Exceptions To The Pruning Rules

80228thumbWinter is the best time for major pruning of most plants. They do not mind it so much while they are dormant. However, there are exceptions. Winter pruning might be a bit too early for a few plants that are grown for their late winter or early spring bloom. It is best to wait until immediately after bloom to prune or trim flowering cherry, flowering plum, flowering crabapple and flowering quince.

Because these trees will be in the process of coming out of dormancy, it is best to prune them just after the blossoms finish, as new foliage is emerging. Some of the new buds will likely be ruined in the process, but there should be plenty to spare. If a few extra stems were left on deciduous fruit trees when they were pruned earlier, they can be taken as cut flowers prior to or while blooming.

Forsythia and Oregon grape should also be pruned after bloom, but with different technique. Oregon grape certainly does not need to be pruned annually, and may only need to be occasionally groomed of deteriorating stems. If and when it gets pruned, the oldest canes should be cut to the ground to favor newer canes. Forsythia canes should be cut to the ground after their second year.

Red twig dogwood and small willows that are grown for the color of their twigs must be pruned aggressively to produce new twigs for next winter; but there is no point in pruning their colorful twigs off while they are at their best. It is better to wait until just before new foliage is about to come out and obscure the twigs. They can be pollarded or coppiced. This applies to pussy willows as well.

Clumping grasses will start to grow soon, so can be shorn of their old foliage from last year that likely started to look rather tired by the end of winter. If left unshorn, new foliage and flower stalks will do just fine, but will come up through the old growth from last year, as the old growth lays down next to it and continue to decay. Once new growth develops, it will be more difficult to remove the old without damaging the new. Clumped grasses will look silly longer if shorn too early.

The Coast Is Clear

P80218Between here and Hawaii, there is a whole lot of water. Between Hawaii and Australia, there is a whole lot more. Everywhere to the west and southwest of California, there is a lot of water. Unfortunately, none of this huge volume of water is useful for gardening. It is saline. It would kill plants.

Of course this is not just any water. It is the Pacific Ocean. Although the water within it is useless directly, it is what feeds the weather that provides the precipitation that becomes the water that makes gardening and everything else possible. Rain fills local aquifers. Snow in the Sierra Nevada fills reservoirs as it melts.

The weather that the Pacific Ocean feeds gets shared over a very large area. Weather that does not make rain here might make rain or snow in Nevada, or Oklahoma, or really anywhere the weather wants to go to. In fact all the oceans all over the world cooperate to make climate and weather what it is.

What is so special about the Pacific Ocean being right here off the coast is that it moderates our climate and weather. Places like Nevada and Oklahoma that are not on the coast get water from the Pacific Ocean because weather is mobilized. The moderating effect of all that saline water is not. It stays right here in coastal regions.

Water has a high specific heat. That means that it takes a lot of energy to change the temperature of water. Saline water has an even higher specific heat. The temperature of the Pacific Ocean therefore changes very slowly and very minimally.

This inhibits extremes of temperature in the air above all that saline water. Small batches of extremely cold weather tends to collect a bit of heat energy as they pass over the Pacific Ocean. Weather coming in over so much saline water can not get extremely hot without the water absorbing at least some of all that heat energy. Therefore, coastal weather is rarely extremely cold or extremely hot. Temperatures can be more pronounced a few miles inland from the Pacific Ocean, especially when the weather comes from inland. Farther inland cold and heat can get significantly more extreme.

A lack of cold weather in winter limits what can be grown here. Plants that require a good chill are not satisfied with our pathetic winters. That is why some bulbs that do well as perennials farther inland bloom only once here, and why some varieties of apple that perform well in central Washington are not grown here.

However, a lack of hard frost allows us to grow many plants that can not be grown where winters are more severe. Even if bougainvillea gets frosted every few years or so, it typically recovers. Avocados and lemons are likewise quite happy here. The weather may seem to be boring, but it certainly has its advantages.

Little League

P80217+K1There are so many big trees in the Santa Cruz Mountains that keep most of us looking up. It is easy to miss much of the understory plants that grow on the forest floor.

While getting the pictures for the ‘Six on Saturday’ article posted earlier, I happened to notice these few small pale flowers that contrasted more with their own dark green foliage than they would have if they were more brightly colored. Perhaps that is a technique to get the attention of pollinators. It certainly got my attention.P80217+K2.JPGThe flowers were not completely white. They were very pale hues of pink. The wood sorrel in the last picture was slightly more pinkish than the unidentified cruciferous (of the family Cruciferae) flowers of the first two pictures. Pale flowers, particularly those that seem to be adorned with barely perceptible patterns, are typically those that use infrared and ultraviolet color to attract pollinators that can see such color. If that was their intention, they would not look so bland to the pollinators whom they prefer to attract.

Much of the surrounding dark green foliage is exotic (non-native) English ivy. It climbs some of the redwood trees and makes quite a mess of the forest. Native specie are too docile to compete with it. The two species in these pictures might have been more common years ago, before the English ivy invaded.

Neither of these specie are the sort that I would plant in my own garden. I do not even know what the first species is. The wood sorrel looks too much like related oxalis. Although several specie of oxalis are popular in home gardens, I still think of them as invasive weeds. Yet, in their natural environment, they are too happy and pretty to not be appealing.P80217+K3

Six on Saturday: Big League

 

Again, my six pictures are not from my own garden, which incidentally, is not at all interesting. Instead, these pictures are from the biggest site I work at. It is many acres, with some very big features.
1. Big lawns are acres of turf. The kid in front of the building in the distance shows how big the building and lawn is. This is the biggest of three big lawns.P80217
2. Big trees are very common here. These are coastal redwoods. There are also big Douglas firs and ponderosa pines.P80217+
3. Big water features are not constructed backyard fountains or koi ponds. This is Bean Creek, which flows into Zayante Creek less than half a mile away. It is more than a hundred feet below where the picture was taken.P80217++
4. Big shovels are necessary for working in such big gardens.P80217+++
5. Big garden sheds and big garden carts made by Dodge, Ford and Chevrolet are also very important.P80217++++
6. Big insects are quite at home in such big gardens.P80217+++++
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/

Daphne

70215When the weather warms up a bit between frosty weather and winter storms, the rich fragrance of winter blooming daphne, Daphne odora, is at its best. The domed trusses of tiny pale pink flowers are not much wider than a quarter, so are easy to overlook while investigating the source of the fragrance. ‘Aureomarginata’, the standard cultivar, has glossy evergreen leaves with narrow pale yellow margins. Mature plants are only one or two feet high. All parts of the plant are incidentally toxic.

It is no mystery why daphne is rare. It can be rather finicky, and unpredictably so. It purportedly wants rich and slightly acidic soil, in a warm but partially shaded spot; but can be difficult to grow even in ideal conditions. Yet, it is sometimes seen doing well in full sun or in dense soil of questionable quality. To make matters worse, even the healthiest plants live only about five to eight years.

Year of the DOG!

P71019

Tet, Vietnamese New Year’s Day, is today! This is the first day of the Year of the Dog! Tet is celebrated for at least three days, and besides all the popularly known traditions that go along with it, a few horticulturally oriented traditions are also observed.

When I grew citrus back in the early 1990s, I can remember than we sold every kumquat and calamondin tree that had fruit on it prior to Tet. When those ran out, we sold every fruited mandarin orange and tangerine tree, and then every fruited orange and lemon tree. Eventually, just about every fruited tree we could supply was gone. Citrus trees with colorful ripe fruit are traditional decoration for Tet, and might even be a gift for someone lacking such a tree. Kumquat trees are the favorite, but others will do if necessary.

Fruit baskets containing primarily citrus fruits are also very popular and traditional. Bananas, pineapple and any colorful fruit are fair game as well. Shaddock fruit is popular if available. Shaddock is the dwarfing understock for other dwarf citrus trees, but is not commonly grown for fruit production.

Blooming stems of apricot, peach and plum, as well as Saint John’s wort flowers, are the favorite traditional cut flowers for Tet. Each type of flower corresponds to the region of Vietnam from which the family displaying it originated. In the Santa Clara Valley years ago, there were plenty of fruit blossoms to go around. The stems were sometimes cut early and forced to bloom on time for Tet. Nowadays, such blooming stems can be purchased from florists, along with the other traditional flowers; chrysanthemums, narcissus, marigolds, pansies and cockscombs. Families who own a bonsai or more display them prominently for Tet.

Happy Tet and Year of the Dog!80131

Perennials Can Divide And Conquer

10810Along with all the bare root fruit trees, roses and cane berries, nurseries also stock bare root perennials like strawberries, asparagus, horseradish and rhubarb. They are so easy to plant while dormant. They recover from transplant through spring, and by summer, should be growing as if they had always been there. Although, if they had always been there, they might be crowded by now.

Yes, many but not all perennials eventually get crowded. Strawberries spread by runners, so are easily plucked and transplanted to avoid overcrowding, as well as to propagate more productive plants. Asparagus are variable, so may not get crowded for decades. Horseradish and rhubarb may not mind getting crowded, but could be more productive if individual plants have their space.

For example, crowded horseradish plants produce many small roots. If dug, split apart, and replanted with more space between individual plants, the individual roots get much larger. Separating the roots, which is known as ‘division’, also produces many more new plants. Mature rhubarb plants may not mind being crowded, but are often divided simply to propagate new productive plants.

Division of these sorts of perennials is typically done while they are dormant through winter. If that sounds familiar, it because it is the same reason why these sorts of perennials are available as bare root stock. They get processed while they are unaware of what is happening, and wake up in their new and better situations. Many defoliate while dormant. However, most are evergreen.

Ornamental perennials like lily-of-the-Nile, African iris, New Zealand flax, society garlic, torch lily, lily turf and acorus grass are all good candidates for division if and when they become overgrown. So are most aloes, some terrestrial yuccas, several ferns and some of the more resilient clumping grasses. Agave pups can be dangerous, but really should not be allowed to get too crowded.

Division might be as simple as taking a few pups or sideshoots from a large clumping plant, or as involved as digging an entire large plant to divide each individual shoot. More often, large plants get dug and split into a few smaller clumps of many shoots. New plants should be groomed of deteriorating foliage. The long leaves of New Zealand flax should be cut in half to avoid desiccation.

More Misplaced ‘Environmentalism’

P80214Nature has been getting by just fine for a very long time before humans started to interfere. It has survived all sorts of catastrophes literally longer than anyone can remember. It was here when dinosaurs were exterminated by a meteorite or comet or vulcanism or whatever catastrophic yet natural event finished them off. In fact, Nature was here for all of the few mass extinction events of the very distant past, including the Permian – Triassic Extinction, which only about 4% of life on earth survived! We all know that “It’s not nice to fool with Mother Nature.”, or serve her margarine that tastes like real butter; but we should also realize that it is rather presumptuous to think that we can be more efficient with correcting all environmental damage. Very often, it is best to let nature do what nature does best.

For example, forest fires are perfectly natural. They are more frequent now because of human activity; but they are less extensive, likewise because of human activity. Humans contain fires that would naturally burn much larger areas. Preventing vegetation from burning allows it to accumulate and become more combustible. If deprived of fire long enough, vegetation within ecosystems that rely on fire as part of their natural restorative cycle eventually deteriorates, or become so combustible that when it does burn, its seed gets incinerated.

Many box elders along the San Lorenzo River have been dying for the past many years. We have not identified the pathogen associated with the necrosis, but it is probably a naturally occurring pathogen that is an intricate component to the natural ecosystem, (although after last winter, an inordinate number of box elders succumbed at the same time). Regardless, trees succumbed and fell. A significant void developed within the collective forest canopy on the Eastern Bank, near the Graham Hill Road Bridge. ‘Environmentalists’ wanted to ‘help’.

These new trees in the picture were planted within the area vacated by a few deceased box elders. The closer of the two is a coast live oak. The other is a bay laurel. There are a few more beyond those in the picture. Native vegetation that developed ‘naturally’ but happened to be in the way was removed to facilitate this project. To prevent native deer from damaging the trees as deer would do ‘naturally’ the trees were imprisoned in small cylindrical cages. Because the trees did not grow there and disperse their roots ‘naturally’, they must be irrigated until they can survive on what they get ‘naturally’ from rain.

The irony of all this is that native vegetation that was growing ‘naturally’ was removed to install ‘unnatural’ nursery grown trees intended to restore a ‘natural’ ecosystem that was already doing what it does ‘naturally’. Although native, the coast live oak ‘naturally’ prefers to avoid riparian environments such as this. It ‘naturally’ prefers a more exposed and drier situation. Bay laurel trees live there ‘naturally’, which is why a few had already started to grow from seed. These seedlings would not have needed to be caged or watered, but were removed to plant the new trees. Yes, bay laurels that would have survived on their own were replaced by bay laurels that must be watered and protected. Willows and cottonwoods that were quite prolific in the area were likewise removed, although many more remain lower on the bank of the River.

In the background, in the upper right corner of the picture, the bright yellow flowers of an Acacia dealbata can be seen. It is a seriously invasive exotic species that displaces native vegetation. Although it is impossible to exterminate the species, this individual tree that has been dispersing profuse seed into the San Lorenzo River for many years, really should be removed. Even if nothing were to be installed to replace it, the removal would benefit the ecosystem. Nature would have no problem finding native trees that would like to occupy that spot.

Snowdrops

80221Where winters are more wintry, garden enthusiasts get to brag about their snowdrops as they emerge and bloom through melting snow. Diminutive white flowers against a backdrop of white snow may not look like much to us. We have more colorful flowers through winter, without the snow. Their kind of snowdrops, Galanthus specie, need more winter chill than they would get here anyway.

We have our own kind of snowdrops though. Leucojum aestivum does so well without significant winter chill that it can naturalize, and sometimes shows up in well watered gardens and riparian areas without being planted intentionally. Leucojum vernum is similar, but blooms with only single or paired flowers, rather than three or more small and pendulous flowers on each arching stem.

The rubbery leaves are about half an inch wide and a foot tall. They stand rather vertically, and can get nearly twice as tall if they need to grow through groundcover. The flower stalks are about the same height, and with the weight of the drooping flowers, might lean a bit outward from the foliage. Each flower has six white tepals with a yellowy green spot near the tip. All plant parts are toxic.

Pollarding And Coppicing Pruning Techniques

80221thumbJust about any other arborist will say that pollarding and coppicing are wrong. These techniques ruin trees so that they can never develop into their natural form. Although restorative pruning after pollarding or coppicing is possible, it is usually more trouble than it is worth. However, no one can deny that properly pollarded and coppiced trees can live much longer than they would naturally.

Pollarding and coppicing are extreme pruning. Coppicing is literally cutting a tree down to a stump just above the ground. Pollarding is almost as severe, but allows the main trunk and main limbs to remain. It does not end there of course. It must be repeated annually to maintain the coppiced stump or pollarded trunk and limbs. Secondary growth gets pruned off, back to the previous cuts.

After this process is repeated for a few years, coppiced stumps and pollarded limbs develop distended ‘knuckles’. Cutting back to but not below these knuckles facilitates compartmentalization (healing) of pruning wounds. Because the secondary growth is only a year old when cut annually, the wounds are relatively small, so they get grown over by new growth during the following season.

English style pollarding leaves one or two stubs of any desired length on each knuckle annually. These stubs are generally but not necessarily selected from stems that are aimed upward and outward. This technique elongates knuckles so that the trees are more gnarly and sculptural. Otherwise, all other stems must be pruned away cleanly. Stubs interfere with compartmentalization.

Pollarding and coppicing are done while trees are dormant in winter, and only to the few specie of trees that are conducive to it. These techniques were historically used to generate firewood, wiry willow stems for weaving baskets, straight fence stakes, or lush foliage for livestock and silkworms. Nowadays, they are done to keep big trees small, enhance the size and color of leaves, enhance the color of bark (on twiggy secondary growth), maintain juvenile foliage, or to prevent the bloom of allergenic flowers.