My experience with irrigation, began very early in life, when still a child at home in the southern regions of Rhodesia, living in an area that surpassed qualifying as a desert, by the finest of margins. One of my duties or chores as a child, when home from boarding school, to aid mother by watering the meagre lawn and garden of plants the size of a postage stamp.

The soils consisted of fine sand, with little or no organic material for moisture retention. The daily temperatures reached the excessive highs experienced by certain areas of the country, and moisture, at the hotter periods of the day, would evaporate faster than could be applied. Now, as a hose pipe was not the method of application, but rather a watering can, filled from a sunken 1000 litre corrugated iron dam, this took time to apply. The heat became a discomfort and between fills, short swimming breaks taken in the dam.

I experimented by attempting to splash water from the dam over the area whilst swimming, but discovered the small Eden was beyond my reach. I had to have another idea, and asked if I could water in the evening during the cooler periods. This was not for the plants sake but rather for mine. Allowed to follow this request, I discovered one of the basics of irrigation, I could water the areas, without it all disappearing, before returning with the next can full. Cooler times, less evaporation, a discovery that was to aid me in later years.

Years on, when I had contracts with the mines, for their gardens, I again experienced the difficulty of ensuring moisture levels within the soils, as the mines are situated in the lower, hotter areas of South Africa. These mines at that time, not equipped with computer controlled irrigation, had very little sympathy with my difficulties. They paid me for a duty, with no concern as to how I performed it, but rather used a clause of “non performance” as a “carrot” to guarantee the gardens remained in top condition.

After being contracted to landscape a new area, and to spend an enormous amount of money on plants, they half condescended to allow me to install a computerised irrigation system. They would not pay for this, unless I could show a significant saving in water. Preceding the installing of the system, they fitted a water meter on the dedicated line to the garden, and for a month I hand watered using hose pipes during the normal working hours of the day. This usage was closely monitored by the Contracts Manager.

At end of the month, having installed the sprinkler system during the previous month, at a high cost to myself, the computer connected and the irrigation executed late at night, during the coolest period. Knowing the application rates of the system, and the amount I required for the plants, it was easy for me to pre-set the computer to apply sufficient water to ensure growth. The first night's application was too high, and I adjusted the running time required. This at the end of the month reduced the water used to 45% of the previous month. They paid for the system, and instructed me to cover the entire garden area with irrigation.

Now the moral of the story, it is better to irrigate gardens at midnight, during the summer months. In winter, if the area experiences frost, early morning. Why the early morning when experiencing frost? Because the water applied at the right time, is warmer than the ground temperatures during the frosting period. This warmer water will aid the lawn or plants to resist the cellular damage experienced during frosting. The timing must be correct, too early and this water can freeze, and too late and the cellular damage may have already materialised. But suffice it to say, that with experience this timing is easy to predict.

A well installed, reliable irrigation system will pay for itself in no time.