It has been stated that plants do not grow naturally in the soil best
suited for them, and that the reason why many plants are found in
peculiar places is not at all because they prefer them, but because they
alone are capable of existing there, or because they take refuge there
from the inroads of stouter neighbours who would destroy them or crowd
them out. There are, as every gardener knows, numerous plants that
succeed equally well in widely different soils, and a soil which may be
suitable for a plant in one place, may prove totally unsuited in
another. Hence it is why we find one gardener recommending one kind of
soil, and another a different one, for the same plant, both answering
equally well because of other conditions fitting better with each soil.
This helps us to understand how it is that many garden subjects grow
much better when planted in composts often quite different from those
the plants are found in when wild. Few plants have a particular
predilection for soil, and some have what we may call the power to adapt
themselves to conditions often widely different.

In Cactuses we have a family of plants for which special conditions are
necessary; and, as regards soil, whether we are guided by nature or by
gardening experience, we are led to conclude that almost all of them
thrive only when planted in one kind, that soil being principally loam.
Plants which are limited in nature to sandy, sun-scorched plains or the
glaring sides of rocky hills and mountains, where scarcely any other
form of vegetation can exist, are not likely to require much decayed
vegetable humus, but must obtain their food from inorganic substances,
such as loam, sand, or lime. So it is with them when grown in our
houses. They are healthiest and longest-lived when planted in a loamy
soil; and although they may be grown fairly well for a time when placed
in a compost of loam and leaf mould, or loam and peat, yet the growth
they make is generally too sappy and weak; it is simply fat without