Dry Patch

What is Dry Patch?

 

Regardless of how much rain we often seem to get in the UK (and don’t we love to complain about it!), Dry Patch is a phenomena which happens to lawns during the summer when soil conditions have become so dry that water is no longer able to penetrate into the soil. This means that even when rain returns the soil has become hydrophobic (water-repellent). Dry Patch is also closely linked to another soil borne lawn problem called Fairy Rings.

 

Note – localised dry patch is not the same as having a dry lawn. A lawn turning brown and dormant can be cause by drought or heat stress as well as a lack of moisture. In these cases the grass will turn brown as its defense mechanism. Dry patch is a condition that affects the soil, having a knock on affect to the grass on the surface.

 

When will I notice it and how do I know if it is Dry Patch?

 

Dry Patch often occurs during late-spring and summer months. You will often notice sporadic patches of grass turning brown and appearing to die off. This is because Dry Patch can be very localised, and only affect some areas of your lawn and not others.

 

An effective method of checking your soil for dry patch is to remove a core of soil from your lawn and gently apply a small amount of water to the soil. If the water soaks in it is not dry patch, however if the water runs straight off it might be the start of a problem.

 

Why does Dry Patch occur?

 

This condition often happens in lawns that have become old or where the soil is poor and natural healthy bacteria cannot work efficiently. The affected areas of the lawn dry out as a consequence and turn brown as they are unable to absorb enough moisture to keep the grass plant healthy.

 

Hydrophobic conditions are caused by a white, waxy mycelium fungus in the soil which prevents any water from penetrating. Hence, the grass looks poor, especially during periods of dry weather when the underlying problem is exposed. It is often impossible for the soil to absorb any water, no matter how much you apply.

 

A thick thatch layer and compacted soils can cause dry patch as they prevent vital air, moisture and nutrients from penetrating the soil.

 

How do I rectify my Dry Patch issues?

 

Managing dry patch should be done via preventative measure to try and stop it affecting your lawn in the first place. Fixing the issue and ‘re-wetting’ the soil once it has occurred during the warm, dry months of summer can be extremely challenging.

 

  • Carry out regular aeration and scarification on your lawn to reduce compaction and control thatch layers. This will improve the air, moisture and nutrient flow to the soil.
  • If you are experiencing dry patch at a time that is unsuitable for aeration and/or scarification, spike the dry patches with a garden fork and water regularly.
  • Consider the use of wetting agents. Wetting agents are a often used on sports turf and aid the soils ability to absorb water. They are best used at the same time as the cultural methods above.