40 
HERBACEOUS GARDEN 
quickly freeze in severe weather and so rot 
and kill them. 
Plants on a dry soil will stand many more 
degrees of frost than those on cold clay, owing 
to the porosity, and consequent freedom from 
damp, of the soil. Undrained clay will often 
only grow the coarsest and rankest of per- 
ennials, until thoroughly worked and improved. 
A border raised some twelve inches above 
the surrounding ground, with some stones or 
clinkers as a foundation and edging, is an ex- 
cellent plan ; and even Eremuri will survive the 
English climate, if planted on such a border, 
as well as snapdragons and other half-hardy 
plants. The finest snapdragons seen this last 
wet summer had been thrown out on to a heap 
of rubbish, chiefly pea-sticks. They flowered 
magnificently, owing entirely to the excellent 
drainage and consequent dryness of their 
position. Manure placed in contact with the 
roots of a plant is apt, in wet soils, to rot 
them, and should be placed lower down. 
Mortar-rubble is most useful to lighten a 
clay soil, which should be well trenched, two 
or three spits deep (a spit being the depth of 
the spade), and, failing mortar-rubble, ashes or 
leaf-mould or burned clay may be used to 
lighten it. In trenching (for the benefit of 
