CHAPTER  VI
 

                        Soils and Mulching.



If one could choose one's own soil for the cultivation of  trees and shrubs

generally, it would be a deep loam  of a light rather than a heavy nature,

and free from all calcareous substances.   Such a soil is easily worked and

would support the most  varied collection of species, including the great

family of Ericacecz, whose  members give so much beauty to gardens.

The species  found on limestone are numerous,  but to very few of them

is  lime absolutely essential.   For some,  such  as  certain  species  of

clematis and juniper, and  such conifers as Abies Pinsapo, it is advisable

to add lime to soil  deficient in it;  but generally one is led to the  belief

that trees and shrubs inhabit limestone regions not so  much from choice

as from necessity.   The beech, for instance, or the whitebeam, commonly

found wild on  the limestone, thrive just as well  apparently where it is

absent.   Peat-lovers, again, are by no means incapable of thriving on a

loamy soil.  The heath family, including such genera  as Calluna, Erica,

Rhododendron,  Azalea,  Dabxcia, and Pieris, are usually found wild on

peaty soil, but everyone of  them will succeed in loam of a sandy nature

and free from lime, especially if decayed leaves be added  to it.

   The great value of decayed leaves—the "leaf-soil" of the  gardener—

as an ingredient  in soil of  any type is not yet generally appreciated,

although one hopes the old wasteful practice  of burning fallen leaves,

after raking them together  in  early winter, has in a great measure ceased.

Every garden of  any pretensions should have its  " leaf-heap," where the

gathered  leaves may be carted and  turned over  two  or three  times

annually as occasion offers.  In two years a black humus is formed which

no tree or shrub, so far as I know, will object to, but which, on the other

hand, the roots of almost  everyone will  avidly seize on.  For  delicate

rooting shrubs like the Ericacea, eucryphias, stewartias, the more  delicate

magnolias, Chilean and  New Zealand shrubs generally, it is particularly

useful, and makes an admirable substitute for peat  in  many cases.  As a

mulching  for evergreens, a layer of leaves has much to recommend it, and

in the  case  of those  with  low  branches like rhododendrons, which

prevent  the leaves  being blown away, it is a  good  plan  in  autumn  to

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