Watering your lawn: the case for doing it less

The nightly ten-minute sprinkle is the most common watering mistake in Melbourne. It feels responsible, and it quietly trains your lawn to fail: the water sits in the top couple of centimetres, so that's where the roots stay, and a lawn with 3 cm roots cooks the first week of February while your neighbour's neglected kikuyu shrugs it off.

The principle: deep and rare

Roots grow where the water is. Soak the soil 10-15 cm down, then don't water again until the lawn's used it, and the roots chase the moisture downward. A deep-rooted lawn drinks from a bigger tank - that's most of what "drought tolerant" means.

• Established lawn, warm weather: one or two proper soaks a week beats seven sprinkles - roughly 10 mm or more per session, which for most sprinklers means 30-45 minutes per zone. Put a straight-sided container (a tuna tin does the job) under the spray and time how long 10-15 mm takes; you now know your system.
• Cooler months: most Melbourne lawns need nothing from you between May and September. Rain covers it; dormant couch and kikuyu barely drink anyway.
• New turf or fresh repairs: the exception - light and frequent until it roots in, then taper to the adult schedule. (See fixing a patchy lawn.)

Water in the morning

Water before 10am. Early watering reaches the roots before the day's heat starts stealing it, and the leaves dry as the sun comes up. Evening watering leaves the lawn wet all night, which is a written invitation to every fungal disease going. Nobody's thrilled about 6am, which is why sprinkler timers exist - and Melbourne's permanent water saving rules point the same way: a sprinkler or watering system may only run between 6pm and 10am, though a hand-held hose with a trigger nozzle is allowed at any time. If you're on a manual hose, morning coffee plus sprinkler is a fine system.

How to tell when it's time

Skip the fixed schedule and read the lawn instead. Three easy checks:

• The screwdriver test. If a screwdriver pushes into the soil easily, there's moisture. If you're leaning on it, water.
• Footprints. Walk the lawn: hydrated grass springs back, thirsty grass holds the footprint.
• Colour shift. Grass going dull blue-grey-green is asking; brown is dormancy already underway (recoverable - see the dead grass guide).

When water isn't the problem

If water pools or runs off instead of soaking in, more watering won't help. Compacted soil and thick thatch both keep water from getting down; aeration fixes the first, dethatching the second. And a lawn mowed too short needs far more water than one cut a notch higher - taller leaves shade the soil and slow evaporation. The cheapest irrigation upgrade in Melbourne is raising the mower deck one setting.

Quick answers

How often should I water my lawn?

An established lawn in warm weather wants one or two deep soaks a week of 10 mm or more, not a nightly sprinkle. Most Melbourne lawns need nothing between May and September. New turf and repairs are the exception: light and daily until rooted.

What time of day should I water the lawn?

Before 10am, so the water reaches the roots before the heat and the leaves dry as the sun comes up. Evening watering leaves the lawn wet all night, which invites fungal disease. Melbourne's water rules allow sprinklers only between 6pm and 10am.

How do I know when the lawn needs water?

Three checks. A screwdriver pushes into moist soil easily. Hydrated grass springs back from a footprint; thirsty grass holds it. A dull blue-grey-green colour means it is asking; brown means dormancy is already under way.