Core aeration, hollow tining the lawn

Types of core aeration machinery

Core aeration or hollow tining can be undertaken with either a powered lawn / core aerator, a tow-behind aerator or a simple hollow tine hand fork.

• Powered core aerator - These machines are generally powered by a petrol engine and are designed to cover large lawns in a short space of time. The tines can either be mounted to a cylindrical frame, drum or spool which penetrate into the turf as the drum rotates over the lawn.
  
  Alternatively the tines may be mounted on legs that are attached to a cam type system. On this type of core aerator the tines are punched vertically into the lawn to remove the core or plugs. Punch action core aerators generally penetrate deeper into the soil than drum type aerators.
  
  

  The process of core aeration involves the removal of small cores or plugs from the soil.

  The main disadvantage of these machines is the cost of purchase. In most cases it is better to hire rather than purchase a powered core aerator, or use an alternative method to aerate the lawn.
  
  
• Tow-behind core aerator - As the name suggest these core aerators or towed behind a garden tractor or similar. The tines are fixed to a drum or spool, which penetrate into the lawn, removing the cores as it travels over the lawn. Some models have a weight tray to add extra weight to the machine to increase tine penetration.
  
  Tow-behind aerators are great for large areas, and the cost of purchase is quite reasonable making them an ideal alternative to powered core aerators. The main drawbacks are the tines lack of penetration depth, and they are unsuitable for small, tight lawns.
  
  
• Hand core aerator fork - These simple tools are very popular for core aeration, and are designed similar to a hand fork, but hollow tines replace the standard fork tines. They are simply pushed into the soil to remove the cores.
  
  These implements are ideal for smaller lawns where larger machinery is difficult to manoeuvre. They are not really suitable for large lawns as they are very time consuming and they can be very laborious. If used when the soil conditions are moist, full tine depth can be reached, ensuring a very thorough job.

Why core aeration

There are numerous benefits that core aeration has over standard lawn aeration such as spiking and slitting. As we have already stated core aeration (hollow tining) removes cores, while other types of aeration just punch holes in the lawn. The major benefits of removing cores are:

• Reduce the influence of thatch in the lawn - An excessive layer of thatch in the lawn is one of the primary reasons for poor lawn health and countless other common lawn care problems. Hollow tining or core aeration physically removes the thatch from the lawn, resulting in a healthier lawn with fewer problems.
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• Incorporate a soil exchange program - Many lawns suffer from various problems such as lack of drought resistance or poor drainage. It is possible that these problems can be alleviated with core aeration. As core aeration leaves wide, deep holes in the lawn, a suitable top dressing can be applied and worked down the core holes and into the soil. If done on a regular basis the soil composition can be gradually changed to help rectify the underlying problems with the soil.
  
  
• Relieve soil compaction - Although all types of aeration help relieve soil compaction, core aeration is more beneficial than other types of lawn aeration. This is because where the cores plugs have been removed the surrounding soil is allowed to expand, thus being more effective at reducing soil compaction.
  

When & how to core aerate a lawn

Although core aeration can be carried out at almost any time during the year (ground conditions permitting) the growing season is best time, late summer or early autumn being preferable. This is because it compliments the autumn lawn care program, which also includes overseeding and top dressing. Both of these two tasks will benefit greatly from core aeration being carried out prior to them.

However if you have a serious problem with excessive thatch build up, or need to change the composition of the soil by applying top dressing, then core aeration can also be undertaken during the spring or even at suitable times during the summer, again weather and ground condiotns permitting.

This task is best carried out when the lawn surface is dry. Prior to aerating, mow the lawn, as this will help with core collection.