Spring Pruning Of Flowering Trees

Some plants prefer pruning after bloom.

Most major pruning happens while the plants that need it are dormant through winter. That is why it is known as ‘dormant pruning’. Such pruning would be so much more disruptive while plants are blooming, fruiting, foliating or growing. Pruning that happens during other seasons is not as aggressive as dormant pruning. Spring pruning, although practical for some plants, is relatively docile.

For deciduous fruit trees, dormant pruning is very important. It concentrates resources into fruit production, but also limits production to sustainable quantities. Otherwise, such fruit trees would be unable to support the weight of their own copious fruit. Spring pruning of such trees is simply too late. By that time, superfluous fruit has already consumed significant resources, only to be wasted.

Stone fruit trees and pome fruit trees are familiar examples of deciduous fruit trees that rely on dormant pruning. Stone fruits include peach, nectarine, apricot, plum and their relatives. Pome fruits are primarily apple and pear. Ironically though, their fruitless but flowering counterparts perform best with spring pruning instead. As similar as they all are, they have completely different priorities.

Flowering cherry trees bloom more spectacularly than fruiting cherry trees, but produce no fruit. Similarly, flowering crabapple trees bloom more colorfully than fruiting apple trees, but produce only tiny fruit. Neither must sustain production of significant fruit. Nor must they support the increasing weight of developing fruit. Prolific bloom is their primary function. Spring pruning accommodates.

Spring pruning allows flowering trees to first bloom as profusely as possible. Pruned out stems have already served their purpose. Because fruit production is not a concern, spring pruning is less severe than dormant pruning. Nonetheless, because dormant pruning is so practical for so many plants, spring pruning may seem impractical. It is tempting to prune dormant flowering trees now. Doing so harmlessly compromises bloom.

Knowing When To Prune What

Flowering plum trees can be pruned later, after bloom.

Maybe the weather took the surprise out of camellias this year. It has been so warm and pleasant that such big and colorful flowers are almost expected. Even if crocuses and narcissus did not bloom much too early, they are likely finishing a bit early because of the warmth and minimal humidity. Daffodils are not far behind. Hopefully, lilies and tulips will not be too confused. Pansies, primroses, stock, Icelandpoppies, ornamental cabbages and kales actually seem to enjoy the odd weather.

It was such a rush to prune everything that needs to be pruned in winter! Roses are already being outfitted with new foliage. Plum trees are already blooming, and will be followed by apricots, cherries, peaches and the rest. It was actually easy to get carried away, and prune things that should not yet be pruned.

Many of the flowering trees that are related to fruiting trees seem like they should be pruned. However, the rules are different, since they do not need to support the weight of fruit. Pruning only compromises bloom. Flowering cherries, flowering (purple leaf) plums and shrubby flowering quinces should instead be pruned after bloom finishes, and only if necessary. As flowering crabapples finish bloom, minor pruning probably will be necessary.

Lilacs, forsythias and spireas should be pruned by ‘alternating canes’, which means that older canes get cut to the ground as they get replaced by new canes. If done just after bloom, new canes develop through the following summer, and will be ready to bloom the following spring.

Quite a few trees, shrubs and vines likewise want specialized treatment. Fat flower buds of deciduous magnolias make it obvious that pruning should be delayed. Azaleas should probably make their intentions to bloom more obvious. Hydrangeas can be groomed of deteriorated flowers and dead stems, but plump canes from last year will bloom this year. Maples, birches and elms will continue to bleed if pruned now, so should wait for summer.

Pruning Roses During Winter Dormancy

Pruning now promotes better bloom later.

Contrary to what the pleasant weather suggests, it is still winter. Most plants are resisting the temptation to break dormancy prematurely. They must know that the days are still short, regardless of the weather. Most plants are surprisingly proficient with scheduling. Nonetheless, dormant pruning should happen sooner than later. This includes pruning roses. They have been ready for a while.

Technically, roses are ready for pruning as soon as they begin to defoliate. Also technically, rose pruning can be as late as the buds of the bare stems remain dormant. Later pruning is preferable in some regions where pruning wounds are susceptible to pathogens. Such delay is riskier here where mild weather can disrupt dormancy prematurely. Wounds are less vulnerable to pathogens.

Pruning roses is about as important as pruning deciduous fruit trees. Without adequate pruning, rose plants become too overgrown to perform properly. Crowded stems are unable to elongate as they should. Diseases and insects proliferate in congested foliage, and damage bloom. Specialized pruning concentrates resources into fewer but significantly more vigorous stems and flowers.

Although the technique may seem to be drastic, pruning roses is not very complicated. Hybrid tea, grandiflora and floribunda roses should retain only three to six of their most vigorous canes. The canes should be only about two feet tall, and cut just above a healthy bud. If possible, they should be canes that grew during the previous year, from bottom to top. Older canes should be removed.

Pruning roses of other classifications may be slightly different. Some types may retain more canes. Climbing types likely retain old canes for several years before replacement. Carpet roses and other ungrafted roses can be cut nearly to the ground, leaving no canes at all. Tree roses are like bush types, but on top of short trunks. New canes grow from their graft unions on top of the trunks.

Of course, potentially vigorous sucker growth that develops from below the graft union of any grafted rose must go.

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.