When, and how much water do I need to irrigate on my lawn? These are the questions I am going to attempt to answer in this article. The exact amount required by the lawn grass and when, would need a private consultation, and then the answer could only be given when average precipitation levels and soil temperatures are known.

With this in mind, here are a few tips on how your grass will show it requires watering. Firstly, broad leaf grasses tend to roll the leaves to conserve water. They do this to lessen the surface area exposed to the sun and heat, reducing transpiration, but also reducing photosynthesis which can show up as a slight yellowing of the grass, grass leaves with brownish edges that are dry, are evidence of dehydration. Grass observed from a low angle, that appear yellowish, but when observed from a high angle, or directly from above, show up green, is an early warning sign of grass requiring moisture.

Other thinner leafed lawn grasses, will leave evidence of mower movement, or footprints, long after the indentations made. This is because the leaves being dry become dehydrated and lack the potential to spring back to their original position or shape. Dry leaves lose their pliability, and foot prints and mower prints actually break the surface structure of the leaf. “Hot spots”, or localised yellow patches are a sign to irrigate, these are normally areas of grass with a short root structure, and drying out occurs faster in a short root system than a deep root system.

Now how much water to apply during the irrigation period? Short daily applications are not recommended, all this achieves is the dampening of the top soil structure with little to no moisture penetration to deeper roots. This results in the plant producing surface roots, and the deeper roots dying back. The problem arising from this, is the grasses ability to withstand drought conditions when precipitation and water restrictions, for various reasons, come in to play.

It better to apply deep or heavy irrigation, less often, (as continuous over watering can cause other problems) than lighter applications. Heavy applications of irrigation enough to dampen the soils to a depth of 5 to 6 inches or 125 to 150 mm. This would probably convert to an inch, or 25 mm, of rain. The depth of moisture can easily be determined by inserting a spade in the soil and applying a lateral movement, so that the lower depths are visible. Trial and error, being the catch phrase, when applying these amounts of water, time the application and measure the depth of water collected in a can or rain gauge place under the sprinkler, and then check the soil penetration. This will enable you to set your irrigation systems computer, or allow you to time applications and move sprinklers when required. Deep applications encourage roots to grow deeper and empowers the plant to better combat drought. As well as, the deeper the water table, the less evaporation or transpiration that can affect the moisture levels, takes place.

The rule of thumb is apply an inch or two per week in the high heat periods and less in the cooler times. Apply sufficient to equate to an inch of precipitation per application and watch the grasses growth patterns as well as for signs of dehydration. Take the precipitation into account by maintaining a rain gauge or udometer, and work the natural applications into your program.

Under no circumstances over water your lawn, this leads to diseases, soggy patches in the lawn and anaerobic conditions.