Lawns which suffer from lack of water first lose their resilience, which is shown by footprints remaining on the dry grass. The colour fades, then turns brown and the grass dies. the roots may remain alive long after the top dies and the lawn can be revitalised when it receives moisture, but it will suffer if it is continually allowed to die back in dry weather. Some lawns are more drought-resistant than others, and lawns seldom die permanently through lack of water, but should be watered thoroughly during summer if rain does not fall for about a week.
Evergreen lawns need moisture all through the year and must be watered regularly once or twice a week if rain does not fall. One should give the lawn a deep thorough watering once a week in order to encourage deeper, cooler roots, which may go down to 30 cm or more. Daily sprinkling will cool the air, but will not supply enough water for the lawn’s needs. Water is lost by evaporation in dry ares. One aims to replace the lost water when watering the lawn each week. The lawn requires at least 5 cm of water replacement in hotter, drier inland climates. This will sink down about 40 cm into the soil. When the soil is allowed to dry out completely, the lawn will die.
A lawn sprinkler will have to remain in one spot for about two or even three hours in order to build up 3 cm of water. Sandy soils will be more quickly penetrated than clay soils, but also dry out more rapidly and will require more frequent watering than clay soil. Do not leave the sprinkler in one position until pools of water collect on the surface, and turn off automatic sprinkler systems when this happens or the grass will become scalded. The water will not be absorbed by the roots because of lack of air – transpiration continues to take place through the leaves – a drying out effect will result.
It is essential to purchase a good lawn sprinkler in order to care for your lawn easily. Try to obtain a sprinkler that will cover a large area. Allow a small amount of overlapping to take place when moving the sprinkler. There may be hard spots on the lawn which are not penetrated by the sprinkler. Aerate the areas with a hollow-tined fork and allow the hose to run slowly on to the spot and penetrate it deeply.
Sprinkler systems can be sunk into the ground and will water the lawn evenly if they are scientifically worked out. These may be placed in the soil before planting or sunk into an existing lawn. The pipes may be made of iron piping, plastic tubing or other materials. Sprinkler systems which water the whole lawn at the turn of a tap are not really necessary if there is sufficient labour available.