Moss in the lawn

Moss, for many gardeners is the most annoying of all the problems associated with lawns. Moss is most commonly a problem on the lawn during spring time.

This is especially true especially if the winter weather has been poor and grass has become thin and weak and moss has been allowed to flourish.

Mosses are primitive non flowering plants that have no root structure, they rely on moisture being available in the environment to spread. Although there are over 10,000 types of moss they fall into 3 different groups.

• Cushion moss - these are associated with lawns that are closely mown and where scalping of the turf has occurred.
• Trailing moss - this type of moss is usually found on lawns with poor drainage or suffer with shade.
• Upright moss - this type of moss is associated with drier soils often with a low soil pH (acidic).

Why do I have moss in my lawn

Like many lawn care problems the conditions in the lawn have to be favourable for the moss to encroach. Moss can invade a lawn when any of the following conditions are present.

• Excessive periods of wet of dry weather
  
• Soils that are deficient in nutrients (low fertility)
  
• Compacted soils
  
• Very low soil pH
  
• Lawns that suffer from excessive shade
  
• Poorly drained soils
  
• Lack of air circulation
  
• Turf that has been weakened by close mowing
  
• Poor lawn and turf maintenance
  

How to prevent moss in a lawn

As with most lawn and turf problems, prevention of the problem is better than the cure. Moss will only be a problem if any of the above symptoms are present.

It may be impractical to remedy all of the conditions that causes moss, in fact some maybe beyond our control, so concentrate on correcting the causes that apply to your situation.

• Maintain a balanced fertiliser program that keeps the sward thick and healthy giving moss little opportunity to invade.
  
• Aerate the lawn to relieve the soil compaction.
  
• Remove thatch if it has become excessive. Thatch is usually one of two extremes, very wet or very dry, both favour moss development.
  
• Improve the airflow over the surface of the lawn, this will help keep the surface of the lawn dry, helping prevent moss.
  
• Reduce the shade by selective pruning of trees, grass growth suffers badly in areas of poor light, which in turn gives moss the ideal opportunity to out compete the grass. This is why moss is always a problem during the winter.
  
• Avoid over watering the lawn.
  
• Avoid mowing the lawn to closely especially late in the growing season.
  

How to control moss in a lawn

Once moss has invaded and the quality of the lawn has deteriorated somewhat, some form of action will be needed to remove the moss from the lawn.

The most common product used to control moss is sulphate of iron. This ingredient can be found many products such as lawn sand, feed weed & moss killer products and many more available in both granular and liquid formulations.

These products are usually applied during the spring time when moss is most problematic and as the grass is showing signs of growth to promote quick recovery.

Once the moss has been killed (usually after 2 weeks) it can be removed from the lawn using a spring tine rake of a garden scarifier. Once the moss has been removed from the lawn you can then proceed with the rest of your spring renovation program.

This can include aerating, overseeding, top dressing and feeding the lawn.
However it is important to note that if the conditions causing moss are not corrected it will continue to be a problem.