Mugo Pine

60608‘Shrubbery’ sounds so unflattering for a pine; but mugo pine, Pinus mugo, is not really much of a tree. The tallest trees do not reach eaves. Most old trees are only a few feet tall and about twice as broad, with strictly rounded form, and dense forest green foliage. The stout paired needles are only about one or two inches long. The plump cones, which are rarely seen, are not much longer.

Although very rare in other types of landscapes, and originally from the Austrian and Italian Alps, mugo pine is one of the most popular and traditional features in Japanese gardens. Even though it grows very slowly, it should have enough room to do so without competing with other more aggressive plants that might overwhelm it. It should neither be shorn nor pruned back too aggressively.

The Wrong Time For Pruning

80801thumbNot many plants are sensitive to mere heat alone. Actually, many plants prefer warm weather. The difficulty that some plants have with heat locally is that it typically accompanies aridity, and often accompanies afternoon breezes. As appealing as breezes and minimal humidity are to us while the weather is warm, they promote and accelerate desiccation of exposed sensitive foliage.

Pruning, which obviously becomes necessary while warm weather promotes growth, can make plants more sensitive to damage caused by warm, sunny, arid and perhaps breezy weather. It exposes formerly sheltered stems and inner foliage, which are more sensitive than outer foliage is, to more sunlight and drying breezes. Exposed foliage can either desiccate or roast, or both!

A bit of unsightly but relatively minor foliar damage on the extremities of the outer canopy might be only superficial, but major damage can be dangerous. Superficial damage often gets replaced by fresh new growth before it deteriorates enough to expose more foliage and stems below. However, recovery from major damage can be delayed by the distress associated with the damage.

Japanese maple, aralia, philodendron, rhododendron and all sorts of ferns can easily get damaged by increased exposure. Low ferns are not likely to become too exposed by any loss of their own foliage, but often become more exposed by the pruning of plants above them. Like frost damage, foliar scorch might need to be left to shelter remaining foliage until new growth develops.

The bark of many plants, although not susceptible to desiccation, is very sensitive to sun-scald if too exposed. Young and smooth bark is the most sensitive, particularly if it had always been shaded. Scald kills bark and the vascular tissue below. As it decays, it exposes interior wood to more decay that is likely to compromise the structural integrity of the affected stems and trunks.

Pruning during relatively cool weather and while there are a few relatively cool days in the forecast allows foliage a bit of time to adapt to a new exposure before the weather gets dangerous. Through summer, pruning should not be so aggressive that too much sensitive foliage or bark are exposed, even if it is necessary to leave a bit of unwanted sloppy growth to partly shade bark. Aggressive pruning of exposed and sensitive plants should be delayed until autumn, when sunlight is not so intense, and weather is cooler and wetter.

Horridculture – Fruity Fads

90417Pluots, plumcots, apriums and peacharines! Who comes up with this stuff?! Aren’t good old fashioned plums, apricots, peaches and nectarines good enough? Who decides that these weird hybrids are somehow better than their parents? Some of them are actually quite weird, or downright ugly. Several do not even look like they would taste good. It may be an acquired taste; but I have all the good taste that I need without acquiring any more.
Some old classic cultivars (cultivated varieties) of fruit were develop centuries ago. More have been evolving from those ancestors since then. Some were intentionally bred from parents with desirable qualities. Others just grew incidentally where their seed fell, and were found to be somehow better than their parents. Some were merely discovered as natural occurring mutants, and perpetuated for their superior qualities. It is a slow process.
So, putting two different kinds of fruits together, or finding an aberration of a single type of fruit, is nothing new. Tangelos were created by hybridizing Mandarin oranges with pomelos or grapefruits. Ever-bearing ‘Eureka’ lemon was perpetuated from a mutant of the seasonally bearing ‘Lisbon’ lemon. This is how cultivars evolve and develop. Generally, newer cultivars become popular because they are somehow superior to their ancestors.
Yes, somehow ‘superior’ to their ancestors. Who decided that a hideous hybrid of a plum and an apricot was somehow better than either a perfectly good plum or apricot? Furthermore, what evidence was there for such a weird claim? Even farthermore (if that is a word) how and why do so many people believe this evidence?
I was still growing citrus (trees not fruit) back in the early 1990s when the ‘Cara Cara’ pink orange was popularized. Yeah, a ‘pink’ ‘orange’. It is really just a pink mutant of the formerly more popular ‘Washington’ navel orange. We could not grow enough of it. It was just too popular. Some people really seem to believe that it is somehow better than ‘Washington’ and other navel oranges. I can’t argue. They certainly know what they like.
To me, it has a milder flavor than ‘Washington’. Yes, it tastes about as bland as it looks; pink.90320thumb

Shasta Daisy

90612It just might be one of the most popular daisies nowadays, but Shasta daisy, Leucanthemum X superbum, is not a naturally occurring species. It was developed by Luther Burbank in 1890, as a complicated hybrid of four different species, one of which is of a different genus. Yet, it is somehow genetically stable enough to produce viable seed, although seed of cultivars is not true-to-type.

Shasta daisy is an herbaceous perennial that forms a substantial network of sturdy rhizomes that mostly stay close to the ground, with blooming stems that can get almost three feet tall. Primary bloom begins in late spring or early summer, and continues until autumn, either in minor subsequent phases or as sporadic bloom. Flowers are big classic white daisies with bright yellow centers.

Although it can survive neglect and lapses of watering, Shasta daisy prefers to be watered at least occasionally, and is much more appealing if flower stalks are pruned away as they finish. It likes full sun, but will tolerate a bit of shade through part of the day. Mature plants are easy to divide for propagation. If the odd aroma is not too objectionable, Shasta daisies are delightful cut flowers.

Deadheading Promotes And Prolongs Bloom

90612thumbApril showers bring May flowers. May flowers make a mess. Well, some of them do. Most simply disintegrate and fall from the trees, shrubs and vines that produced them, and decompose into the soil below. Some might have needed to be swept off of pavement and decks. Regardless, most of us do not notice the very minor consequences for the majority of spectacular spring bloom.

However, there are some flowers that demand a bit more attention after they finish blooming. They linger after the show is over, and can look shabby as they deteriorate. Small ones can simply be plucked. Larger blooms might need to be pruned out. The process of removing deteriorating blooms is known as ‘deadheading’, and it is done for more reasons than just to keep plants groomed.

Plants bloom to produce seed, and the production of seed takes resources. Removal of seed structures not only diverts resources to more useful functions, but for many plants, it also stimulates subsequent bloom in response to interrupted seed production. They literally keep trying until they are able to produce viable seed, even if they must continue all season until late autumn dormancy.

Most plants that benefit from deadheading are perennials. Shasta daisy, black-eyed Susan, blanket flower, cone flower, yarrow, lavender and beard tongue (penstemon) bloom more abundantly and for a longer time with regular deadheading. The various lavenders, as well as other perennials that are comparably shrubby, are easily deadheaded by shearing after profuse bloom phases.

For bulbs and bulb like perennials that bloom only once annually, deadheading will not promote subsequent bloom during the same year, but conserves resources for the following year. Daffodil, lily, clivia, various iris and, during summer, gladiolus and dahlia, all appreciate diligent deadheading.

Petunia and marigold are two annuals that happen to bloom better with regularly deadheading. They bloom so profusely that deadheading can be quite a chore. Plants that can be invasive, such as salsify, should be deadheaded before dispersing seed.

Aw NUTS!

P90602Not just any nuts, but precisely the sort that I recently discussed with a colleague, as I explained how they do not grow here. The nuts that is. The big thicket forming shrubs that are supposed to produce them not only grow here, but are a relatively common native. I just rarely see even a single nut on them. I sort of wondered how they mange to procreate with such rare seeds that invariably get taken by unconcerned rodents or birds.
They are the beaked hazelnut, Corylus cornuta. You can see why they are known as such. The elongated nut husks look like Big Bird. The very rare nuts within are quite small with good rich flavor, like hazelnut concentrate, and develop only on the biggest and most distressed old hazelnut shrubs.
However, the young and healthy hazelnut shrub that produced the nut in this picture actually produced quite a few. They were just not close enough to each other for me to get more than one in a picture. A few other young and healthy hazelnut shrubs are doing the same at the same time. There are more hazelnuts now than I have seen collectively in many years. I can not explain why.
Some species of oak tend to produce an overwhelming abundance of acorns every several years or so, only to limit acorn production for the several years in between such abundance. All trees of the same species within a region somehow know to do this collectively at the same time. They do not do it often, but when they do, they do it together.
The oaks who do this supposedly produce just enough acorn to sustain a healthy squirrel population without promoting overpopulation. When they occasionally produce an excess of acorns, the squirrels instinctively bury many more acorns than they normally would, just because the acorns happen to be available. Since the squirrels can not consume all that they bury, many more stay buried to germinate and grow into trees later.

Rose Lily

P90601KWhat a delightful surprise! It happens sometimes here in the rose garden. It may not look like much, as a short stemmed single lily floret that is mostly overwhelmed by the English lavender that I held back with my boot for this picture. It should be three feet tall or so, with several florets. The surprise is that no one planted it. Well, at least no one planted it recently. This rose garden has more history than is obvious from what blooms here now.
Old pictures show that it was formerly an extravagant perennial bed, with an abundance of canna, dahlia, penstemon, pelargonium, Shasta daisy, Japanese anemone, various iris, and of course, various lilies. Lower annuals were cycled through the seasons at the front edge. Only a few roses bloomed against the low wall at the rear. Soil was likely regularly amended with compost and fertilizer. Someone put significant effort into maintaining it.
Nearby redwoods appreciated all the effort, and extended their roots into the fertilized, richly amended and regularly irrigated soil. Their growing canopies extended over and shaded the upper portion of the perennial bed so that all but daylilies and Japanese anemone were replaced with ferns. Perennials that got dug and stored for their dormant seasons were later installed elsewhere as it became obvious that they would not be happy here.
Because the few roses did not seem to mind the redwood roots, a few more, as well as English lavender, were added in informal rows to replace deteriorating perennials. Annuals require more effort than they did originally, but are still cycled through the seasons in a narrow row at the front edge. The rose garden now seems to have always been here, as if intentionally planned. Every once in a while, we find reminders of extravagant history.

Six on Saturday: Oh, The Shame!

 

Not my shame of course; but that of the trees in the pictures below.

Do not try this at home. I only did it because I am a horticulturist and arborist; and I happen to be one of the last arborists in America who condones coppicing and pollarding, which are depicted here.

Coppicing is cutting trees or shrubbery down to the ground annually, or at least regularly every few years or so. Some coppiced trees form basal burls or lignotubers. Some just form thicket growth that replaces itself after getting coppiced back to the ground.

Pollarding is similar to coppicing, but rather than cutting all growth back to a stump or stumps at ground level, it involves pruning all growth back to the same distended knuckles at the ends of a few main limbs annually, or at least regularly every few years or so. It is done in such a manner that the pruning wounds are compartmentalized by the new growth of the following year. Knuckles can be elongated by leaving single short stubs.

There are a few reasons for coppicing and pollarding. Some subjects develop an abundance of appealingly lush foliage. Some develop an abundance of appealing or useful twiggy growth. Coppiced red twig dogwoods are much twiggier and more colorful while bare in winter. Pollarded or coppiced willows produce an abundance of canes for basketry. White mulberries are pollarded to provide an abundance of lush foliage to feed silkworms.

I coppiced a Eucalyptus globulus ‘Compacta’ and pollarded a Eucalyptus globulus for two main reasons. Both are such problematic trees that I do not want to plant either into the ground, so must keep them contained. Also, I want the remarkably aromatic juvenile foliage that develops in response to coppicing and pollarding.

1. Eucalyptus globulus ‘Compacta’ coppiced stump. It is not such a great example of a coppiced stump, since the tree did not grow enough two years ago to get coppiced last year. Consequently, the few main trunks that were just recently coppiced are already starting to form their own separate lignotubers on top of the original, which is now rotting below. Soon enough, they will fuse to form a single lignotuber, concealing the evidence.P90601

2. Eucalyptus globulus ‘Compacta’ before getting coppiced. It is quite small for a specimen that was not coppiced last year.P90601+

3. Eucalyptus globulus ‘Compacta’ after getting coppiced. Rhody is not impressed.P90601++

4. Eucalyptus cinerea in need of pollarding. This tree grew too big too fast to survive any longer in the relatively small #15 (15 gallon) can. Fortunately, in just a few days, it will instead get installed into a landscape where it can disperse roots and mature into a normal unpollarded tree. After a few years, it might get pollarded anyway, just to produce silvery juvenile foliage withing reach of the ground, but that is not a concern just yet.P90601+++

5. Eucalyptus globulus pollarded knuckle. This is only the second pollarding procedure for this subject. The first procedure involved lopping the lanky single trunk off right here where the knuckle is now. The multiple limbs that developed were just recently lopped off, leaving this distended knuckle to repeat the process, hopefully annually.P90601++++

6. Eucalyptus globulus pollarded trunk. This is why Eucalyptus globulus should not get pollarded! They look ridiculous if deprived of their naturally elegant form. They do not look much more dignified with multiple pollarded limbs. Oh, the shame!P90601+++++

This is the link for Six on Saturday, for anyone else who would like to participate:

https://thepropagatorblog.wordpress.com/2017/09/18/six-on-saturday-a-participant-guide/

Holly Fern

60601This is one of those perennials that has mixed reviews. Although relatively tough once established, holly fern, Cyrtomium falcatum, is susceptible to rot and fungal leaf-spot. It likes to be watered somewhat regularly, but rots if the soil is constantly saturated. Leaf-spot is not as dangerous as it looks, but can be unsightly. Too much fertilizer (to correct the damage) can burn the foliage too.

Individual fronds might get as long as a foot and a half, with half a dozen to a dozen pairs glossy and irregularly toothed pinnae. Foliar texture (remotely) resemble that of some types of holly. Because they disperse their roots so efficiently, mature specimens do not like to be transplanted. Small plants can grow as houseplants for years, but eventually want to get out into the garden. Holly fern likes a bit of shade, and will tolerate rather dark shade.

Ferns Are Shady But Cool

P90309+++++It could be either an asset or a liability. With few exceptions, ferns do not want to be too exposed to direct sunlight or wind, especially during warm and dry weather. However, as long as they get just enough filtered light, they can be quite happy in sheltered spots that are a bit too shady for other plants. Most like to be watered regularly, and perhaps lightly fertilized in spring and summer.

They provide neither floral color nor fragrance. They lack interesting branch structure and bark. Since they reproduce by spores, they do not even produce any fruit, either edible or ornamental. For those who do not know them any better, they might seem to be rather boring. Yet, those of us who grow them know how handsome their lush, finely textured and uniquely patterned foliage is.

Of the popularly grown ferns, only two develop ‘trunks’, (which are actually just clustered wiry roots growing downward through rotting stems). Two others are ‘epiphytes’ that naturally cling to trees or exposed stone, but in home gardens, are more popularly grown on wooden plaques. Most other ferns are terrestrial understory perennials that naturally live in the partial shade of larger plants.

Although mostly confined to the ground, some ferns can get quite large. Individual leaves, which are known as ‘fronds’, can get several feet long. Even before it develops a trunk, Australian tree fern produces huge fronds that can shade an atrium. Other ferns with smaller leaves can spread very efficiently, and can even become invasive. Fortunately, most ferns are relatively complaisant.

The two popular epiphytic stag-horn ferns have weirdly lobed but otherwise undivided fronds. Leaves of the odd bird’s-nest fern is neither divided nor lobed. Otherwise, fern fronds are intricately divided into small leaflets known as ‘pinnae’. These pinnae are neatly arranged on opposite sides of leafstalks known as ‘rachi’. Some ferns have silvery variegation, but most are rich dark green.

Ferns innately do well in pots. Boston, maidenhair, rabbit’s foot, holly and bird’s-nest ferns are actually excellent houseplants. However, Australian tree fern and a few others shed irritating fuzz that would be a problem in the home. Most of the popular ferns are evergreen. Many consume their own deteriorating foliage by covering it with new foliage. Some ferns need occasional grooming.