There is often a lot of confusion between power raking and dethatching. This confusion is understandable because they are in fact essentially the same thing. The difference between them lies only in the method and effectiveness of the process.
Let me explain, but first, let’s make sure we know exactly what thatch is.
Different Types of Grass
Some grasses propagate slowly if no seed is added. One common such lawn grass is ryegrass. Ryegrass is called a bunch or clump grass. In essence as a bunch grass grows it sends out tillers which thicken the grass, and eventually it will spread out considerably. But this can take a long time and in the meantime bare patches in your yard will appear, well, bare.
Other grasses send out underground runners. These runners bury their way through the soil and pop up away from the original grass plant. These new shoots thicken out and in turn spread their own runners. These types of grasses tend to fill bare patches in a lawn quickly and effectively and for this reason are a popular choice for lawn seeds. Bentgrass is one such seed.
How Does Thatch Form?
Side view of thatch in turf. Image source Lincoln Landscaping
Some of these grass runners succeed and the turf thickens and develops nicely. Some become tangled up with trapped grass clippings and dry roots till they die off. In effect the lawn gets all tangled up in itself.
This tangled layer of dead grass and clippings and other debris (leaves and moss) is thatch.
In most mature landscape lawns this matted decomposing layer is ok and does no harm to the acreage. In fact it should provide a degree of sponginess underfoot and returns many nutrients to the soil meaning the grass can produce automatic self seeding effect, sustaining fresh grass shoots.
A typical thatch layer might be ½ inch thick. But in some lawns, especially if excess fertilizer or overseeding has been used, the thatch builds up to as much as 3 inches thick and begins to starve the new grass shoots of room.
Ryegrass, being a bunch grass does not typically produce thatch. This is why it makes it popular for the reluctant gardener as detaching is not necessary, but one of the cons is it also means it is not as thick, spongy and luxuriant as bentgrass alternatives.
In any event it is a good idea to remove by detaching periodically, this removal of clippings is in order to allow the grass to thicken and develop freely, so your yard looks great for those springs and summer months. Ever since I became a dethacher, my landscaping difference is amazing you really see the large benefits compared to before. General advice is that detaching can be carried out once per year, but of course local conditions may make a big affect this. Regular aeration can prevent the thatch from becoming bad too.
Manual dethatching rake.
Dethatching is the process of removing the build-up of thatch in the lawn. It is as simple as that.
There are a number of ways of aerating. The easiest but perhaps least effective is to use a thatching rake to comb through the grass, pulling and lifting to pick and clean up the dead material out manually.
Because the thatching rake method is manual, it has two problems. It is both hard work and it is really only suitable for smaller areas.
The pros are the cost, the it has a cheap price compared to the motorized mechanical counterpart prices. You also cordless therefore you don’t need a heavy duty electric cable attachment if you are doing work away from your average short yard.
If you have a larger lawn or your thatch problem is particularly acute, instead of the hand dethatching option you get a powerake dethatchers, which are both commercial and domestic purpose machines.
Power raking is essentially powered, systematic dethatching using a powered vertical mower to actually do the work vs the hand comber all you have to do is walk behind it and it will detach everything for you.
In short is a dethatching machine.
It is operated by the blades of the vertical mower or power raker are adjusted to the correct height to just cut and get the thatch debris out, but not actually damage the healthy grass and grass roots.
Power raking is much more effective than manual dethatching. It is not unusual for a power raker to lift out four times as much thatch as the manual equivalent making it a much more effective option.
In summary, detatching is the process of removing thatch from a lawn in order to encourage growth and prevent lawn strangulation. A power raker is a machine that performs the dethatching process.
All power rakers are dethatchers, but not all dethatching tools are power rakers.
If you are still confused as to the difference, take a look at this video which shows each type of rake in action.