Using a Lawn Scarifier to Remove Moss

Moss can build up on lawns for a number of reasons. The condition of your soil is the most common factor in moss growth. Poor lawn management will also cause moss growth. For an ideal lawn and healthy grass sward your soil should be light and free draining. Grass only requires around 2″ (5cm) of good quality topsoil to grow. But this soil must drain well and be light enough to allow for good root growth. Sandy soils are suitable for good grass growth, but these can require additional irrigation in the summer months. Clay & heavy soils can become compacted and water logged if not maintained correctly and both these factors can lead to moss growth

Using a lawn scarifier will remove moss and thatch from your lawns. This task is best done at the beginning or end of the grass growing season.

When to use a lawn scarifier:

  • April is the best month
  • When grass is actively growing
  • When the ground is damp but not soft. So avoid doing during or just after a rain shower
  • Avoid using a scarifier in the summer months or in winter
  • Avoid scarification in heat, drought & frost
  • April is the best month as grass is starting to grow and will recover quickly from the treatment.
  • Autumn is also a good time as after scarification the lawn will not develop weeds (which can happen after a spring scarification)

The process of scarifying a lawn involves running spring tines over the soil surface, This process has the effect of both removing moss & tatch and loosening up the soil surface. The result is a bare soil surface, which is more airy & bright and therefore, more conducive to grass growth. It can be difficult and tiring work, so you should consider using a mechanical lawn scarifier

When scarifiying you should:

  • First, cut your grass. This will allow for easier scarification. You can cut the grass very short – without scalping it
  • If you want to remove moss, then it is recommended that you apply Iron of Sulphate 2 weeks before scarification
    • Apply 35g of Iron of Sulphate per M2
  • You can use a lawn scarifier, or spring tine rake – both do a similar same job, and both will remove moss. For best results use a lawn scarifier and scarify the lawn in 3 or 4 directions. This will remove the greatest amount of moss.
  • You will find that a lot of moss will be removed from your lawn. This will need to be disposed of.
  • If you find that you are pulling up a lot of grass, then you are being too forceful with the scarifier and/or the conditions are too soft

All types of lawn care will leave the lawn looking worst for wear afterwards. This is especially through for lawn scarification. But the aim of this task is to remove moss and free up the soil around grass shoots. So if your lawn was very mossy to begin with, then after using a scarifier your lawn is going to look mostly bare. This is why Late March / April is the best time to scarifiy, and treat lawns

What to do after scarifiying:

  • Remove all moss piles
  • Avoid excessive walking on your lawn
  • Aerate your lawn. This remove compaction of your soil, increase airflow in the soil, improve soil drainage and improve grass growth conditions. Don’t aerate if the good is soft as this can make compaction and drainage worse
  • Re-seed your lawn. The amount of lawn seed need will depend on how bare your soil is after scarification. Grass should be shown at a rate of 35g per m2.
  • Water lawn seed in

Lawns recover quickly if the weather conditions suit and the lawn seeds in watered in after sowing. If you also aerate after scaritication, the soil conditions will be greatly improved and your grass should perform better. Aeration can be done twice a year to condition soil and reduce moss growth. Scarification can be done once every 3 years to reduce moss and thatch build up