188 



HORTICULTURE. 



Enclosure naturally on the surface should be noted, as from these 

 ^X" 118 ' a P rett y correct opinion may be formed of the qualities 

 *"~ Y " W ' of the soil. The subsoil should also be examined. If 

 this be radically bad, such as an iron-till mixed with 

 gravel, no draining, trenching, or manuring will ever 

 prove an effectual remedy ; if, on the contrary, the 

 subsoil be tolerably good, the surface may be greatly 

 meliorated by these means. In every garden, two 

 varieties of soil are wanted, a strong and a light one, 

 or, in other words, a clayey loam and a sandy loam, 

 different plants requiring these respective kinds. For 

 the general soil, a loam of middling quality, but par- 

 taking rather of the sandy than the clayey, is account- 

 ed the best. 



Enclosure Walls. 



Walfa. 40. When the situation is fixed on, the next con- 



sideration is the enclosing with walls. Supposing a 

 garden to be about an acre in extent, and the ground 

 sloping gently to the south, the rule is, that the north 

 wall may be 14 feet high ; the south wall, 10; and the 

 other walls, about 12. In a larger garden, containing 

 perhaps four acres, the north wall is sometimes raised 

 IS feet high; the side walls, or those on the east and 

 west, 15 ; and the south wall, not more than 12. On 

 a dead level the north wall is generally made 16 feet 

 high ; the east and west walls 13^ ; and the south wall, 

 11. It may be observed, that walls higher than 12, 

 or at most 14 feet, are necessary only for pear-trees; 

 peach, nectarines, apricot and plum-trees seldom re- 

 quiring more than 12 feet. It may also be right to no- 

 tice, that the terms north and south wall are here used 

 to denote the north and south sides of a square or pa- 

 rallelogram ; but that, in speaking of wall fruit, if it be 

 said that peach or fig trees require a south wall, this 

 must be understood to mean a wall with a south aspect, 

 or what is in reality the north wall of the garden. 

 There are two motives therefore for raising this wall 

 some feet higher than the others ; first, sheltering the 

 garden from the northern blast; and, in the next place, 

 the procuring of ample space for training the finer 

 kinds of fruit-trees on the south side of the wall, or 

 best aspect of the garden. Under the denomination of 

 finer kinds of fruit-trees are to be understood not only 

 peaches, nectarines, apricots and plums, but some of 

 the French pears, such as the chaumontel, colmart, and 

 crassane. Many gardeners are of opinion that the best 

 aspect for a fruit wall in this country is about one point 

 to the eastward of south ; such walls enjoying the be- 

 nefit of the morning sun, and being turned a little from 

 the violent west and south west winds. South-east is, 

 for the same reasons, accounted by many a better as- 

 pect than south-west. The south. west and west walls 

 are assigned to fruits which do not require so much 

 heat to ripen them as is necessary to those above men- 

 tioned ; such are cherries, many kinds of pears, and ap- 

 ples. The north walls are appropriated to apples and 

 pears for baking, plums and morella cherries for pre- 

 serving ; and a few may-duke cherry, white currant 

 and gooseberry trees; are trained against these walls 

 with the view of their affording a late crop. 



Bricks, it is generally allowed, are the best material 

 of which to construct the walls. The foundation and 

 basement are often made of common building sand- 

 stone, while the superstructure is brick ; and some- 

 times the back part of the wall is of sandstone, and the 

 front only of brick. Sandstone which rises in flags is 

 the best substitute for bricks. Both kinds of materials 

 admit of the branches of the trees being nailed-in regu- 

 larly, and without difficulty. Where the walls are 



of common rubble building, a trellis of spars is some- 

 times placed against them, and to this trellis the 

 branches are tied with osier-twigs or rope-yarn. This 

 is regarded as a very good plan ; but the expence is 

 considerable, as, to prevent the lodging of insects, the 

 trellis must be smooth and painted. The trees thus- 

 enjoy the shelter and reflected heat of the wall, without 

 being injured by its dampness in rainy weather ; and 

 as the wall is not injured by the driving and drawing 

 of nails, there are fewer lurking-places for the wood- 

 louse and the snail. The rails of the trellis are made 

 closer or wider according to the nature of the tree to be 

 trained against it. In a few instances in Scotland, 

 walls have been built of different kinds of re/tinstone, 

 chiefly greenstone and basalt. These minerals, on ac- 

 count of their almost black colour, are calculated to ab- 

 sorb and retain more heat than stones of a light hue : 

 but it is to be considered that it is not the heat retained 

 by the wall which benefits the tree, so much as the heat 

 reflected from the wall. The proposal of painting walls 

 black, is, on the same principle, not admissible. It 

 may here be of some importance to remark, particular- 

 ly as applicable to Scotland, that in building brick 

 walls, bricklayers only should be employed ; stone-ma- 

 sons working as awkwardly and clumsily with bricks,, 

 as bricklayers would do with masses of whinstone. 



As the walls of a garden form one of the principal 

 sources of expence, it is proper, before proceeding to 

 build, to ascertain correctly the average level of the 

 borders, if the ground be unequal, so as to suit the 

 depth of the foundation to it. If the inequalities be 

 considerable, both walls and borders are made to sink 

 and rise, so as to humour them. Declivities in a gar. 

 den are not unpleasing; and when they happen to 

 slope to the south or east, they afford the earliest crop 

 of different legumes, such as peas or beans. Some im- 

 provers have constructed a series of low flat arches as 

 the basement of the wall, these arches having their tops 

 on a level with the surface of the borders ; the piers 

 left are from two to four feet broad, according as the 

 foundation is firm or otherwise. The advantage con- 

 sists not merely in saving much building, but in per. 

 mitting the roots of the wall trees, which are planted 

 opposite to the arches, to extend themselves in every 

 direction, and draw nourishment from the soil on both 

 sides of the wall. In some places projecting stone but- 

 tresses are set at intervals in the walls, in order to 

 strengthen them, and to break the force of the winds 

 when sweeping along. But to this latter purpose they 

 contribute little : temporary screens of reed, projecting 

 at right-angles from the wall, and removed after the 

 blossoming season, when the chief danger is over, are 

 thought better : and if any sort of strengthening co- 

 lumns or piers be necessary, they can be built so as to 

 project only on the outside of the wall. In this coun- 

 try, walls are generally made of the thickness only of 

 three bricks laid side by side, or somewhat more than 

 a foot ; and to such walls in exposed situations, but- 

 tresses may be very proper. When the walls are in- 

 tended to be high, indeed, they are commonly made 

 sixteen inches thick for a few feet above the basement, 

 and then gradually reduced to twelve or thirteen. The 

 basement, whether of brick or stone, is always about 

 six inches thicker than the lower part of the wall. 



Walls have sometimes been built with curves ; and 

 in perfectly calm weather, the trees in these curves 

 must receive more heat than on a straight wall ; but 

 it ,is found that in windy weather they suffer much 

 more ; and that even when there is only a slight air of 

 wind, a draught is produced around the trees, render. 



Enclosure 

 Walls. 



