Keep an eye out for Dry Patch. This appears as dry areas where the grass is starved of moisture and then dies.
What is Dry Patch?
Under certain conditions soil can become water repellent resulting in changes to hydrological behaviour, nutrient uptake and plant growth.
Soil water repellency has been recognized in most parts of the world and has been observed in all soil types from sand to clay. Although water repellency in soil has several possible origins, numerous researchers agree that it is caused by an organic coating on the soil particles.
When does it occur?
Water repellency is influenced by season and soil water content. In most cases, repellency decreases during wet autumn and winter months and is most severe during dry periods in spring and summer. Research has shown that patches of soil can become water repellent to a depth of 20 cm or more thus forming blocks of repellent soil which are surrounded by normal wettable soil. Rain and irrigation are not absorbed through the surface of a dry patch or from the water table below.
Dry Patch can be detected with a soil moisture meter. These are available online for less than £10 but you will need a screwdriver to make a pilot hole because the probe is quite easy to break.
1./. With Dry Patch you will get a reading of Dry as deep as the probe can go.
2/. Test green areas around the patch, if they read moist or wet, you know that the dry area is dry patch.
3/ To double check you can remove a plug of soil from the suspected area and, put a drop of water on the soil plug (using an eye dropper). If the water is is not absorbed, you know that it is hydrophobic and therefore it is Dry Patch. With wettable soil the water will be absorbed immediately.
How to cure Dry Patch
Unfortunately many people think that aeration, deep spiking or even pneumatic fracturing will cure the problem – they won't. Dry Patch is a misleading term, Dry Block would be more descriptive because it isn't just the surface that is affected. Micro organisms create a waxy substance that can make blocks of soil unwettable down to a depth of up to a couple of feet. The surface is waterproof and even heavy rain won't penetrate. Furthermore, the bottom of the block can't draw moisture from the water table either. Think of it as a block of wax. If you make holes in it, fracture it or pump air into it the wax will still repel water. The cure is very simple, all you need is a watering can or a sprayer and a bottle of curative. The affected area is sprayed twice, leaving 14 days between applications. It is best to treat before rain or water in afterwards to get the product into the root zone. Dry Patch Curative is available in my shop here
Dry Patch creates dead, dried out patches on a croquet lawn surrounded by perfectly green areas. So the lawn develops very fast patches of dead grass which makes some croquet shots a pure lottery. If there are small local dry patches it can cause the earth to contract and become bumpy. The result is that accurate shots become unintentional jump shots and can result in the loss of a game. So it can be very very annoying for players.
As stated above, it can be treated but unless you catch it at the very early stages it can take weeks for the grass to grow back especially mid season and it may not fully recover during the season. So where Dry Patch is a recurring problem a preventative programme of treatment needs to be employed.