30 HARDY PERENNIALS 
should proceed when the ground is excessively wet. 
This applies to all soils but more especially to those 
that are heavy and close in texture. Never dig in 
the frosted crust of soil, and certainly snow must 
never be buried. If a garden is on water-logged 
ground something must be done to improve drainage. 
The laying of an elaborate system of pipe drains 
will not be dealt with here, its costliness preventing 
the average flower gardener adopting it ; but even 
extremely wet gardens may generally be vastly 
improved by excavating a deep pit, or cutting a 
ditch at the lowest end and running a rough drain 
toward it by burying a seam of brick rubble and 
stones two or three feet below the surface. 
