Dry spots in your lawn? (heat stress)

CALL US (07) 5543 8304

Dry spots in your lawn? (heat stress)

06 February 2019 General Maintenance Seasonal Advice

Hot and dry weather can really take a toll on even the healthiest lawns and cause them to become thin and patchy. This usually happens over the summer months, as the weather is hot and dry.

A common misconception we see & hear (especially on social media) is that any brown patches are caused by lawn grub, while this can be possible if the weather is hot & dry, a lot of the time it's just dry patches, but it's always worth checking for lawn grubs anyway (see this article) as this costs you nothing & can save you money on treatments that you may not need.

Heat stress stages & symptoms

  1. The first sign of heat stress 'stage 1' is usually a blueish/silver tinge over your lawn and some shrivelling of the leaf (refer image on left below),
  2. Then those silver leaves turn to a bright yellowish/brown, this is 'stage 2' and the leaf has started to go into dormancy now, note that is hasnt dropped in height and still looks the same as the healthy turf next to it, just discoloured, your lawn can still be revived at this point in most cases, if you get onto it straight away,
  3. If still not rectified the leaf will break and fall off, leaving dark brown patches that are down to ground level, leaving your lawn looking klumpy and uneven and sometimes bare dirt can be exposed (refer image on the right below), this is the 'final stage' of the process and it usually cant be revived once it gets to this point, your only choice is to wait for the healthy turf to slowly spread over, or re-turf it.

Dry patch forming process from left (start of drying) to right (neglect has left grass to die)

Drying Turf - 3stages.png

The bare patches bake in the sun and the soil becomes rock hard (hydrophobic) making it difficult for water and nutrients to get into the soil.

How to treat dry patches

It is always a good pactice to aerate the affected area of your lawn, aeration can be done with a garden fork, aerator sandals or a specialised aerator machine depending on the size of the lawn. This is crucial as it will de-compact your soil and will help nutrients and water penetrate your lawn.

Next, apply a wetting agent to the affected area. Wetting agents come in liquid and granular forms and assist with water absorbing into your soil. This will also allow the soil to hold water in a usable manner for longer. Always remember to irrigate your lawn well after applying the wetting agent, we reccommend HydraMaxx from Lawn Pride Australia or 'Amgrow Wettasoil' from most hardware stores.

After this (a few days after the wetting agent) it is time to boost your lawns growth to allow it to self-repair and cover back over. This is best done by applying a light-moderate rate of NPK fertiliser to the entire lawn and irrigating the lawn well afterwards. Always remember to apply all products at label rates and follow all instructions, for long term slow release we reccommend GTS MAINTAIN from Lawn Pride Australia, and for a quick boost Seasol (hardware stores) is great too and because Seasol is organic it can be used as often as needed.

Future Prevention & Ongoing Maintenance

Here are some steps you can take to reduce the suffering.

  • If re-turfing choose a drought tolerant variety & carry out good soil improvement practices prior to installing
  • Avoid applying lawn grub poison or other herbicides unless you're sure you need to
  • Water your lawn correctly; less frequent, deeper soakings to encourage deep roots
  • If possible, give your lawn one deep soaking at the first sign of any heat and drought and then leave it until it starts to wilt, repeating the process as necessary. This will be more frequent in sandy soils NOTE: this applies to established lawns only, not new installs
  • Apply wetting agents again at the start of spring (September), and then again in the new year

As always, if you have any more questions please dont hesitate to contact us for free expert advice on 1800ALLTURF (1800255873) or LiveChat with us using the chat box in the bottom right corner of your screen.