A Strong Foundation

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Before: Camellias left the foundation exposed a long time ago, but instead obscured the view from the windows above.

‘Foundation planting’, which most of us think of as vegetation intended to merely obscure a foundation behind lower and prettier plants, has a simple utilitarian origin. Before homes were so commonly outfitted with rain gutters like they are now, densely shrubby foundation plantings diffused water that fell from eaves, and limited splattering of mud onto foundations and walls.

Nowadays, foundation planting only needs to look good, and maybe obscure crawlspace vents or exposed undersides of decks. They might be allowed to get as high as window sills, or higher.

These camellias got more than a bit too high. They had not obscured the cinder block foundation in a very long time, and did not contribute much to the shingled wall above. What was worse was that all of their best foliage and bloom obscured the view from the window above, and obstructed sunlight to the interior. They were impressive specimens, but were not doing their job.

We tried to prune their canopies lower and thinner, in order to promote more lower growth that we could prune down to later. They responded by merely replacing what was pruned away, exactly where it was pruned away from. We considered relocating the camellias to where such big and lanky camellia trees would be desirable, but they are too old and firmly rooted in place.

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After: Camellias can either start over or die.

The only option was to coppice them. It was quick and easy. We cut them to the ground with the expectation that they will either regenerate from their stumps or die. If they die, we will not miss them. (Okay, I might.) The new growth will obscure the foundation well, and after a few years, should resume blooming. They will be patchy if some but not all do survive, but we tried.

The remaining sculptural specimen obscures no windows.

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Stumps are a few inches high. Any new growth should hopefully develop on top, just above grade.

Silver Lining

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This little silver dollar tree did well with a second chance.

Among the more than seven hundred species of Eucalyptus, nomenclature gets confusing. It certainly does not help that some species have multiple common names. Eucalyptus cinerea is a rather distinctive species with at least two equally distinctive common names. The problem with these names is that, although sensible in Australian, they are not so sensible to Californians.

‘Mealy stringybark’ is a name that must describe something of the physical characteristics of the species. The bark is rather stringy, but no more stringy than that of so many other species. The glaucous foliage might be described as mealy in Australian English. ‘Argyle apple’ is a weirder name. Again, it must make sense in Australian culture. I just know it as ‘silver dollar tree’.

A few years ago, I acquired a severely disfigured and overgrown #5 (5 gallon) specimen of silver dollar tree, along with three comparable specimens of dwarf blue gum, Eucalyptus globulus ‘Compacta’. They were about to be discarded from the nursery where I found them. They got canned into #15 cans, and coppiced back to their distended lignotubers. All regenerated nicely.

Two of the blue gums found appropriate homes. One remains here, and was coppiced again last year. The silver dollar tree stayed late too, but happened to get planted into a landscape last autumn. It is developing into such an appealing tree that one would not guess that it had experienced such neglect and subsequent trauma. The exemplary silvery gray foliage is so healthy.

As it regenerated after getting coppiced, the strongest of the new stems was bound to a stake to form a single straight trunk. All smaller basal stems were pruned away after the first season. The little tree cooperated through the process, and now lives happily ever after. I still do not know its name.

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Silver dollar tree produces strikingly silvery foliage.

Dago Wisteria

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All this bloom will eventually be fruit.

My colleague down south and I have completely different gardening style. He is a renowned landscape designer, so his home garden is as elaborate as the landscapes he designs for his clients. I am primarily a farmer of horticultural commodities, so my home garden is very strictly utilitarian, with few items that are grown just because they are pretty.

My colleague’s garden is outfitted with a very well built pergola over the patio at the rear of the home. Six common Chinese wisteria were installed to climb the six supporting post and sprawl above. Their cascading spring bloom is both spectacular and alluringly fragrant.

Of course, when I saw that pergola while the wisteria were still young, I thought that it would be ideal for Dago wisteria, which most of us know simply as grapes. They climb like Chinese wisteria. They bloom with somewhat pendulous floral trusses that . . . sort of resemble wisteria bloom. Although they lack color and fragrance, they provide an abundance of fruit.

Now I get to work with some real Dago wisteria. It was planted years ago by someone who did not stay to maintain it. It got rather overgrown and gnarly before I pruned it into submission. Without a pergola, I extended vines from the rail fence that the main vines climb, over to a banister on the upper floor of an adjacent building. It works something like a pergola.

Because I do not know what cultivar of grape the vine is, I do not know what pruning technique it prefers. I happened to leave long canes last winter, just because they reached the banister on the opposite side so well. Now, the bloom is so profuse that I am concerned about the weight of the subsequent fruit pulling the rail fence over!

Multi Trunk Trees Seem Natural

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Overgrown shrubbery becomes multi trunk trees.

For several years in the late 1960 and early 1970s, European white birch were trendy. Most lived in ubiquitous groups of three. Where three did not fit, a single multi trunk tree, typically with three trunks, was a popular option. Each multi trunk tree provided as many trunks as a few single trunk trees. For these particular white birch, the elegant white trunks were their most appealing feature.

Multi trunk trees, which are popularly known as ‘multis’, are only structurally different from their counterparts with single trunks. Multi trunk crape myrtle are genetically identical to crape myrtle of the same cultivar, but with single trunks. The only difference is that multi trunk trees branch at ground level, instead of at the top of a single straight trunk. Each needs to be pruned to the desired form.

Multi trunk birch, paperbark and lemon gum exhibit appealing bark. More trunks display more bark than single trunks. Multi trunk strawberry tree, olive and oak exhibit appealingly sculptural form. Cork oak and crape myrtle provide both appealing bark and sculptural form. Silk tree, acacia and deciduous magnolia display their bloom more effectively with lower and broader multi trunk form.

Trees get help to develop into a desired form. European white birch, lemon gum and silk tree are more likely to develop single trunks naturally. Coppicing compels them to regenerate with several trunks. Conversely, olive, crape myrtle and strawberry tree develop a few trunks naturally. Single trunk trees need thinning to remove the superfluous trunks, and staking to straighten a single trunk.

In home gardens, multi trunk trees sometimes evolve from overgrown shrubbery. Pineapple guava may be shrubby for may years before lower growth gets pruned away to reveal sculptural trunks within. English laurel that gets too overgrown for containment pruning might become a delightful multi trunk tree instead. It will be pleased to grow freely from the top if lower growth gets pruned off.

Multi trunk trees are no more natural than trees with single trunks are, but they seem to be.

Horridculture – Jumpin’ Juniper!

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This is the backside of some of the better junipers!

Junipers have a bad reputation. They earned it at a time when they were too common. Too many were installed into situations that they were not appropriate for. As they grew, they were unpleasant to handle. If not handled enough, they became overgrown and shabby. Once that happened, there were nearly impossible to prune back into confinement without being ruined.

I was never one to completely subscribe to that bad reputation. There were just too many junipers that I really liked, particularly the Hollywood juniper and the Hetz blue juniper. There were a few that I disliked, and I still loath the common tam juniper, but they were in the minority, and happen to be the same sort that are becoming more scarce.

For landscape situations that they happen to conform to, there really is no reason for junipers to be any less appropriate than any other genus is. They are happy with local climates and soil types. Once established, they do not need much water at all, and many need no supplemental irrigation. They last for a very long time. Best of all, they need only minimal maintenance.

However, even some of the best junipers are not perfect. I know. I just needed to work with some that were installed in 1980, and, except for getting pruned back around the edges, were completely ignored. After days of trying to tame them, I can not longer deny that some of what I have not wanted to believe about them is very true.

Besides all the trash and road debris that had been dumped into them during the past four decades, they were thickly infested with Himalayan blackberry. Removing the bramble was not only wickedly unpleasant, but it exposed bare spots where juniper foliage had been shaded out. Removal of a few junipers that had been overwhelmed and died left even more bare spots.

Well, I could not just leave all the dead twiggy growth under the bars spots, so tried to remove some of that too. That only exposed more of what what under and behind it, and caused the well foliated stems above to sag into the whole mess. In the end, the junipers are an unsightly mess, and I know that they will stay that way for a very long time.

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Removal of all the bramble and dead junipers exposes a lot of bare branches.

No One Likes A Sucker

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Citrus have been bred for centuries.

Citrus trees that are grown from seed take a few years to mature enough to produce fruit. As they mature, the juvenile stems are outfitted with thorns that are even nastier than thorns on adult growth! Because most citrus has been extensively bred, seed grown trees are very likely to exhibit genetic variations. This is why citrus trees are cloned from stems of stock trees.

Cloned trees are genetically identical to their parents, so will always produce the same fruit. They are cloned from adult growth, so do not need time to mature from juvenile seedlings. They can therefore bloom and produce fruit as soon as their roots are ready. Also, their thorns are less dangerous.

Cloning citrus is not as simple as rooting them from cuttings though. With few exceptions, citrus trees are grafted onto genetically different rootstock. Most citrus trees in home gardens are grafted onto dwarfing rootstock that limits the size of the trees when mature. Orchard trees are grafted onto rootstock that allows them to get significantly larger.

The graft union, where the upper part of a grafted tree is attached to the rootstock, is typically visible just above the ground. The base of the trunk below the graft union is typically a bit more stout than the relatively lean section of trunk above the graft. Trunks of old trees are often more furrowed below the graft union than above it.

Sometimes, the rootstock tries to do more than provide roots. It can produce stems from below the graft union, known as ‘suckers’ that can potentially compete with the grafted portion of the tree above. Unfortunately, understock grows more aggressively than most types of citrus, so can overwhelm and shade out the desirable parts of an otherwise healthy citrus tree.

The most common understock for citrus produces suckers that are outfitted with unusually big and wicked thorns that are not to be messed with! If fruit develops, it seems to be humongous and disfigured lemons that lack flavor. Before they overtake good citrus trees, suckers should be pruned neatly away as they develop, without leaving any stubble to regenerate more sucker.

Horridculture – High & Mighty

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Camellias are pretty this time of year, but . . .

Camellias have been blooming for a while now. I typically get rather good pictures of them. The pictures are nothing too artistic, of course, and are intended to merely exhibit the floral color and form. A bit of the glossy foliage in the background is nice.

The picture above is not so useful for exhibiting much of the floral characteristics. Even the pink color is muted by the sloppy background and gray sky above. Zooming in would not have corrected the positioning of the flowers. I simply could not get close enough to do any better.

That eave in the lower right corner of the picture is above a two story building. That is where all the blooms of this particular camellia shrub are located. With so much of the lower growth shaded out and gone, this shrub is more like a small tree. The bloom is too high up to be appreciated. The picture below demonstrates what it all looks like without zooming in.

If there were windows facing this big camellia shrub or tree, I would likely prune it only a bit lower, just to keep it below the eave and within view of the windows. Without windows, I know that I really should prune the tall trunks back to what little lower growth remains, in order to promote more growth and bloom closer to ground level where it can be appreciated.

The difficulty I have with pruning it back is that this big camellia shrub or tree is so impressively big and sculptural, and all the glossy foliage looks so good in the foreground of the rich dark brown wall. I do not know what is more important here, the sculptural limbs and rich green foliage that lasts throughout the year, or the colorful but seasonal bloom.

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There is not much to see from this distance.

Frost Is Now Old News

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Minor frost can cause major damage.

Frost was something of a nonissue for some of us this winter. For those of us in milder climates, in rarely is. Those who limit selection of what grows in their gardens to species that are resilient to frost need not be concerned with it. Those of us who enjoy gardening a bit too much are more likely to grow a few marginal species that would prefer to be somewhere with milder winter weather.

Protection from frost might have been a concern prior to the onset of cold weather. Then, there was more concern for the few plants that might have been damaged by frost. Grooming and pruning of damaged foliage and stems needed to be delayed until after the threat of subsequent frost. Now that it is so late in the season, subsequent frost is very unlikely. It is safe to clean up any mess.

Pruning and grooming of foliage and stems that were damaged by frost is delayed for two main reasons. Firstly, the damaged material, although unsightly, helps insulate undamaged foliage and stems below it from subsequent frost. Secondly, premature removal of damaged material stimulates premature development of new foliage and stems that are more sensitive to subsequent frost.

Not only is it now safe to prune and groom frost damaged plants, but such procedures should not be delayed while affected plants recover. The same frost damaged material that provided a bit of protective insulation earlier would now interfere with the healthy development of new stems and foliage. Pruning can now promote new growth that was preferably delayed through colder weather.

Because the weather has been so pleasantly mild for quite a while already, new growth may already be developing among some frost damaged plants. Damaged material should be removed as carefully as possible to limit damage to such new growth. Many perennials that were not damaged this year might be pruned as if they were, to remove tired old growth, and promote new growth.

Many of the dormant spores of fungal and bacterial pathogens that overwinter in old foliage will be removed as such foliage gets groomed away.

Seasonal Pruning Is Precisely That

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Some trees get pruned after bloom.

Seasonal pruning is just as the terminology implies, seasonal. It might seem as if it all happens in winter. Most of it begins after cooling autumn weather initiates dormancy. Most of it is completed before warming spring weather stimulates vascular activity and resumption of growth. That is why most seasonal pruning is referred to simply as winter pruning. Winter really is best for most of it.

However, most is not all. Plants that are damaged by frost should not be pruned immediately. Because pruning removes insulating vegetation, and stimulates new growth that is more sensitive to frost, such pruning is delayed until after the threat of subsequent frost. Birches and perhaps maples are popularly pruned in late summer or autumn because they bleed so much if pruned in winter.

Flowering cherry, plum, peach, crabapple and quince do not need the same sort of pruning that their fruiting counterparts rely on. Their exquisite bloom is the priority, rather than fruit. Pruning prior to bloom could diminish their potential. They can instead be pruned immediately after bloom, as new growth is emerging, or later in summer after soft new growth has become a bit more resilient.

Lilac and forsythia should likewise be pruned after spring bloom, but more aggressively than the flowering fruitless ‘fruit’ trees. If not pruned enough, they will produce fewer canes through summer to bloom the following spring. Older and gnarlier canes should be cut to the ground to favor younger and less branched canes. Old Oregon grape and Heavenly bamboo canes can be culled too.

Redtwig dogwood and cultivars of willow that are pollarded or coppiced for their colorful twigs can be pruned later too. There is no need to deprive them of their primary assets prematurely. They should be pruned as winter ends though, before their buds start to pop. Pussy willow is an exception that gets harvested after buds have fuzzily popped, but before new growth begins to develop.

Evergreen plants can be pruned late in winter, just before new growth develops to replace what gets pruned away.

Deciduous Fruit Trees Need Pruning

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Dormant fruit trees will bloom soon.

Deciduous fruit trees have no business in a low maintenance landscape. They need as much specialized pruning while dormant in winter as roses need, and on a much larger scale. Neglected trees get disfigured by the weight of their own fruit. Disease proliferates in their thicket growth that develops without pruning. Overgrown trees produce most of their fruit where no one can easily reach it. Fruit that can not be harvested attracts rodents.

Of course, deciduous fruit trees are certainly worth growing if they get the specialized pruning that they need. Pruning concentrates resources so fewer but better fruits develop. Fruit bearing stems are better structured to support the weight of their fruit, and lower so that the fruit is easier to reach. Pruning also promotes more vigorous growth, which is less susceptible to disease and insects.

Now that it is February, and the weather has been unusually warm, deciduous fruit trees that have not yet been pruned will need to be pruned very soon. They will be sensitive to such major pruning once they start to bloom. The pruning is too specialized to explain here in just a few sentences. Fortunately, Sunset publishes an very detailed book about “Fruit Tree Pruning” that explains how to prune each of the different fruit trees. Pruning will be more extensive each year as trees grow, but also becomes more familiar.

Stone fruits like apricots, plums, prunes, nectarines and peaches (that have hard seeds known as stones), need the most severe pruning. Their fruit develops on stems that grew last year. These stems should get cut short enough to support the weight of the fruit expected to develop next year. The ‘four Ds’, which are dead, dying, damaged and diseased stems, should get pruned out as well. Cherries and almonds do not get pruned as much because their fruit is so lightweight; and out-of-reach almonds simply get shaken down anyway.

Apples and pears are pomme fruits that need similar pruning, but also produce on stunted ‘spur’ stems that should not be pruned away. Spurs may continue to be productive for many years. Figs, persimmons, pomegranates, mulberries and grapevines all need their own specialized styles of pruning.