When to fertilise a Toowoomba lawn (and when it's money on the ground)

Most of the fertiliser we see wasted in Toowoomba isn't the wrong product. It's the right product at the wrong time. Warm-season grass only uses food while it is growing, and a bag spread outside that window mostly washes away.

Feed while the lawn is growing

Couch, kikuyu and buffalo, which make up nearly every lawn here, go dormant with the winter frosts. A dormant lawn isn't eating. Feed it in July or early August and the nutrients sit in the soil until the next heavy rain carries them off, long before the grass wakes up.

The trigger for the first feed is green-up you can actually see: new leaf, colour returning at the base, growth between mows. In most of Toowoomba that is September. At elevation — Highfields, Hampton, Mount Kynoch — it can run a fortnight or more later.

Three feeds a year

A decent controlled-release granular fertiliser releases over two to three months, so three feeds cover a full Toowoomba growing season:

• September, once the lawn is genuinely growing.
• December, ahead of the heat.
• February into March, the last feed before growth slows for autumn.

A fourth bag inside three months of the last one is money on the ground. The lawn can't use it, and the excess leaches away.

Watering it in

Slow-release granular feed doesn't have to be watered in the same day; it releases with soil moisture and temperature. Watering that evening or within a few days gets it working about a week sooner. Avoid spreading it in a frost or a drought, when the lawn can't use it and you can't water it in.

Feeding and weeds

On a lawn that is mostly grass, feed first and treat broadleaf weeds ten to fourteen days later, while everything is growing hard and taking up the spray. On a lawn that is more weed than grass, spray first and feed two to three weeks later, so the grass fills the gaps before the weeds do. Clover in particular is a sign of a hungry lawn — see why clover means your lawn is hungry.

When to hold off

• Fungal disease. Brown patch, dollar spot or rings after humid weather: hold the nitrogen back, because it feeds the disease as readily as the grass. Resume two to three weeks after it is under control.
• Water-repellent red soil. If water beads and runs off dry patches, the fertiliser won't get in either. Fix the soil first with a wetting agent — see why part of your lawn won't soak up water.
• Compacted black clay. Core aeration first gives the feed somewhere to go. A granular feed about a week after coring goes straight down the holes to the roots.

Want it done for you?

We fertilise as part of our lawn care and renovation work, timed to your grass and your soil, and it can go down on the same visit as your regular lawn mowing. Quotes are free and usually back within 1 business day.