.

Winter Pruning Of Fruit Trees

90130thumbThe vast orchards of the Sacramento and San Joaquin Valleys might make the impression that production of fruit is easy. The trees naturally bloom in spring, and develop fruit over summer, as if they do most of the work prior to harvest. In reality, those trees have been so extensively bred to maximize production that they need, among other maintenance, very specialized pruning in winter.

Without pruning, deciduous fruit trees produce more fruit than they can support. The weight of the fruit breaks and disfigures limbs. Excessive fruit production exhausts resources so that, although more fruit is produced, it is of inferior quality. Diseases and insects proliferate in crowded stem growth that lacks vigor. Unharvested fruit that is beyond reach in upper growth may attract rodents.

Well pruned deciduous fruit tree produce fruit of much better quality, and are able to support it on well structured limbs that are reasonably within reach. They are less susceptible to diseases and insects. Such pruning seems severe to those who are unfamiliar with it, but it is necessary, and the trees appreciate it. Because it is so severe, it is done while trees are dormant through winter.

Different types of fruit trees need distinct types of pruning. Furthermore, different cultivars of each type may need different degrees of the same type of pruning. All should get the ‘four Ds’, which are ‘dead, dying, damaged and diseased’ growth, pruned out of them. Because figs produce early and late crops, they can be pruned less for more early figs, or more severely for more late figs.

Most of the deciduous fruit trees are either stone fruits or pomme fruits. The stone fruits include apricot, plum, prune, nectarine, peach and cherry, which are all of the genus of Prunus. Pomme fruits are apple, pear and quince. Because the winter pruning of deciduous fruit trees is so specialized and so intensive, it is worth studying, preferably before planting the fruit trees that require it.