Redesigning The Lawn Drainage

A decision we all have to make when contemplating making a new lawn is whether to use seed or turf. One would always recommend seeding, whenever possible, for it costs about a quarter the money that buying turf does, and the preparatory work for both is just the same.

Of course, if the area to be grassed down is not very large and there are children in the family whom it would he difficult to keep off seeded ground, then turf has obvious advantages. If permanent garden features are considered, it is very important indeed, that deficiencies in drainage should be corrected early on.

This is certainly true of lawns, for a grass area which holds an excessive amount of water is nothing but a worry in our climate. The grass will be weak and, moss, lichen and other weeds will be encouraged.

Mowing is often delayed because of the state of the ground and in really wet spells it becomes a mud patch if walked upon. Heavy clay soils with a sub-soil of pure clay are the ones that mostly need such attention.

How one treats the ground depends largely on the area involved. lf the area is small it is a good idea to remove all the topsoil and put down a layer of clinker, broken bricks, stones or similar material on top of the subsoil to a depth of several inches. This is then rammed down firmly, and covered with another layer of weathered coarse ashes, or other bulky material which will effectively stop the topsoil filtering through the drainage material when it is returned.

Another way is, to dig a soak-away about 2ft. deep and 2ft. across, in the lower part of the area and to fill this with rubble, broken bricks, stones, clinker and so on. Top them up with smaller stones and finish off with at least 4 inches of topsoil. Finally, the most expensive and complicated method of drainage, suitable for large areas, is to lay 3 inch earthenware drainpipes in 2 feet deep trenches made with a fall of l in 100 and leading to a deep rubble filled soak-away.

The pipes should rest on a bed of small stones or clinker and be covered with brushwood or straw and then clinker to prevent the soil, from seeping into the pipes. A more complex system of drainage is to lay a central drain with subsidiary drains leading to it, at intervals of 10 to 40 feet, from each side like the herring bone fashion, with the central pipe having a diameter of 4 inches and the subsidiary pipes with 3 inches. But it is not normally necessary to go to such lengths.