Keep Your Evergreens Growing Steadily

When you are planning to grow evergreens, a few pointers will guide you on your way to maximum success with these richly rewarding woody orna­mentals. They are about the most undemanding plants you can grow, but it pays to give them the conditions that are best suited to their welfare. This includes providing congenial soil, feeding, watering, and covering them with a friendly mulch to help conserve moisture and hold down the soil temperature. Judicious pruning will definitely enhance their beauty.

SOIL

First let us consider the cone-bearing trees (conifers), such as Pines, Hemlocks, Spruces, Firs, Junipers and Cedars. These evergreens, as well as many others belonging to the coniferous group, show a preference for ground that is moderately light, friable, and well drained. The soil should be neither too heavy nor too sandy. Heavy clay ground is undesirable be­cause it is more difficult for the roots to penetrate it, and the soil aeration is inadequate. This kind of land can be ameliorated by incorporating into it generous quantities of sand and peat moss. On the other hand, a soil that is overly sandy is not satisfactory, since it is not sufficiently retentive of moisture or minerals. Soil of this type can be improved with the addi­tion of clay, or a combination of well-rotted cow manure and peat moss. This will increase the water-holding capacity of the ground and will help to keep the evergreens from drying out.

Conifers grow best in soil that is neither too alkaline nor too acid; on the other hand, the majority of broad-leaved evergreens will not thrive unless the soil is sufficiently acid. Fortunately in most instances a congenial soil can be maintained with little effort by the use of acid fertilizers, and by working into the ground liberal amounts of peat moss, oak leaf mold, or commercial humus. In the parts of the country where the soil is defi­nitely alkaline, it is necessary to increase acidity at frequent intervals, and even so it is difficult if not impossible, to overcome the natural condition of alkalinity.

Around the foundation of newly built houses, the chances are that con­crete, plaster, rubble, and debris of all kinds have been left and covered with a rather thin layer of soil; these should all be removed and replaced with rich top-soil or compost.

PLANTING

The best seasons for planting evergreens are either the early spring or the fall. Spring planting should be done as soon as the ground is in a worka­ble condition. The least propitious time for moving evergreens is later in spring when the plants are clothed with their tender, succulent new growth. At that season wilting is difficult to avoid, and there is risk of breaking the young shoots. Furthermore, the plants are dislodged from the ground at a time when they are drawing heavily on the nutrients and moisture in the soil for sustenance. In the autumn, September and October are ideal planting months in the vicinity of Philadelphia. The time naturally varies with climatic conditions. A good rule to follow is to put the trees in the ground 6 or more weeks before real winter begins. In mild climates the planting season commences in the fall and continues until the excessive heat of spring arrives. (For specific advice on the best planting season for your locality, see the Report on Evergreens from the States.) Some growers contend that evergreens can be planted every month of the year. Provided the weather is not too hot and dry, and if every care is taken in the plant­ing procedure, this can sometimes be done successfully.

In moving plants out of season, spraying the branches and the upper surfaces of the leaves with Wilt-Pruf may be of value. Wilt-Pruf is a plastic which checks loss of moisture from the foliage. Its valuable points are that it allows the gases to escape and does not hinder normal growth. The effect of this spray lasts for about a month, and it carries the plants through the most difficult period of readjustment. If you are moving to a new home, there may be special plants that you cherish and would like to take with you; if this transplanting must be done in the heat of summer, Wilt-Pruf is a real boon, since it lessens the risk considerably.

When planting must be deferred for several days after the evergreens have been delivered, set the plants in a shady, protected spot and keep the balls of earth around the roots moist. Unlike the deciduous flowering shrubs which can be placed in storage during dormancy, the roots of evergreens must never be allowed to dry out, therefore it is not advisable to store this group of plants.

For successful results it is of utmost importance to do the actual planting with care. The step-by-step procedure is as follows:
1. Make generous planting holes. These should be deeper and wider than the ball of earth around the roots. Twice the diameter of the ball, and one and a half times its depth is a good rule to follow. Loosen the soil at the bottom of the holes with a pick, spading fork, or grubbing hoe, then throw in enough well-pulverized, fertile soil to give the plants a good rooting medium, and firm it well to prevent too much settling. At planting time no commercial fertilizer should be mixed with the soil because it can cause burning if it comes in contact with the roots. This is the case also if manure that is not thoroughly spent is used; well-rotted cow manure is the exception, provided it is 2 or more years old, and is practically the consistency of peat moss. If the soil is naturally deep and fertile, it will not need amelioration.

Set the evergreen in the hole so that it will stand no more than ½ to 1 inch deeper than it stood before. The depth that it was planted in the nursery can be determined by the soil line on the main stem. After the evergreen has been placed the correct depth, cut away the burlap along the sides and remove it; better still, take away all the burlap provided this can be done without breaking the ball. An important point to bear in mind is to avoid breaking this ball because it is far better not to dis­turb the roots of evergreens.

Fertile top-soil or compost are ideal for use in filling the hole. Work the earth firmly around the ball of roots by either tramping or by using a tamper. Repeat this firming frequently as the soil is thrown in. Be sure that no air pockets are lefl. When three quarters of the hole has been closed in with earth, then fill the depression with water; when this has been absorbed, finish filling the hole with soil until it is brought to ground level. This top layer of soil is not firmed, in order that subsequent water­ing and rainfall can seep through more readily. The chances are that a week or so after the planting has been finished the soil will have set­tled; if so, add enough earth to bring it up to ground level. After the planting has been completed, make a saucer of soil around the evergreen and water the plant again; this saucer will act as a catch basin, and it should be made just inside the outer spread of the branches. It is a decided advantage to keep this saucer during the first growing season.

Newly planted trees that are 6 feet or more in height should be given support with guy wires to keep them straight, and to prevent the roots from becoming dislodged before they take firm hold of the ground. For guying purposes heavy wire is used. To protect the tree a piece of hose is placed around the trunk about halfway up and the wire is passed through it; a separate piece of hose is used for each wire, there are usu­ally three of these. These guy wires are anchored to the ground with three stout stakes, called "dead men." These stakes are placed a foot or so beyond the outer spread of the tree, and are driven firmly into the ground at equal distances from each other; the stakes should be about 2 to 2½ feet long, and they should be run into the ground to a depth of 18 inches to 2 feet, the depth depending on the size of the tree to be supported. The wires must be kept taut and tightened from time to time if they sag. This support will be required throughout the first year after planting.

WATERING

After the evergreens have been set out and have had their first soaking, future waterings will depend on various factors. The amount of rainfall is obviously an important consideration, also the temperature. Frequent water­ing is needed in the spring because the warmth of the sun dries out the soil unbelievably fast. Less watering is required in fall since the ground is cool and damp. The kind of soil is another factor to take into account. Soil that is heavy is naturally more retentive of moisture than ground that is porous and light in texture; the latter, of course, drains more rapidly and more frequent watering is needed.

There are no set rules as to the amount of water to be given. Observa­tion is the best teacher. After a new planting has been made, the evergreens probably should be watered on an average of two or three times a week until they become established. Throughout the first season in their new quarters, it is especially necessary that they should never be allowed to suffer from dry spells; under such circumstances watering must be care­fully attended to. Established trees will not usually require watering except in periods of drought. On the other hand, shallow-rooted plants, such as many of the broad-leaved evergreens, should never be allowed to become too dry.

Adequate watering soaks the ground to a depth of at least 6 inches. Light sprinkling does more harm than good as the water does not reach the lower levels, therefore a deep root system does not develop. With shallow water­ing the roots near the surface will grow, but the result is that even in mod­erately poor weather the surface will become dry and the plant will die. Deep watering works the opposite way, and even if the surface dries and the roots close to the surface die, still the plant survives, since the deeper roots draw on the moisture in the lower levels.

When watering evergreens, water not only the ground but also the foliage and give them a good drenching. Never water when the sun is shining on the leaves as it might cause burning. A rough guide to follow as to the amount of water required is to puddle the soil until it no longer seeps into the ground rapidly. A question often asked is, Can watering be overdone? The answer is yes. If the soil is waterlogged over a long period of time, there is danger of suffocating or killing the feeding roots. To avoid this con dition a safe rule to follow is to allow the soil to become a little on the dry side between waterings. The best way to water trees is to allow the water to trickle slowly on the ground through the hose for a few hours; the posi­tion of the hose should be moved from time to time in order to distribute the flow evenly.

If the rainfall is below average, safeguard your evergreens by watering them at intervals of two weeks commencing in August. Unlike deciduous trees and shrubs that shed their foliage in the fall, evergreens retain most of their leaves all year round and therefore they are constantly giving off moisture. They should be adequately watered before frost closes the ground, or they may dry out and be in danger of winter-killing; the loss of moisture in the cold months through transpiration might otherwise exceed the intake of water.

PRUNING

A regular program of pruning will help to keep the evergreens shapely, compact, and luxuriant. A light trimming every year is far better practice than a drastic one every few years, and can spell the difference between success and failure. When pruning is neglected over a period of time, the growth becomes misshapen and spindly, and several years of pruning will be required before the former shape is regained. In fact, when it is neces­sary to cut into the old wood there is often a question as to whether or not the evergreen can be restored. In some instances it is much wiser to dis­card the old plant and replace it with younger stock.

The pruning of evergreens commences in the early stages of their exist­ence. If you purchase your material from a reliable source, the nursery-grown plants will be dense, well shaped, and bursting with vigor. Evergreens that are not nursery grown are those that have been collected from their native haunts, and disposed of soon after the shipment has been received by the nurseryman. These plants usually require a little shaping up after they have been planted. The first step on the road to success is to select plants that are healthy and symmetrical.

The problem of the home-owner is to keep the new planting sturdy and dense in its growth. The pruner holds in his hands the direction of the future growth of the plant. It is a fascinating part of the routine culture, and a challenge to the artistic ability of the one who wields the pruning shears. Here again experience is the greatest teacher, but the beginner can start to master the work by learning some fundamental principles.

First of all equip yourself with well-sharpened hand pruners, a pruning knife, and a saw; the latter will be needed if large limbs are to be removed. These major cuts should be made close to the main trunk or stem; how­ever, if it seems desirable to retain a portion of the branch, then the cut should be made about half an inch above a leaf or a bud, which is kept for future growth. Clean cuts are the rule, as shaggy surfaces are entering wedges for disease organisms. Large wounds of broad-leaved evergreens must always be protected with tree paint. Paint is not used on conifers because the resin in the wood covers the wound rapidly. The most effec­tive pruning preserves the natural form characteristic of the individual plant, unless the evergreens are to be sheared for hedge purposes. Above all, do not fall into the common error of turning pyramidal and graceful evergreens into stiff, moundlike shapes. This kind of trimming results in ruining the artistic effect.

Most broad-leaved evergreens are best pruned in early spring, just before or soon after the new growth has commenced. In the Philadelphia area the approximate period is March to early June. The species that bear effec­tive flowers early in the season should be cut directly after the blooms have faded; in the case of those which flower later—on wood of the current sea­son's growth—the trimming is done while they are still dormant. The annual grooming of broad-leaved evergreens simply consists of cutting back the branches slightly here and there to encourage growth at the base of the plants and to improve their form. All dead and diseased wood and weak branches should be removed, dead wood encourages diseases, and the ad­vantage of discarding weak branches is to concentrate the flow of sap on a lesser number of shoots.

Evergreens that have a branching habit from the ground up (such as Laurel) will sometimes lose their lower leaves and become straggly and unsightly. In such instances renovation is in order. This is done in early spring before growth starts, by cutting the branches back to within a few inches of the ground. This will force the development of a new, stocky top-growth; however, it will take at least two years or more for the shrub to develop to any appreciable extent. Do everything possible to keep the new shrub growing steadily by fertilizing, mulching, and watering in dry weather. Remove the flowers as soon as they fade, because much of the strength of the shrub will be expended in the production of seed instead of in growth.

Spruces, Firs, Pines and other trees with spreading branches that grow more or less in horizontal layers, require a different treatment. In these species a cluster of new growth will appear at the end of each branch in spring; to make a denser growth simply cut off one half to three quarters of the center shoot of each cluster. Make the cut a little above one of the dormant buds; these buds will then grow and thicken the tree the follow­ing year. In the case of Pines, the center of each terminal cluster of new growth is pinched out in spring.

In nurseries pruning is done at almost any season. If the pruning is to be severe, then the best time to do the work is in late winter or in the early stages of the new growth; this latter appears at different times according to the locality.

If storm damage, insects, or other causes destroy the leader of the trees, the defect can be remedied. This is done by selecting a shoot close to the top of the tree, and training it in an upward position; the shoot is held in place by tying it to a splint with soft string. The splint may be removed when the new leader is in no further need of support. When more than one leader appears, allow only one to remain; several leaders detract from the natural shape of the tree. Since the trees begin to enter their dormant period about the first of August, it is inadvisable to prune at that time or later because if the cutting is done when the season has advanced, it stimu­lates growth which does not have a chance to mature sufficiently to with­stand the low winter temperatures. Continue to prune every year until the trees become too tall to make it practical.

When the leader of the tree shoots upward 2 feet or more in one season, if half of the current season's growth is cut off, the space between the branches will be shortened and a denser effect will result. This cutting is best done in late winter before growth starts.

Photo: Roche
Evergreens of different heights and textures make a garden that can be enjoyed every day of the year. (Garden of Mr. William Gotelli.)

Hemlock, Arbor-vitae, False-Cypress, Juniper, Cedar, and other ever­greens with fine-leaved, feathery foliage are also best pruned either in late winter or in the spring when the new growth begins to develop. If only a light pruning is needed, it can be done at any time. The usual practice is to cut off about 2 inches of the tip ends and to trim back any branches that are out of bounds; the shoots should be cut in irregular lengths in order to avoid a stiff, formal effect. If trimmed in spring, approximately one half of the new growth is removed. When greens are desired for house decoration at the Christmas season, it is not harmful to prune evergreens at that time, provided it is done in moderation. The pruning of this feathery type of evergreen will cause it to break out in numerous points, which ob­viously increases the density of the plant. If pruning is neglected it is difficult to restore its shapeliness.

A carefully selected grouping of evergreens sets off this house to best advantage. Arbor-vitae, Red-cedar, and Pyracantha are used where height is needed. Pfitzer's Juniper is planted in the foreground.
Photo: J. Horace McFartand Company

In the case of formal hedges the pruning is different, since the objective is to keep the lines symmetrical rather than irregular. Ordinarily repeated light trimmings will be required during the summer months.

If evergreen trees are planted in locations that cramp their development, the situation can be helped temporarily by pruning the roots before growth commences in spring. This is done by thrusting a sharp spade vertically into the ground to a depth of 1 foot, thus severing a portion of the root system. The cutting is made around the circumference of the trees just inside the outer spread of the branches. Avoid pruning the roots too close to the trunks, otherwise the plants may not survive the shock. This root pruning checks the growth by decreasing the plants' supply of soil nutri­ents and moisture. At the same time that the roots are cut, the top-growth of the evergreens should be pruned back severely. (For specific advice on the best time to prune in your locality, see the Report on Evergreens from the States.)

MULCHING

A mulch is a loose covering which is placed over the surface of the soil. This is especially important for newly transplanted stock, and in most instances it is a decided advantage to maintain a year round mulch. A 2-inch covering is the usual depth to use during the summer; whereas in northern winters a deeper mulch is advisable. (See Winter Protection, later in this chapter.) Acid-loving plants react well to a mulch with an acid content, such as peat moss.

In selecting the kind of mulch to use, an important concern of home gardeners is to use one which does not detract from the appearance of the garden. The soft brown color of buckwheat hulls are preferred by many since they are light, easy to handle, and efficacious. These check the evapo­ration of moisture from the soil, and do not prevent the water from pene­trating into the ground. Peat moss adds definitely to the well-groomed appearance of the garden. The disadvantage of its use is that it must be kept moist; when it dries out it becomes crusty, with the result that water runs off it instead of being absorbed into the soil. This drawback is remedied by stirring the surface lightly with a rake before a rainfall or a watering. It is a good idea to purchase your peat moss early in the spring and to stand it in the open. As soon as it is received, remove the burlap and break up the bale with a spading fork, so that the rain water will be absorbed; in fact it should never be applied until it is well moistened and crumbly. The acidity of peat moss makes it splendid for use on all acid-loving ever­greens, such as Rhododendron, Laurel, and other members of the Ericaceae. Aged leaves will often pack into tight layers and water drains off rather than through them. Shredded, partially decomposed leaves make an excel­lent mulch. Mice live under heavy mulches.

Evergreens of this group are also benefited by a mulch of oak leaves; however, as far as appearance is concerned, this is best suited for winter protection. In spring when the oak leaves are removed and thrown on the compost pile, those that are partly decomposed are left on the soil to add to the organic content.

Other mulch materials worthy of mention are mushroom manure, Cypress needles, Pine needles, and compost. Sawdust is also used a good deal, and it will not detract from the appearance if Red Cedar or Red­wood sawdust—both brownish in color—is used. Unfortunately, however, the use of sawdust results in depletion of nitrogen as it breaks down; con­sequently when it is used, an annual fertilizing should be given with a formula that contains nitrogen.

When evergreens are used in borders or in the foundation planting, a living mulch is very popular; as its name implies, this type of mulch is made of plants, and here again is still another use for ground covers, such as Euonymus fortunei, Pachysandra, or Periwinkle; they not only provide the needed protection, but are also very ornamental. The disadvantage of using a covering of this kind is that the plants draw on the soil nutrients and moisture, thus competing with the shrubbery planting. This can readily be overcome by occasional feeding and watering, the exact amount required depends on the soil conditions. When a living mulch is used it is necessary to thin it out each season so that the plants will not grow into the hearts of the bushes. (For specific advice on mulching for your locality, see Report on Evergreens from the States.)

FERTILIZING

If the evergreens are growing steadily, and if the soil is deep and fertile, an occasional feeding every 2 or 3 years may be all that is required to main­tain steady growth. In fertilizing, as in all phases of gardening, the judgment of the gardener must be exercised. When working with nature there can be no set rules; one is dealing with living material, and the inherent health of the individual plant and its growing conditions must dictate the amount of feeding required.

When the evergreens fail to make a vigorous growth, then fertilizing is essential. The kind of fertilizer to apply depends on whether the plants are acid-loving or if they prefer a soil that is alkaline.

Generally speaking, the narrow-leaved types like ground that is not as acid as that required by most of the broad-leaved kinds; these narrow-leaved types are benefited by the use of a commercial fertilizer such as a 10-8-6, a 5-5-5, or a 5-10-5; in fact, this is true of most of the plants which belong to this group. In the formula, the first number refers to the amount of nitrogen; the second phosphorus; and the third potash. All three of these elements are essential to plant life. In the northern United States the fertilizer is applied in March or April, and again in late August.

A fertilizer with a high nitrogen content is especially good for evergreens, since in addition to promoting their growth it tends to brighten their color. For small specimens the fertilizer can be spread over the surface of the ground as far as the outer spread of the branches, but care must be taken not to allow it to touch the branches or the trunks. Over an area which measures 10 x 10 feet, the correct amount to use is 2 pounds of organic fertilizer or ½ to ¾ of a pound of the chemical fertilizer. If the soil is fer­tile, and if growing conditions are favorable, the amount of feeding can be reduced. In any case it is important to follow the manufacturer's directions.

To fertilize larger trees the most efficacious method to follow is to bore holes about 2 inches in diameter and 12 to 18 inches deep. These holes are made with an iron bar, and they are spaced 18 inches apart around the outer spread of the branches, the total amount of fertilizer used varies from 2 to 4 pounds maximum per inch of the diameter of the trunk, unless specifically advised to use more. The diameter of the trees is measured about 5 feet above the ground. However, if the specimen is a small one, there is very little difference in the diameter from the base to about 4 or 5 feet in height, therefore in such instances the diameter can be taken at the base of the trunk.

When you have determined the amount of fertilizer needed, then evenly distribute it in each hole. If the trees are large, in order to accommodate the fertilizer, additional holes can be bored both beyond the outer spread of the trees and inside their spread. However, one must be careful not to make the holes closer to the trunk than about halfway between the trunk and the outer spread of the branches. It is a good idea to keep the fertilizer at least 3 or 4 inches below sod level, otherwise the grass will grow in tufts over the fertilized area and will spoil the even appearance of the lawn. A mulch of well-rotted cow manure 3 or 4 inches deep applied in late August is one of the best fertilizers that can be given to the narrow-leaved (needle) species. If this is used, then in the spring shake out the straw from the manure and rake any residue of the manure into the top inch or two of the soil.

Most of the broad-leaved evergreens require an acid soil. Cottonseed meal, soybean meal, or one of the acid fertilizers on the market that is espe­cially compounded for broad-leaved evergreens is excellent. Each spring one of these fertilizers spread evenly around the plants will give them a good boost; 4 or 6 weeks after the first feeding, a second application can be given to any of the evergreens that are backward.

A chlorotic condition can be recognized by the foliage turning yellow, variegated, or in some instances white. This paling of the leaves is brought about by a lack of chlorophyll—a cellular pigment that gives plants their green color. Chlorosis can occur from any one of various causes, such as poor drainage which results in root damage, impurities in soil and air, in­adequate or excessive amounts of certain soil elements, disease or insect pests, or temperatures that are too low. In the case of plants that require acidity, a common cause of this condition is a soil that is too alkaline; soil can also be too acid and cause the foliage to turn yellow. Sulfur applied at the rate of 1 pound to 100 square feet will increase acidity, the amount varies depending on the soil. More sulfur can be used in clay than in sandy soil. In combating this trouble a real help is to use a preparation of chelated iron. The iron in alkaline soils is not absorbed by acid-loving plants in sufficient amounts. One of these preparations sold under the trade name of Sequestrene is splendid. It is easily sprinkled on the leaves with a water­ing can, or it can be applied to the soil; just be sure to follow the instruc­tions on the container. If the application of Sequestrene does not improve the yellowing of the leaves in a week or two, then it is advisable to consult your Department of Agriculture County agent.

Evergreen trees and shrubs retain their foliage throughout the year, thus differing from deciduous trees and shrubs, which shed their leaves in the fall and have a definite dormant period. However, evergreens also lose some of their leaves at varying intervals; but their lovely green effect always remains intact; even though their growth is not active during the winter their foliage continues to function. We have all noticed the partial brown­ing of Pines; if the trees are healthy this browning need cause no concern, since it is only Nature's way of eliminating leaves that are no longer of use. The time these old needles fall varies widely with the different kinds of ever­greens; it may take place annually or it may not occur for years. Some­times it is influenced by weather and growing conditions. Plants that are overcrowded lack the proper light and circulation of air, with the result that the inner leaves on the branches usually turn brown. This is strikingly noticeable with Junipers, Arbor-vitae, and False-Cypress. Dry weather in summer, and high, drying winds in winter can also bring about this con­dition. The shedding of needles may be partly controlled if the ground is covered with a mulch, which helps to retain soil moisture.

WINTER PROTECTION

Various factors enter into the cause of winter injury. An insufficient supply of moisture in the soil is often responsible for winter loss. When the ground is frozen hard, evergreens are not able to draw from it the needed moisture to compensate for the amount of water lost through transpiration. Unless the rainfall has been plentiful during the autumn, make sure that the planting is given at least three heavy soakings before frost arrives; this will carry them through the cold months with greater safety. Snow damage is ruthless—valuable branches are often broken by its weight—and we must do everything possible to prevent this from occurring. Brush off the snow from the plants promptly with a broom, but if it freezes do not at­tempt to touch it until the ice thaws. Twigs and branches that are encased with ice are too brittle to handle safely. Snow in February and March is particularly injurious to evergreens because the increased warmth of the sun on the snow often causes the foliage to burn.

Smaller specimens can sometimes be shielded from the ravages of the winter with tents. These tents are made of lath, burlap, canvas, or some other material, and are supported by stakes. Frequently entire bushes are surrounded with burlap or canvas; when this is done care must be taken to leave enough space around the plants to allow a free circulation of air. Evergreen boughs driven into the ground around small bushes also give good protection. In some instances the protection may simply consist of a mulch about 3 inches deep of manure, straw, leaves, or compost. Various broad-leaved evergreens prefer a mulch of peat moss 1 inch thick or 2 or 3 inches of oak leaves weighted down with twigs, either of these is excel­lent for plants in this group. In cold climates it is always advisable to give winter protection to evergreens for the first 2 years after planting.

A newer way of giving protection is to spray the plants with a plastic such as Wilt-Pruf. Wilt-Pruf lessens the water loss—if water loss can be retarded in winter less damage occurs. This should be applied to the branches and the upper surfaces of the leaves, thus checking loss of mois­ture through transpiration. You can mix Wilt-Pruf yourself according to the manufacturer's directions, or buy it already mixed and ready to use in refillable containers; this is a more expensive way to purchase it, but it is very convenient and saves the trouble of mixing and using the sprayer. If the sprayer is used, it must be thoroughly cleansed immediately after use. The effect of the spray lasts for about a month. If it is applied in late winter, the plants will be protected during their most vulnerable period. Two or more applications can be given during the course of the winter, and naturally this will give even more efficacious protection. Wilt-Pruf should not be applied if the temperature is below freezing.

Whenever it is possible to use a plastic spray and a mulch it is, of course, more desirable to restrict the protection to this combination. One of the chief assets of evergreens is the welcome color they provide to the winter garden, and it is a pity to mar this pleasure with unsightly kinds of protection.

In cold climates and in windswept places it is sometimes necessary to have a windbreak to give shelter from the prevailing winds. A line of ever­green trees planted approximately 6 or 7 feet apart will provide one of the best foils against the bitter winds and snowstorms of winter. Where there are wide sweeps of unbroken land, one or more additional rows of stout growing trees will be required for adequate protection.

There are a number of trees that are well adapted for this important service. It is advisable to consult your nurseryman as to the kinds best suited to your particular locality, soil conditions, and exposure. Generally speak­ing, some of the most desirable species for the purpose are Spruces, Hem­locks, Douglas-Fir, Balsam Fir, Arbor-vitae, and Red Cedar. If a lower windbreak is all that is needed, one of the Yews will be the solution, such as Taxus cuspidata and T. cuspidata nana. Two very popular types are T. media Hicksii and T. media Hatfieldii, and they are excellent for this use, provided they are kept within bounds by pruning.

Artificial windbreaks may be made of straw mats, canvas, or burlap; they are supported by stout stakes driven into the ground and are reinforced with heavy wire run from stake to stake. If there is no alternative, corn­stalks can provide the shelter, but these are apt to attract rodents, there­fore they are the least desirable. Sometimes a fence is used to break the force of the winds; if one of the kinds that contributes to the aesthetic value is selected, as for instance a wood woven fence, it will not only give pro­tection but may also provide a background for an attractive

Are You Ready To Move Onto The Next Lesson? Click Here...