Starting a Garden : Soil Improvement
It is always a daunting task when starting a garden site from new when it consists of little but rough ground and the builder’s debris. It is always to be hoped that the good topremoved during excavations have been placed on one side for subsequent redistribution. In any case, levelling the ground and carrying out any necessary is very much the order of the day.
Many gardens have more than one kind of soil; I, for example, have gravel quite near the surface at the top of my garden while lower down the slope l have heavy clay. In the case of light sandy or gravelly soils with poor moisture retention properties, it will always pay to dig in such humus-forming material as, peat, farmyard manure, leaf mould, spent hops or straw, to improve their structure.
Slow-acting fertilisers such as bonemeal and hoof and horn will also do a lot of good. A cheap and easily used soil-testing outfit will tell you whether your soil is acid or alkaline, over-acidity being corrected by application of lime.
The most common soil type is clay, which, to say the least, can be difficult to work. But there are few better growing mediums than a clay soil which has been worked on and improved over a matter of years. With clay soilsis of paramount importance, for in the nature of things they are extremely retentive of moisture, the individual soil particles being very small indeed.
The humus-forming materials which I have just mentioned in connection with light sandy soils, are just as useful for clay soils for the opposite reason – namely that they break up the close-packed soil particles and so allow excess moisture to drain freely to lower levels. One of the key factors in the successful mastery of clay soils is timing your cultivations correctly. Working them in wet weather for instance is a mistake, for the compaction which results can do enormous harm. On the other hand, digging during good weather in autumn so that the surface can be left rough for the alternating frosts and rains of winter to break down, is just about the ideal. Where ericaceous or other lime-hating plants (such as ericas, rhododendrons, azaleas, camellias and magnolias) are not going to be grown, dressing with lime or gypsum will also help to improve the soil – and then it will grow almost anything. But it is a long-term business.
Perhaps this is a good time to emphasise that it is far better to grow those plants suited to your type of soil than to do things the other way round and try to make the soil suit the plants’ requirements. I am referring now, of course, to fundamental things like having the wrong kind of soil or the wrong aspect, and not to soil improvement or the removal of branches from trees to let in more light.
You can nowadays grow lime-hating plants in calcareous soil by treating the latter with iron sequestrene, to release the iron previously unavailable to the plants, but the necessity for further applications at intervals and the resulting expense does not make this a practical proposition for most of us if large numbers of plants are involved. It is, however, a very useful technique if you wish to grow a few lime-hating plants of special interest in calcareous soil.
At this early stage too, it is essential to determine if the natural drainage is sufficient to cope with all likely weather conditions. If there is any reason to doubt this it is a good idea to dig two to three foot deep holes in several parts of the garden and then see if these hold water after heavy rain. Land which is low-lying or very heavy is liable to suffer from bad drainage and the water logging associated with this will result in the roots of plants dying and often the complete loss of the plants.
Drainpipes, three inches in diameter, put 2 feet underground and leading to a suitable outfall, provide the best remedy, but a trench partly filled with rubble, covered first with a layer of turf and then with soil to surface level, is usually quite effective, but a good lawn can be made quite quickly by this means.