Mandarin orange, Citrus reticulata, and nuts are some of the more traditional goodies for Christmas stockings. In Northern Europe centuries ago, nuts from the Americas were still exotic treats. The availability of perishable citrus fruits from Mediterranean regions relied on expensively efficient shipping. Consequently, citrus fruits were almost like delicacies.
Even when shipping was slow, Mandarin oranges ripened in time to arrive by Christmas. However, they needed fast shipping because they are more perishable than other citrus. They are innately more prone to oxidation because their rind and segments fit so loosely together. Of course, that is why they are so delightfully easy to peel, pull apart and share.
Mandarin oranges are smaller, more oblate, brighter orange, but also more variable than common sweet oranges. Among their many cultivars, their smaller leaves and thorniness are likewise variable. Very few very old trees grow taller than fifteen feet. Tangerines are merely barely genetically distinct Mandarin oranges that developed within the Americas.
Chilled lemonade certainly is nice when the weather gets warm during summer. Orange juice also seems to be more appropriate to warm weather. In fact, most citrus fruit seems to be more summery than wintery. Yet, most of it ripens through winter. Mandarin oranges are more perishable than most other citrus fruit, so are best long before warmer weather.
Citrus trees are defiantly contrary to the deciduous fruit trees that produce fruits of spring and summer. Not only does their fruit ripen during opposite seasons, but they also prefer pruning during opposite seasons. Many need no pruning or only minor grooming as they age. Any necessary pruning should happen after the last cool or frosty weather of winter.
Citrus fruit is not as perishable as spring and summer fruit are. Mandarin oranges oxidize within a month or so only because their rind is so loose. Other citrus fruit remains fresh in the garden for months, even through warm weather. Some actually improves with a bit of aging. For fruit that lingers late, vermin are more likely to be a problem than deterioration.
Slow deterioration is a major advantage for such abundant citrus fruit. There is less rush to collect more after collecting too much. For more sporadic production, many cultivars of citrus bloom sporadically prior to and after their primary season. ‘Eureka’ lemon is not too overwhelmingly productive in season, but before and after, provides a few more lemons.
Citrus fruit are remarkably diverse. Many are best simply for fresh eating. Many are better for juicing. Some are best for other culinary applications. Mandarin oranges and oranges are basically sweet. Lemons and limes are basically sour. Grapefruits are basically bitter. Citrus fruit exhibits a prevalence within combination of these three basic flavor elements.
Citrus trees are as variable as the citrus fruit that they provide. Almost all are dwarf trees, which stay more compact than standard orchard trees. However, ‘Eureka’ lemon, ‘Marsh’ grapefruit and ‘Sanguinelli’ blood orange can eventually get as big as small shade trees. ‘Meyer’ lemon, kumquats and most Mandarin oranges remain much lower and shrubbier. Some are thornier than others.
Cherry, Prunus avium, is one of the more popular fruits of summer. However, winter is the season for planting new trees and pruning mature trees. Pruning is comparable to that of other stone fruits, but to a lesser degree. Their sweet fruits are typically less than an inch and a half wide, so are relatively lightweight. Docile trees may not need annual pruning.
Home garden trees with dwarfing rootstocks should grow no taller than about fifteen feet. Some stay less than ten feet tall. Orchard trees with standard rootstock grow significantly taller. Wild or feral trees can grow forty feet tall, with their fruit beyond reach. Old cultivars mostly require another compatible cultivar for pollination. Some modern cultivars do not.
Cherry fruits are mostly rich deep red, but can be dark blackish red or pale orangish pink. Early spring bloom is brief but profuse and splendidly clear white. Three to four inch long leaves that are deep green through summer become bright yellow or golden yellow prior to defoliation during autumn. Even the silvery young bark of some cultivars is appealing.
Adding new fruit trees to a garden is reasonably easy. Maintaining them properly as they mature is more of a challenge. Centuries of extensive breeding to enhance production of such trees has also increased their reliance on horticultural intervention. Most deciduous fruit trees consequently need specialized dormant pruning during their winter dormancy.
Without adequate dormant pruning, most deciduous fruit trees are unable to support their unnaturally large and unnaturally abundant fruit. Dormant pruning actually enhances the size and quality of fruit. However, it also limits the weight of excessiveness, and confines it to sturdier branch structure. It concentrates resources into fewer fruit of superior quality.
Dormant pruning, or winter pruning, likewise concentrates resources into more docile but healthier vegetative growth. It eliminates or at least diminishes the 4 Ds, which are dead, diseased, damaged and disfigured growth. Confinement of potentially rampant stems not only improves structural integrity, but also limits wasteful production of unreachable fruit.
Almost all deciduous fruit trees, and most nut trees, require specialized dormant pruning. So do grapevines, kiwi vines, berry canes and roses. Evergreen fruit trees, such as citrus and avocados, are exempt for now though, since such pruning promotes new growth that is vulnerable to frost. Most of such trees do not require such aggressive pruning anyway.
Almonds, apricots, cherries, nectarines, peaches, plums, prunes and all their hybrids are stone fruits of the genus Prunus. Almonds are actually seeds, or stones, of leathery fruits that are merely hulls. Various stone fruits need various degrees of similar pruning. Heavy peaches need aggressive pruning. Lightweight cherries might need only minor trimming, or no pruning at all.
Apples, pears and quinces are pomme fruits that, like stone fruits, need various degrees of similar pruning that conforms to their distinct characteristics. Persimmons, mulberries, pomegranates and figs each need specific types of pruning as well. Familiarity with each of the dormant pruning techniques that each fruit tree in the garden requires is essential.
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.
Of all the stone fruit trees like apricot, plum and cherry, none need more aggressive and specialized pruning while dormant in winter than peach, Prunus persica. The distinctively fuzzy fruit is so big and heavy that the weight of too much fruit tears limbs down. Pruning not only limits fruit production, but improves structural integrity, fruit weight distribution, fruit quality, and tree health. Mature trees should be kept less than ten feet tall, but often get twice as tall with much of the fruit out of reach.
It is embarrassing when my mother teaches me a practical gardening technique that I should have known about, especially if the particular technique is as simple and downright silly as what my mother does to protect ripening fruit from squirrels. A friend of hers suggested it; and it seems to be significantly more effective than the few fancier ideas that I recommended.
I should first mention that there is nothing new about repelling animal pests with effigies of other animals that they are afraid of. Scarecrows and stuffed snakes and owls have been around for centuries. As the name implies, scarecrows scare crows who perceive them to be potentially troublesome people. Rats and terrestrial rodents avoid snakes. Squirrels and some birds are afraid of owls.
When I was in about the fourth grade, I remember that National Geographic World magazine (which is now National Geographic Kids) featured a silhouette of a predatory bird that could be cut out and taped to windows to deter birds that might otherwise break their necks as they tried to fly through the clear glass. The associated article explained that the cut-out silhouette was effective because birds instinctively knew what to fear. A silhouette of a harmless seagull would not have been as effective.
However, some deterrents are not so specific, but instead rely on the fear of the unknown. Beach balls outfitted with decals of huge eyes look weird in the garden, but work because so many birds have bird brains that think such contraptions are big, scary and possibly predatory animals. Flash tape and old compact discs work simply because birds do not know what the reflected flashes are.
Scarecrows and other inanimate effigies should be relocated occasionally so they seem to be alive. They should stay near what they are in the garden to protect, and not loiter when it is gone. For example, if protecting ripening fruit, they should leave after the last of the fruit is gone. Otherwise, the target pest animals realize that they are fake or dead. Beach balls, flash tape and compact discs are more animated, so need not be moved so much, if at all, but are too tacky to stay all year.
All this may seem complicated, but can be simple enough for my mother to master with . . . well, allow me to explain.
Pierre Francois is a cute, fuzzy and seemingly French plush toy bunny made in China, who knows all about protecting ripening fruit from squirrels. (‘Stuffed animal’ is no longer politically correct.) After seeing how expensive a fake owl would be, my mother put Mr. Francois in the peach tree. He and his sort are free if borrowed (stolen) from the grandchildren, or very cheap at garage sales or thrift stores. Although cute and soft to us, Mr. Francois is big, intimidating and unfamiliar to squirrels. Before the squirrels get acquainted with him, the peaches will have been harvested, and Pierre Francois will have been reassigned to an apple tree.
Compared to the common passion flower, the three inch wide red passion flower, Passiflora manicata, is more colorful with cherry red flowers, but does not so prominently display the weirdly distended floral parts that passion flowers are known for. Bloom is not as profuse either, particularly among vigorous vines.
However, red passion flower vine has the advantages of somewhat more resilient and greener foliage, and sturdier vines that can climb almost to thirty feet high. It grows so vigorously that it can be surprisingly overwhelming, even if pruned severely or cut to the ground at the end of each winter. It is not so rampant in light shade.
Copies (new vines) are easy to propagate by layering, which involves merely burying a section of vine while still attached to the parent vine until it develops enough roots to be separated. The buried section should be at least a few inches long. At least a few inches of the tip of the vine should extend beyond the buried section.
The fruit of red passion flower vine is considered to be toxic, but often gets eaten anyway. Fortunately, fruit rarely develops.
The mostly white and blue common passion flower likely remains the most popular. After all, it is the weirdest. Elaborate and disproportionate floral parts imply that it is of another planet. Red passion flower, Passiflora racemosa, although less peculiar, is perhaps a bit more colorful. Its brick red flowers bloom randomly for as long as weather remains warm.
Flowers are about three or four inches wide. They develop in open racemes that seem to spread out somewhat evenly over the exterior of their foliage. Bloom is not profuse, but is somewhat continuous until autumn. Newer flowers replace older flowers within the same racemes. Leaves are as wide as their flowers, with three blunt lobes and axillary tendrils.
The lushly evergreen foliage can get shabby through winter, or completely ruined by just mild frost. It regenerates vigorously though. Aggressive pruning as winter finishes delays bloom, but promotes vigorous growth. Vines can potentially reach more than twenty feet. Fruit is rare without manual pollination. Fruit flavor can be bland without tropical warmth.
Winter is the primary season for citrus fruits. Some ripen significantly earlier. Some ripen significantly later. Many citrus trees continue to produce a few fruits randomly throughout the year. Nonetheless, citrus fruits are collectively most abundant during winter. It seems odd that trees that are vulnerable to frost are so productive during the coolest of weather.
Citrus trees are fortunately only marginally susceptible to frost in only the cooler climates here. They mostly recover from minor damage where they get a bit too much chill. Those in coastal climates may never experience damaging frost. Some types of citrus are more resilient to frost than others. Vulnerable citrus trees may need frost protection when new.
Home garden citrus trees are different from orchard trees. Most orchard trees, particularly older trees, are ‘standard’ trees. They grow on standard rootstock that allows them to get larger, and therefore produce more fruit than ‘dwarf’ trees. Most home garden citrus trees are ‘dwarf’ trees. They grown on dwarfing rootstock that keeps them dense and compact.
Furthermore, the many cultivars of citrus that are available for home gardening are more diverse than those that commonly grow in orchards. ‘Lisbon’ lemon is very profuse within season, so is preferable for orchards. ‘Eureka’ lemon, although a bit less productive, may be a preferable option for home gardens because it produces a few random fruit all year.
Now that citrus are in season, some last longer than others. Grapefruit can hang on their trees for months. They actually develop richer flavor with mellowing tartness as they age. Conversely, Mandarin orange and tangerine are the most perishable citrus. Because the rind is loose, their pulp within begins to oxidize after ripening. Lime eventually gets pithy.
Although this is the time of year to enjoy fresh citrus fruits, it is not the season to do much else with citrus trees. Pruning and application of fertilizer will be more timely after winter. Premature pruning or use of fertilizer is likely to stimulate premature growth. Such growth either languishes through cool weather, or succumbs to mild frost.