[ 49 ]ARNOLDIA ~ -E IA publication ofTHE ARNOLD ARBORETUM OF HARVARD UNIVERSITYJamaica Plain, Massachusetts 02130VOLUME 29 AUGUST 29, 196J NUMBER HESPALIERED PLANTSTHE old fashioned art of growing espaliered plants is very definitely coming-~- back into favor again. Only recently it seems this type of pruning wasfrowned upon, for it was too time-consuming. However, the gardener with moreand more time on his hands often wants to produce something out of the ordi-nary, especially in smaller gardens-something that shows off a blank space ona wall or fence to good advantage. Because of this desire, more gardeners arebecoming interested in learning how espaliered plants can be grown.When the plot of ground is narrow, against a wall or fence, this method ofgrowing shrubs and trees is certainly decorative and conserves space. Vines growtoo fast for the low wall, and often require much care to keep them in good form.Take the space in front of a garage with a foot or so of ground, but a wall ten tofifteen feet high-this is the ideal place where espaliered plants come into theirown. Certainly, they do not grow so vigorously that they hide the wall, but theforms into which the plants can be trained augment the interest of the plantingmaterially.We have such a wall along the low building that is our cold storage house atthe Arnold Arboretum. The wall is made of painted cement blocks, with abouteighteen inches of soil in front of it and bordered by a paved road. Obviously,it is impossible to plant shrubs in this small area. Espaliered plants have provenmost interesting here, not only because the foliage breaks the monotony of thewall but also because of the different designs into which these various plantshave been trained.In selecting plants for this purpose, certain ones have proved themselves moreamenable than others. Japanese yew, firethorn, forsythia, flowering dogwood,rockspray (Cotoneaster horisontalis), mock-orange, flowering crabapples and ofcourse the fruits like apple, pear and peach-all are worthy subjects for trial.Beside the fruits, best grown on dwarfing understock, Pyracantha species haveproved most popular and suitable to this type of pruning.~~o) ]One should study the wall space available, the method by which the plantsare to be held firmly to the wall, and finally the design or form into which theplants will be trained. It is most important to have all this figured out in ad-vance. Young plants three or four feet tall are usually the best ones to startwith, for the root system of these need not be reduced to fit into the availablespace, and one can begin more easily with young and pliable twigs to create thedesign which has been selected.The designs are of several major patterns. A fan shape is probably the easiestwith three or four straight branches emanating from the base. The Japanese yewis especially satisfactory for this. Any yew, but preferably an upright growingvariety, can be planted and reduced to three or four main branches arranged ina fan shape. It should be important to select a fruiting plant (not a male orstaminate plant which never bears fruit) for when the small red fruits cover thesebranches m the fall the plant has a unique interest. Also this plant can be es-paliered against a cedar or chestnut sapling fence, with excellent results. Prun-ing of this particular plant is merely done in the form of snipping or shearing tokeep the four main branches no wider than four to six inches. If plenty of spaceis available and if one design is good, additional leaders can be allowed to formafter the original main branches have grown four or five feet high.The horticulturists of the past centuries have done interesting things with es-paliered fruit trees. Mount Vernon, Virginia is only one place of many in thiscountry where espaliered fruits can still be seen, but in Europe the art is stillwidely practiced. Some plants have been trained in a horizontal cordon- merelya low trunk a few inches tall and then a horizontal branch on either side. Start-ing with this simple design the ramifications are many. The single upright trunkof this can be allowed to grow vertically with additional horizontal branches al-lowed. Or the simple horizontal branches can be trained to the vertical afterthey have been allowed to grow ~n the horizontal for a certain length. Also thepopular gridiron form is another often used.Another interesting method is to develop from the original simple horizontalcordon a series of evenly spaced upright branches. Even more difficult for theindividual who wants to try his hand at this, is to start with something likeforsythia - because it is easily pliable and grows fast. Three or four main branchescould be allowed, but each trained in a pleasingly larger and larger arc. Heretoo, the side shoots should be kept trimmed or pinched so that they will all beshort. In the case of forsythia, it is essential that as much pruning or shearingas possible be done while the plant is actively growing before the end of Juneso that the flower buds will have plenty of time to form for next year’s bloom.The rockspray (Cotoneaster horizontalis) produces flat sprays even when theserest normally on the ground. When advantage is taken of this unique method ofgrowth by training them against the wall, a very interesting design results.It is probably best to try to grow espaliered plants on walls facing the northPLATE XIIIA few of the designs which are used in growing espaliers.[552 ]or east. South or west facing walls may be subject to absorbing too much heaton unusually warm winter days, so that some burning might result. Holes canbe bored into the concrete, stone or wood walls and large brass or copper hooksinserted to hold the twigs rigidly in place. Preferably these should be of lead,for this material will bend slightly with the increase of branch girth, whereasstiff brass or copper hooks, if not large enough, can completely girdle and eventu-ally kill a branch.Bending or turning the young twigs is a technique requiring minute care forthe twigs must not be broken. Also they must be held rigidly in place. This typeof training is best done in the spring while the twigs are young and flexible.Pruning or "touching up" with the shears is a frequent operation, the objectbeing to prevent unwanted twigs from growing and to allow desired twigs togrow just far enough so they can be forced into the chosen pattern. Pruningshould be done only when the design or form is thoroughly kept in