Drainage is an important matter in the garden in every section of it. Neither paths,nor flower beds can be made satisfactorily unless the ground has already been well drained.
Let us consider what to do with the garden where the ground appears to be waterlogged. If, for example, when a hole about fifteen inches each way is dug and left for a day or two, water collects and remains stationary in the bottom of the hole, the ground must be provided with extra drainage. Ordinary deep digging will not be sufficient to carry off the surplus moisture. The time to improve the drainage in this way is, of course, before any other garden construction is begun.
Three-inch pipes inserted one foot below the surface and laid in parallel lines with about fifteen feet between each line, are sometimes sufficient to effect good drainage. Occasionally, it may be necessary to add some smaller drains, two to three inches in diameter, and to carry them into the larger drains at an angle of sixty degrees every fifteen feet. This means that it will be necessary to excavate trenches say about fifteen inches deep and fifteen feet apart, and to join them herring-bone fashion, allowing a slight drop in the bottom of the trench towards one end of the plot. The surplus water will be carried to this end and some special arrangements must be made to carry it away either into the main drains or into an artificial sump. As a matter of fact, it is rarely necessary in the little garden to make any such drains as described, and even in a garden which appears at first sight to be waterlogged, it will probably be found sufficient to excavate one or two trenches and to fill the bottom of each with all kinds of rough material, such as tins (beaten flat), broken crocks, bundles of brush wood or gorse, and rough clinker.