First, in today’s world you must have a really good reason to water a lawn. Second, if your lawn really does need watering, you must follow good practice to minimise the quantity of water. There are three golden rules for efficient lawn watering:
- Avoid shallow or under-watering: this just leads to shallow or poor root development. Make sure the water penetrates well into the soil.
- Avoid the middle of the day when too much water is lost through evaporation. Early morning is acceptable (although a strong morning sun can quickly suck moisture from the ground), but late at night is best as summer grass grows more at night than in the daytime and will use the water more efficiently.
- Avoid over-watering! Too much water will force the air out of the soil and increase compaction. This will damage the soil’s biology and lead to poor root development.
Then there is the question of how often – light and regular/daily or a deep drenching less often? Again, the answer depends on the condition of your lawn and, most of all, your soils. If you have compacted soil, you will waste huge amounts of water through run-off – water that you may as well be pouring straight into the drain.
Finally, remember that old plants will die off during hot spells – it’s natural and no amount of watering will save them.