38 



GARDEl^ERS' CHROMCLE 



The Bog Garden 



ARTHUR SMITH 



CL)-MrARATl\i-:LY lew people are aware o'f the 

 multitude of charming" plants which make their 

 home upon j)eaty bogs. As it is useless attempting 

 to make inirely bog plants to grow, or at all events really 

 thrive anywhere else, we must, if we desire their en- 

 joyable company, create an environmnt suitable for them. 



Superficially considered, there may not appear much 

 difference between the requisities for a bog garden and 

 a water garden. There is, however, a specific distinction 

 which requires to be emphasized i}efore we can thoroughly 

 understand the principles underlying the construction of 

 artificial Ixjgs. 



Many plants known as aquatics, or semi-aquatics, will 

 grow in a bog, but no true bog plant will thrive as an 

 aquatic. If a natural bog is examined, it will invariably 

 be found to be composed of spha.gnum moss and a black 

 peaty substance, floating in water more or less deep, al- 

 though perhaps touching the bottom at the edges, and a 

 portion of this material on, or in, which the plants are 

 growing is always raised above the level of the water. 

 Thus, while part of the roots of some of the plants may 

 reach the water below, nearly all of the plant itself is 

 growing above, not in, the water, and if the water rises 

 then the medium in which the plant rests, rises with it. 

 Therefore while the bog plant is always living under con- 

 ditions of perennial and abundant moisture it is never 

 actually in the water. 



In a swani]) there is always more or less drainage in 

 the sense that although water may be continually running 

 in, it is also continually running out, and the swampy 

 medium is closely in connection with the soil below. In 

 a true bog drainage is practically non-existent, and there 

 is invariably an underlying stratum impervious to water. 

 Bogs are generally found in holes unconnected with run- 

 ning water, ad they very frequently are found on moun- 

 tains and alpine situations : in fact there are quite a num- 

 ber of alpine plants which are denizens of bogs. 



From the fact that water does not flow or soak through 

 a bog. bog-water is always more or less acid and dark- 

 colored. This is a condition which is peculiar to bogs 

 and which is not found in places where the w-ater is al- 

 ways moving forward, even if slowly, and it is suitable 

 to the existence and growth of certain fungi which are 

 necessary to the life of many Ixig plants. 



These fungi are really microscopic plants and they live 

 in association with the roots of other plants, digesting 

 their food, or at least most of it. for them. This asso- 

 ciation of root and fungus is technically known as my- 

 corrhiza, and in Nature, bog soils are known to have a 

 large number of mycorrhizal plants growing in them; 

 that is. plants which will not thrive without the existence 

 of their special root-fungus. It is worthy of note that 

 many trees, shrubs and other ])lants living on upland 

 soils, also exhibit mycorrliiza. There are two classes of 

 mycorrhiza, one which penetrates the cells of the roots, 

 known as endophytic, and the other known as ectophytic, 

 in which the fungus invests the root with a covering of 

 mycelium the threads merely coming into close contact 

 with the root cells without entering them. In Imth cases, 

 especially in the latter, the reason lor allowing as much 

 of the medium in which plants are growing to remain 

 on a plant's roots when transplanting is indicated, and 

 also explains the fact that there are many i>lants which 

 will never survive the 0[)eration of removal to another 

 ])lace unless their roots are kept covered with the moist 



medium in which they have previously spent their lives. 

 Actually, comparatively little is known of the delicate 

 and complex relationship between the mycorrhizal habit 

 of obtaining footl used by bog plants and the acidity of 

 bog water, hut exjjericnce has shown that such relation- 

 shi]) exists. 



Natural bogs have been many hundreds of years reach- 

 ing their present condition and their being where they 

 are presupiK)ses an underlying stratum impervious to 

 water, therefore in constructing an artificial bog a water- 

 tight bottom must first be secured. 



( )f primary importance is, of course, the position, and 

 w here there is an undrained area in a hollow, the problem 

 almost solves itself. In such a case all that is necessary 

 is to excavate the ground to a depth of not less than 

 two feet, to any extent available or that may be desired, 

 ])!ace a layer of puddled clay to make the basin surely 

 water-ti,ght and then put in the soil mixture as described 

 later on. Where there are no naturally suitable sites and 

 in dry situations a bog garden may be made by forming 

 a basin and lining it with concrete a foot thick over which 

 should be smeared an inch or two of puddled clay not 

 only for the purpose of making it absolutely water- 

 tight, but also to counteract the action of lime contained 

 in the concrete. 



The size and form of such garden may be varied at 

 discretion. While it is imixartant to secure informality, 

 as with all other natural gardens, one must guard against 

 the stiff, or regular, informality which sometimes places 

 the brand of artificiality over gardens -of this kind. A 

 visit to a natural bog, and the observing of its lines and 

 characteristics will be very helpful to those contemplating 

 the formation of a bog .garden which will be artificial, 

 but which it is desired at the same time to appear natural. 

 .Obviously tlie best material in the way of soil to use is 

 that from a natural bog taking everything as it comes, 

 with as much bog-water as possible, for which purpose 

 barrels are the host things to move it in. When this bog- 

 muck cannot be obtained a mixture may be made of leaf 

 mould, commercial peat, wood-earth scraped from the 

 surface, under oaks preferably, together with the twMgs 

 and leaves from the forest-fioor, so that the mixture as 

 a whole will form a spongy mass. 



irregularly-shaped mounds and ridges should be 

 formed rising a foot or more above the water level. This 

 not only gives a more natural and pleasing contour but 

 affords a greater planting surface from a given area, and 

 creates conditions for plants preferring to be more raised 

 above the water than others ; also plants can be better 

 dis]>layed than when the surface is entirely fiat. Rocks 

 to act as stepping stones may be placed at convenient in- 

 tervals to enable one to walk alx)Ut the lx)g, to see the 

 l)lants and ]jerform any work required connected with 

 them. 



\\ hen a piece of naturally swampy ground is chosen 

 for the site of a bo,g garden it will lie sure to have a crop 

 of more or less coarse, water-loving plants, such as Cat 

 Tails, Rushes. Sedges, and the like, growing on it. These 

 must first lie thoroughly eradicated nmt and branch, 

 otherwise they will only work harm .among and ultimately 

 kill out bog plants. 



A bog garden should not be formed in a jwsition likely 

 to Ijc affected liy storm-water, ]>rcfcrably it should be 

 where water sufficient to take care of evaporation only 

 sbmild rut/r or trickle into it. Effort should be made to 



