Frost Damage Makes Its Appearance

Frost damage of canna looks shabby.

Exotic plants are not native. They are from someplace else. Yet, most plants within most home gardens are exotic. Most are capable of tolerating the more extreme climates from which they originated. Some tropical or subtropical plants actually prefer milder climates. After the recent cool weather, some vulnerable plants exhibit symptoms of frost damage.

Vulnerability is relative though. Honeybush and elderberry can be mostly evergreen with minimal chill, or deciduous with more pronounced chill. Both tolerate more chill than they can experience here. What may seem to be frost damage of specimens that are normally evergreen could be a normal deciduous response to slightly abnormally cooler weather.

Frost damage is also relative. Partial defoliation of Mexican lime might happen annually after minor frost, so may not be alarming. However, such seemingly minor damage could involve stems or entire trees. Luxuriant canna foliage that so instantly becomes unsightly after minor frost can be more alarming. However, dormant rhizomes are safe until spring.

The simplest means to avoid frost damage is to not grow plants that are susceptible to it. Obviously, that is quite limiting. Besides, plants that were not susceptible last winter may be susceptible this winter or sometime in the future. Weather is annually variable. Some susceptible plants can grow in pots that are portable enough to relocate to winter shelter.

Small but immobile plants that are vulnerable to frost damage may appreciate temporary shelter during frosty weather. Any sort of sheeting or cardboard suspended by any sort of stakes and strings should be adequate. Ideally, the sheeting should not touch the foliage below. Incandescent Christmas lights under such sheeting radiate a slight bit of warmth. Frost occurs only at nighttime locally.

Frost protection can be unsightly, but it is less unsightly than frost damage. Fortunately, it is temporary during frost. If not too unsightly, most frost damage should remain until after the last frost date. It insulates other vulnerable vegetation within. Furthermore, premature grooming or pruning stimulates new growth that is more vulnerable to subsequent frosts.

Grafting fact and fiction

The scion is above this graft union. The rootstock is below.

There are not many Californians of my generation who do not remember growing avocado trees from seeds when we were kids. We simply impaled the big seeds around the middle with three evenly spaced toothpicks to suspend them from the rims of Dixie cups partly full of water. If just the bottoms of these seeds remained properly submerged, they grew roots and a stem with a few leaves, all they needed to grow into trees that were producing too many avocados by the time we got to high school.

Yet, I and others of my generation have always heard that avocado trees need to be grafted to produce fruit. (Grafting is the union of two or more compatible but different plants. The ‘scion’ is the upper portion that forms a trunk, branches and foliage. The ‘rootstock’ is the lower portion that provides roots.) Well, this is obviously not true, but does make us wonder about the advantages of grafted trees.

They myth of seed grown trees being unproductive probably originates from the tendency for seed grown avocado trees to be unproductive for the first few years during the juvenile stage. Scions of grafted trees are taken from adult growth that is ready to bloom and fruit immediately; although even grafted trees need a few years to grow large enough to produce more than just a few avocados.

Many plants are juvenile while young, in order to better compete in the wild. While juvenile, avocado tree seedlings grow vigorously enough to compete with other trees. Adult habits of blooming and fruiting would only slow them down. Besides being fruitless for many years, citrus seedlings are very thorny through their juvenile phase, to avoid getting eaten by grazing animals. Scions of grafted citrus trees are from relatively thornless adult growth that is immediately ready to produce fruit.

The primary advantage of grafting fruit trees though, is keeping the many different cultivars (cultivated varieties) ‘true to type’, since many seed grown plants exhibit at least some degree of genetic variation from their parents. For example, avocados from seed grown (ungrafted) trees tend to be much larger, but often less flavorful than the fruit that the original seed came from. No one really knows what the fruit will be like until it actually develops. Some seed grown peaches are indistinguishable from their parents, but most are very different. However, most pecans and chestnuts are actually produced from ungrafted seed grown trees.

The secondary advantage of grafting fruit trees is the ability to graft onto dwarfing rootstock. Although few avocado trees are dwarf trees, almost all citrus trees for home gardens are grafted onto dwarfing rootstock that keeps them more compact and proportionate to home gardens. Most deciduous fruit trees are similarly grafted onto semi-dwarf rootstock.

Live Christmas Trees Eventually Mature

Most conifers are not so compact.

Christmas trees grow on farms. They are an agricultural commodity. Their unnatural and intensive cultivation is no asset to any associated natural ecosystem. Their harvest does not deprive ecosystems of natural components. Live Christmas trees are at least equally as unnatural. Their cultivation involves more synthetic materials and unnatural irrigation.

There should be no shame associated with the procurement of cut Christmas trees. They are merely cut foliage that is significantly more substantial than that which accompanies cut flowers. Furthermore, live Christmas trees are not an ecologically responsible option. They are merely potted plants that can be difficult to accommodate within home gardens.

That certainly should not invalidate the appeal and potential practicality of live Christmas trees. With proper maintenance, other potted plants, such as houseplants, can grow and perform for many years. Since live Christmas trees are coniferous species that get rather large, they demand more attention. All are not necessarily totally unmanageable though.

Some compact conifers, such as dwarf Alberta spruce and compact cultivars of Colorado blue spruce, can remain within pots for many years. They need either larger pots as they grow, or occasional root trimming if they stay within their same pots for a few years. Their roots outgrow pots as slowly as their canopies grow. They also require diligent watering.

Unfortunately, the most common of decorated live Christmas trees that are available from supermarkets are also the most problematic. Most are either Canary Island pine or Italian stone pine, which grow surprisingly large for such seemingly innocent small evergreens. They very often go into compact gardens, where their bulky roots displace infrastructure, such as pavement and turf grass.

Contrary to popular belief, planting live Christmas trees in the wild after Christmas is not a practical option. Because their roots were confined to pots, they rely on irrigation while they disperse roots into the ground. They can not survive without irrigation after the rainy season. Besides, trees that are not native could be detrimental to the native ecosystems.

Getting an early start to winter pruning may have certain advantages

Without specialized pruning, fruit trees become sloppy and unable to sustain all of their fruit.

As long as it gets done well before buds begin to swell late in winter, the meticulous and specialized pruning that deciduous fruit trees and roses require during winter dormancy does not need to be done immediately. Here where the climate is so mild, some roses may still be blooming. The main advantage to getting an early start is that those of us who have many fruit trees and roses in need of pruning have more time to get them all done within the proper time.

If it helps to start pruning early, it is best to prune fruit trees and roses in the same order that they go dormant and defoliate. The ‘stone’ fruits (those of the genus Prunus, that have large pits known as ‘stones’), like apricots, cherries, nectarines and peaches typically defoliate earlier than the ‘pomme’ fruits, like apples, pears and quinces. Modern ‘carpet’ roses may not defoliate completely, so can be delayed until after all the bare roses get pruned, but may eventually need to get pruned while still partially foliated.

The specialized pruning that deciduous fruit trees and roses need is serious business. Those who do not know how to do it properly should learn about it before actually doing it. Improper pruning of fruit trees can inhibit production and damage the trees. Roses are not so easily damaged, but will get overgrown and not bloom as well if not pruned aggressively enough. (This sort of pruning will be a topic later in the season.)

Like fruit trees and roses, other trees and shrubs that need pruning prefer to be pruned while dormant through autumn and winter. Deciduous trees and shrubs are obviously dormant while bare, but realistically, are ready to be pruned when their foliage is no longer green.

Evergreen plants are not so obviously dormant, but will be as dormant as they get through winter. This would therefore be a good time to prune to eliminate pine limbs that are too low. If pruned a bit early, the pruning wounds will get weathered more through winter and consequently bleed less through spring.

Winter Berries Attract Migrating Birds

English hawthorn is like deciduous firethorn.

Bloom and colorful foliage provide most of the color besides green within home gardens during spring and summer. Deciduous foliage becomes more colorful for autumn. Winter berries and a few other lingering fruits become more colorful as deciduous foliage sheds through winter. All this color adheres to precise schedules within a collective ecosystem.

Many plants exploit wildlife. It is how they compensate for their immobility. Many provide incentive for the services that they desire from the wildlife that they exploit. For example, after enticing pollinators with fragrance or color, flowers happily exchange extra pollen or nectar for pollination. Many plants provide edible fruits in exchange for seed distribution.

It is no coincidence that so many different winter berries ripen through autumn for winter. They provide sustenance to many migratory birds who rely on them. Overwintering birds who compete with migratory birds appreciate their efforts as well. Such winter berries are small but abundant, for ‘grab and go’ convenience. Bright color is the best advertisement.

Some people appreciate how winter berries attract birds and squirrels into their gardens. Some appreciate the seasonal color of such berries more than the wildlife. Unfortunately, wildlife decides the outcome, and such outcomes are variable. It is impossible to predict if berries will disappear as they ripen, or linger as they deteriorate through most of winter.

Firethorn is likely the most familiar of the winter berries here. It seems to be more prolific with its brilliant red berries than any other species. Some old fashioned cultivars produce bright orange or perhaps even bright yellow berries. Some sorts of cotoneaster resemble firethorn, but with subdued rusty or orangish red display for less refined woodsy gardens.

Toyon, or California holly, is most prolific with winter berries where it grows wildly without pruning. It gets big though. Real hollies, which are more popular in other regions, do not produce many berries locally, particularly since male pollinators are uncommon. English Hawthorn is a small deciduous tree that displays berries that resemble those of firethorn, but on bare stems.

Winter berries provide more color as autumn foliar color finishes.

Pyracantha, although inedible, is likely the most colorful of the winter berries here.

Seasonal color is as variable as the weather. Just as the many different spring flowers bloom differently every spring, and the autumn foliage color is different every autumn, the colorful berries and fruits that linger on many plants through winter respond to the weather. Then, the various birds and other animals that devour them do so at different times, and at different rates every year.

Pyracantha (or firethorn) is probably the most reliable for an abundance of brightly colored red berries. Old varieties with orange or even yellow berries are very rare, perhaps because they are comparably wimpy. Unfortunately, because they are so colorful, and also because they ripen before many of the migratory birds have gone, the berries often get eaten by birds soon after they ripen.

Berries of the various cotoneasters are not quite as colorful, and many ripen slightly later, so they are not so efficiently stripped by birds. Cotoneasters are now more popular than related pyracantha because there are so many varieties with so many different growth habits. Larger types grow into large shrubbery while prostrate types grow as ground cover. Cotoneaster also has the advantage of lacking thorns.

The native toyon can provide large clusters of similar red berries, but only if it is allowed to grow somewhat wildly. It is unable to bloom and subsequently produce berries if regularly shorn. Yet, even in the wild, toyon is unpredictable. Because damp weather can cause berries to rot before they ripen, toyon may be unproductive for many years, and then produce remarkably colorful displays of berries when least expected.

Hollies are the most familiar of colorful winter berries, but are not as colorful as pyracantha or the various cotoneasters because they are almost never provided with male pollinators that they require to develop fruit. Fortunately, their remarkably glossy and prickly foliage is appealing alone.

Flowering crabapples are grown for their impressively colorful pink, white or nearly red spring bloom, but some types also produce sparse and minute red, orange or even yellow crabapples that stay after the foliage turns yellow and falls. English hawthorn lacks the flower color of flowering crabapples, but has more abundant and colorful red or orange berries that linger into early winter after the foliage is gone, or at least until birds find them.

Firewood Is Old Fashioned Technology

Cut firewood needs to be split.

Chimney clearance pruning is easy to overlook nowadays because, for various reasons, chimneys are becoming obsolete. Modern homes lack them completely. Some chimneys of older homes succumbed to earthquakes. Because of simpler and cleaner alternatives for heat, remaining chimneys and their fireplaces, as well as firewood, are almost passe.

Ironically, chimineas and fire pits have become a fad. Most modern fire pits use propane for fuel, but a few use firewood. Although such fire pits and chimineas burn less firewood than fireplaces, they are ridiculously less efficient. Their warmth simply escapes into the atmosphere. Relative to the volume of wood they burn, they generate much more smoke.

Nevertheless, whether for fireplaces, wood stoves, fire pits, or chimineas, firewood is not yet completely obsolete. Some households only rarely use small quantities for ambience fires. Some households still use more significant quantities to supplement home heating. A few households rely on firewood as their primary or exclusive source of home heating.

For unrelated reasons, the availability of firewood has declined with its demand. Orchard trees that were still relinquishing their space decades ago are now gone. Also, wildlands are now farther from large urban regions where most people live. Wood from demolished buildings is more likely to become chipped mulch than to become available as firewood.

Fortunately, most tree services sell firewood that is a byproduct of their work. Such wood is generally a mix of various species, so may include some degree of softwoods, such as pine. Rural tree services are more likely to be able to provide specific types of hardwood, and are also more likely to be able to deliver it. Their softwoods might be less expensive.

Tree services prefer to leave wood where they do tree work, and actually charge a bit for removal. Cut rounds of logs should be firewood length, but need splitting and seasoning. Inadequately seasoned or damp wood generates more smoke than properly dried wood. It should stay sheltered from rain. Palms and yuccas are impractical for use as firewood.

Too Much Water Is A Serious Problem.

Well, . . . this is an exaggeration.

The most common problem with landscapes that are maintained by maintenance gardeners is excessive irrigation. In fact, with very few exceptions, the only lawns that are maintained by gardeners that are not also irrigated excessively are too dry because the irrigation systems are not operational. Excessive irrigation is not only unhealthy for the landscapes, but costly.

Wasted water is obviously expensive, but also causes all sorts of expensive damage. Saturation of soil inhibits deep dispersion of roots, causing shallow roots to displace pavement. Shallowly rooted trees that are easily destabilized by wind can cause expensive damage, and are expensive to remove. Smaller plants that do not cause damage as they succumb to saturation and rot are still expensive to replace. The gardeners who get paid to maintain the landscapes should assume liability for the damages they cause, but instead charge to repair it! If they can not repair the damage, they typically happen to know someone who can.

Fortunately, those of us who maintain our gardens, or are at least involved with the maintenance, are not so generous with water. Although lawns need quite a bit of water, they also need adequate drainage. Besides, we tend to be more aware of the expense of water than gardeners are.

Now that it is autumn, irrigation needs to be decreased for various reasons. Rain will be providing more moisture as the seasons progress. While the weather gets cooler and more humid, and the days get shorter (less sunlight) not so much moisture evaporates. Most plants are either dormant or at least less active, so consume less moisture.

There are unfortunately no accurate formulas for decreasing frequency and duration of irrigation as the weather changes. It must be done by trial and error, by providing enough irrigation during dry spells without keeping conditions too wet. Of course, no irrigation is necessary during rainy weather, except only for plants that are sheltered by eaves. Hanging pots should be monitored because they are both sheltered from rain (if hanging from eaves), but also exposed to drying wind.

Also during autumn and winter, dormant plants need no fertilizer. That can wait until they wake up early in spring. Raking falling leaves from lawns, ground cover and low shrubbery is important though, since such debris shades the plants below while sunlight is already less abundant, and can also promote rot.

Debris Fills Gutters During Autumn

Falling leaves eventually become abundantly messy.

Autumn foliar color certainly is pretty while it lasts. Although less prominent locally than it is where cooler weather begins earlier, it is an asset to many home gardens. It generally appears a bit later within mild climates here, but might also remain suspended a bit later. Ultimately though, with enough wintry wind and rain, it eventually becomes foliar debris.

Evergreen foliage also contributes to the mess. It is likely less abundant than deciduous foliage is during autumn, but only because it sheds through more extensive seasons. For example, Southern magnolia sheds mostly through spring, as new foliage replaces older foliage. It then continues to shed additional debris throughout the year, including autumn.

Regardless of its various origins, foliar debris becomes more of a concern during autumn for two simple reasons. Firstly, and obviously, more of it accumulates during autumn than during any other season. Secondly, since autumn is the beginning of the rainy season, it is the most inconvenient time of year for such debris to accumulate within home gardens.

Roadside gutters, eavestroughs and their downspouts should drain efficiently. However, foliar debris can interfere with their drainage when it becomes most important. Roadside gutters are more accessible, so are easier to observe and clean. Eavestroughs and their downspouts may be beyond reach, but may need more cleaning if defoliation continues.

Foliar debris is unhealthy for turf, groundcover and shrubbery that it accumulates over. It inhibits photosynthesis by obstructing sunlight. It can also promote proliferation of fungal pathogens. This is why prompt raking is very important. Foliar debris can stain pavement and decking, and may be hazardously slippery. Behind chimneys, it can promote decay, and possibly become a fire hazard.

Pumpkins After Halloween

Jack o’ lanterns and pumpkins will soon meet their gory demise now that Halloween is over.

Pumpkins are both the biggest of the common fruits, and also the most wasted. So many of us bring at least one into our homes for Halloween, only to discard them afterward. Not many of us actually bake or make pies from ‘used’ pumpkins. However, those of us who like to can or freeze fruit and vegetables can really take advantage of this tradition by politely collecting jack o’ lanterns from neighbors, or getting unsold pumpkins from markets for very minimal expense. (Pumpkins are ‘low acid’ fruits that need to be canned with a pressure cooker.)

The somewhat small brownish ‘sugar pie’ pumpkins that are sold for pies are of course the best, with the richest flavor and meatiest shells. The common bright orange pumpkins used for jack o’ lanterns are not as meaty and lack flavor, but are certainly worth the price if they are free. White pumpkins can be just plain bland; but with enough sugar and spices, can make decent pie. The deeply furrowed green or gray pumpkins might likewise taste better than they look, but who knows? I certainly have not tried one yet.

Because the jack o’ lantern pumpkins have such thin shells, my neighbor and I prefer to cut them into pieces and steam them before peeling them. It is a messy job, which is why she has me do the peeling part of it. Before steaming, she cuts out any parts with candle wax (on the bottom) or soot (on the top). Once peeled, the pulp is ready to be pureed, and then frozen, canned or baked directly into pies.

Those of us who do not indulge in freezing, canning or baking of ‘recycled’ pumpkins can either give our pumpkins to neighbors who do, or must otherwise dispose of them. On the compost pile, pumpkins should be chopped up and spread out so that they do not mold and rot as much as they would if left intact. Chopping them with a shovel should be adequate. By now, there should be plenty of fresh leaves on the compost pile to spread pumpkin parts out over.

If fireplaces or wood stoves have been used already, the resulting ash can be spread out with chopped pumpkin, to inhibit mold in compost piles. Ash also deters snails. Just be certain that only dead ash gets scattered, without any embers, and that it gets spread thinly enough so that it does not become a mucky mess that actually inhibits composting.