bed by the moving.

[Illustration: Good rock garden planting. Each of the principal species
has a soil pocket to itself. Note the effective background and irregular
crevices]

Boulders may run up to several tons in weight. Where none is readily
obtainable, one can be simulated by ingeniously combining a few small
ones and concealing the joints by the planting of such things as
stonecrops in earth--which, save in rare cases of sheer necessity, is
always used in the construction of a rock garden in place of mortar.

If the site is level, the next step is to change all that--first on
paper. Unless the lay of the land is all right at the outset, the
configuration of the rock garden must not depend wholly upon the
upbuilding; there must be some excavations, but no depressions deep
enough to catch and hold water just where you will want to walk.

Aside from the path levels, building begins with the rocks, not with the
soil. This is a highly important point. Place the boulders first; they
are the big effects. Aside from that, the heaviest work will be out of
the way. Then start in with the outlining base rocks. These should be
placed with the largest surface to the ground and should vary in size.
It is not essential that the lowest rocks should be slightly buried in
the ground, but that course is preferable.

When the paths and outer margins have been thus defined, scatter more
rocks over the intervening surface, placing them fairly thick but not
close together. Next, fill in with soil, packing it firmly and ramming
it hard into every crevice. If it fits in with the day's work, it is not
a bad plan to water the rock work well in order to pack the soil, and
when resuming the labor on the morrow, to add more soil, well pressed
down, before proceeding with the second layer of rock.

This second layer should have the rocks placed with the front edge
slightly back from that of the lower row in order to form a slope,
though an occasional overhang may be fashioned if required for a certain
plant known to abhor a drip from above. The construction then proceeds
as before, until the desired height is reached. The height is entirely
arbitrary, but some points should be at least as high as the line of
vision, as one of the great advantages of a rock garden is the pleasure
of enjoying some of the typical rock plants without stooping. The rocks
used as fillers should overlap here and there to give strength, but care
must be taken to c