Lawn Watering

"Brown Lawns are cool in drought" - it's official

Why watering your established lawn is unnecessary...and tips on watering your newly laid turf.

Established Lawns

There is no need to water established lawns.

The watering of established lawns is not only wasteful and unnecessary, it also causes many of the common lawn problems.

So don’t worry if your lawn goes brown during a drought. Going brown is the natural survival mechanism of grass. When water is in short supply grass responds by shutting down. The brown colour shows that the grass has stopped growing until more favourable conditions return.

Watering your established lawn should be avoided in most situations. Here’s why:

• Water is a precious and limited resource.
• Watering increases the chance of disease on your lawn. Most lawn diseases thrive in warm, damp conditions.
• Watering encourages the spread of the weed grass, annual meadow grass. Lawns that are allowed to dry out have much less of this unsightly weed.
• Watering encourages shallow rooting, which in turn means the lawn is more at risk in dry conditions. So, once you start watering, you can’t stop.
• Damp soils are easily damaged by compaction during heavy use, e.g. during family barbeques and games on the lawn.

Grass is remarkably resilient, and as long as you follow a few basic rules, most lawns will recover completely when the rains finally arrive. Below, we give you some ideas on how to plan ahead, and some hints on how to care for your lawn during a dry summer.

Thinking Ahead

Let’s say you’re planning a new lawn. There are two ways to reduce the effects of drought in future years:

1. Increase the water-holding ability of your soil
   Many of the problems associated with drought can be reduced by planning ahead. For example, before you lay a lawn, consider what type of soil you have in your garden. Sandy soils dry out much quicker than clay soils. So it’s worth incorporating lots of organic matter into your soil beforehand. Organic matter increases the ability of all soils to retain moisture.


2. Choose drought resistant grass types
   Grasses with deep roots cope with drought better than grasses with shallow roots. This is because during a drought the upper levels of the soil dry out first. Ask your turf or seed supplier about drought resistant types.

How to look after your lawn during drought

1. Increase mowing height.
   This is one of the most important measures to take. There are several reasons for this. As you increase the height of cut, the depth of root increases in proportion. As a result, the roots go deeper into the ground in search of moisture. Also, the taller grass helps to shade the ground, and shelter it from higher temperatures. Most lawns should not be mown lower than 25mm (1”) at the best of times. In times of drought, lift the height to 35-40mm.


2. Try not to concentrate wear in one place.
   When grass goes brown and stops growing it becomes easier to damage. So try to move toys like slides, swings, and goal posts around so that the wear is spread over the lawn. When your friends come over for a BBQ, try and place it in a different place each time.


3. Avoid feed and weedkiller.
   Brown grass is not growing, so it doesn't need feeding. Avoid blanket weedkillers at all costs because you risk damaging the grass. You can, of course treat individual weeds with a hand-held spot sprayer. Weeds with deep tap roots, like dandelion, can thrive in drought conditions.


4. Keep the mower blades sharp.
   Sharp blades produce a nice clean cut. Blunt blades shred and bruise the grass leaf, and the plant loses more water.


5. Apply top-dressing.
   One of the ways to help your lawn is by applying regular light dressings of compost. This acts as a “mulch” to retain moisture in the soil and protect the grass crowns from higher temperatures.


6. Annual maintenance to reduce thatch.
   The removal of thatch by scarifying should be an important part of your lawn maintenance programme. The thatch layer acts like a barrier to rainfall, and stops precious water getting down to the roots. Regular aeration is another useful operation which helps water find its way into the soil.

Helping your lawn recover after a drought

Once the drought has broken you will be able to assess what effect it’s had on your lawn. But be patient, because it may take a week or two before new shoots start appearing. In most cases, your lawn will fully recover.

If any bare areas persist overseed them with a turf seed mixture chosen to match the existing lawn. Scratch up the surface of the bare ground to loosen the soil before seeding. Cover the seed with a thin layer of compost to help germination, and keep damp for a week. Continue to mow the lawn at a height of no less than 25mm to allow the seedlings to establish without being shaded by the existing grass. Alternatively, buy a few rolls of turf from your TGA turf supplier, excavate the bare areas to the depth of the new turf, and drop the turf in.

A light application of autumn lawn feed will help the grass recover from the stress of summer drought.

Newly laid turf

Newly laid turf needs water to survive. Very often this water will be supplied by rainfall, but in dry spells you will need to keep it damp for the first 28 days by watering.

Watering a newly laid lawn – 10 tips

• When you prepare the ground for turfing consider incorporating a soil conditioner to increase the ability of the soil to retain moisture.
• Plan ahead to prevent the turf drying out: don’t have more turf delivered in a day than you can lay.
• Finish your ground preparation well in advance of the turf delivery. This way, you will be able to start laying the turf as soon as it has arrived. The quicker you lay the turf, the less chance it has of drying out.
• When your turf is delivered, stack it in a shady place.
• Dampen the ground immediately before laying.
• Tamp the turf lightly as you lay it to ensure good contact with the soil underneath.
• When you have finished turfing, water straight away. The first watering should ensure that the soil is damp to a depth of 100mm. Thereafter, aim to keep the turf, and the soil under it, damp – you can check this by turning up a corner of the turf.
• In the days following, water only either in the early morning or in the early evening, so the sun doesn’t burn off the water you’ve added.
• It’s important not to over-water your turf. Over-watering will create boggy conditions - ideal for the development of grass diseases.
• Water less and less frequently over the next 28 days. The turf should never be allowed to dry out and go brown in this period.

After 28 days the turf should be well established and will be able to fend for itself without the need for further watering.