How to Keep a Lawn Green Through a South Australian Summer

December 15, 2023

Every year around here people want the lawn looking good for Christmas and the barbecues, and every year the same thing gets it there, which is feeding it at the right time and then watering it in a way that makes the roots go looking for water instead of sitting near the surface waiting for you.

What a lawn actually wants over summer

Feed, water, and a bit of protection from the sun. That is genuinely most of it, and the fiddly bits people worry about matter far less than getting those right.

On feed, go for a balanced slow release rather than something that dumps everything at once. Nitrogen is what greens it up, phosphorus builds the roots underneath, and potassium is what helps it cope when it gets hot and dry. A slow release gives you all three over weeks instead of a fortnight of lush growth followed by nothing.

Timing matters more than people expect. Early summer is the window, while the grass is growing hard enough to actually use what you put on it. And do not spread fertiliser in the heat of the day, because you will burn it. Early morning or late afternoon, then water it in.

Use a spreader if you have one. Doing it by hand sounds fine until you see the stripes six weeks later.

The four things that keep it green

Mow it higher. Longer grass shades its own roots and holds moisture, and a lawn scalped in January is a lawn that browns off in February.
Water deeply, and not often. A long soak twice a week beats a light sprinkle every evening, because shallow watering trains the roots to stay near the surface where the heat is.
Aerate it. If the water is running off rather than going in, the ground has gone hard, and a fork or an aerator will fix that faster than more water will.
Leave the clippings. A mulching mower puts the nitrogen straight back. Free feed, and it saves you bagging it up.

If you would rather not water it all summer

Plenty of people around here do not want to spend the summer on the end of a hose, and that is a completely fair position, so here is how to set the lawn up for it.

Overseed with something drought tolerant, get organic matter into the soil so it holds water instead of shedding it, and keep the traffic down when it is stressed, because a lawn that is struggling does not recover from being walked over the way a healthy one does. Let it grow a bit longer than usual so it shades its own soil.

And then let it go dormant if it wants to. A brown lawn in the worst of February is not a dead lawn, it is a lawn doing exactly what it evolved to do, and it greens back up when the weather breaks. Fighting that costs you a lot of water for a result nobody is measuring. Whether you fight it or not is your call, and either answer is fine.