36 ALPINE PLANTS 
available, a number of the daintiest varieties of asplenium, 
such as A. trichomanes, A. ruta-muraria, A. adiantum- 
nigrum, are particularly appropriate, whilst crested 
Scolopendiums in infinite variety of tasselled ends and 
crimped edges, are full of beauty and interest. In the 
drier parts the oak-leaved Polypodium and also Poly- 
podium cambricum, will produce charming fronds. 
At the base of a wall, especially if a peat bed and some 
water can be provided, the royal fern Osmunda regalis, 
and its sister, Osmunda palustris, will give an air of richness 
to the wall garden, and so also will colonies of hardy 
Cyclamen, Erythroniums, Dodecatheons, Orchis foliosa, San- 
guinaria canadensis, and the Colchicums, add charm and 
beauty to the scene. 
During periods of severe drought, careful attention 
must be paid to the watering of a wall garden, and that 
is one point over which many garden owners go wrong. 
Too often a hose-pipe connected with a tap-main is trained 
on the face of the wall, and the water ejected with such 
force that much of the soil is washed from between the 
stones, laying bare many of the surface roots of the plants, 
and very probably dislodging entirely any young seedlings 
that may be germinating. The face of the wall streams 
with water, the foliage of the plants drips, and all looks 
well, but the whole effort has totally failed to soak the 
soil at the back, where the main roots of the plants are. 
Where a wall is sunk below the level of the ground and 
leans against a vast body of earth, there is not much need 
for watering, even in very dry weather, except in such 
instances as where the soil is a network of roots of big 
