Coping With Dry Soils

Press, Volume CII, Issue 30211, 16 August 1963, Page 6

Coping With Dry Soils

One often hears a remark such as “I can’t grow anything in my garden in the summer—the ground is much too dry.” There are two possible reasons why this may be: one reason may be due to a soil pan. This may develop when cultivation is always shallow and only the top six inches of the soil is worked. Beneath this cultivated layer, the soil becomes compacted and hard, resulting in impeded drainage and rapid drying out in the summer of the top soil. Moisture cannot move up from the subsoil, and the roots of plants cannot penetrate the hard pan to the moisture below. Deep digging, as described in a recent article, will rectify this trouble.

The most common reason for a dry soil is the soil type, the soil is very sandy or gravelly While drying out in the summer can prove a serious handicap, a light soil has advantages. It is easy to work and rapid drainage allows it to be worked at almost any time. It also warms up quickly. Light soils are hungry tor organic matter and fertilisers are quickly lost from them. Heavy dressings of organic matter should be worked into the soil every year. The organic matter acts as a sponge, holding moisture and also chemical nutrients.

As it decomposes it releases nutrients. The organic matter should be supplemented

by regular small dressings of quick-acting fertilisers or more occasional applications of the slow-acting ones. Light soils are invariably acid, so regular applications of lime should be applied, at least to the vegetable garden. Once the ground begins to warm up in late spring mulches should be applied. These help to conserve the moisture in the soil by acting as insulators against evaporation of soil moisture. Materials that can be used are sawdust, leaf mould, compost, well-rotted manure, stack bottom or rotted straw; these can be worked into the soil the following winter and so increase the organic content. Weeds, if allowed to become established, compete with other plants for soil moisture. Keep the hoe going at all times, not only to control weeds but to maintain a fine tilth which, although it quickly dries out, acts as an insulator and reduces further moisture loss.

When deciding what to grow on a dry soil a little planning will help you to maintain a constant display and supply of vegetables. In the vegetable garden, plan for early maturing crops while there is still plenty of moisture in the soil. Vegetables in dry soils grow slowly and produce a crop that is tough and stringy. Ensure that salads, brassicas, and root crops mature before the soil dries out Many kinds of vegetables are today available in varie-

ties specially suited to the drier, warmer months of the year. The seeds of these should be sown so as to mature during this period. When laying down a lawn on a dry soil, choose a seed mixture that contains yarrow or clover, for these will remain green when the grass browns. If applying water to the lawn, do it before the grass begins to suffer. For the flower garden select plants that are capable of withstanding dry conditions. A display can then be maintained through the driest parts of the year. Remember, however, that although the plants are capable of withstanding drought they must be allowed to become established first, so that some watering may be necessary during the first year after planting. Plants that can withstand dry conditions once established include:— Annuals and herbaceous plants: Arctotis, gazanias, dimorphotheca, portulaca, livingstone daisies, petunias, French and African marigolds, zinnias, salvias, most summer flowering bulbous type plants and succulents. Shrubs: Bottlebrushes, lavender, rosemary, lavender cotton, broom and Spanish broom. Cistus, Tweedia coerulea, Convolvulus cneorum, Senecio, Grevillea alpina and G. rosmarinifolium, Fremontia californica, Buddleias. Prostantheras, Pelargonium of all types, Rhus cotinus, and Yuccas.