Dry Patch will appear as random areas of dead grass. Often these areas will be slightly raised areas on the lawn. The lower areas tend to remain greener for longer. The easiest way to find out if your lawn has dry patch is to take a look at the soil. Pick an unaffected area and a dead area and cut an “L” shape with a sharp knife. Dig back the grass and view the soil beneath. The dead area will have bone dry soil, the unaffected area will show signs of moisture often looking darker. You may see white strands of mycelium/fungi within the soil, on the dry sample. This disease is associated with periods of prolonged drought and sandy soils seem to be more susceptible.
What is Dry Patch?
It is not wholly known why Dry Patch is caused however it is believed that it is fungi that create a waxy coating on the soil particles which makes them water-repelling (hydrophobic). This makes it difficult to re-wet. If you throw a bucket of water over the affected area the water will run sideways or sit on the surface.
How do I cure Dry Patch?
Fork or aerate the affected areas, creating channels for water to sit in. A LawnsOne professional operator can apply a wetting agent (these reduce the surface tension of water allowing penetration of the waxy coating). An alternative is to apply used washing up water to the area. Washing up liquid has similar qualities to wetting agents.
Key points to remember
Check the soil beneath, both affected and unaffected areas, and compare.
Create vertical channels for water to sit in and slowly permeate the soil.
It is easier to keep the soil hydrated (watered) than it is to rehydrate once Dry Patch has occurred.