There are three general categories of dethatching rakes: manual, tow-behind and powered, also frequently referred to as power rakes. While they differ in price, size and operation, they will all remove excessive thatch build-up from your lawn when used properly.
Manual dethatching rakes. A good-quality manual dethatching rake should be among everyone's lawn care tools. They only cost around for a well-made rake that will continue to do a good job for 10 or more years. These rakes look similar to the more common leaf or garden rake, but the tines are very sharp along both edges. They are easy to use: just put the bottom on the tines on top of the dirt and pull the rake through the thatch layer back to your body. The thatch will come up best if you vary the direction of your strokes. It can be a bit time-consuming to do a large amount of grass this way, especially if the thatch layer is very thick, but most lawns are fine with regular manual dethatching. These rakes are also great for attacking spots that build thatch more quickly in-between overall lawn dethatching or for working on any places that were missed.
Garden Rake
Tow-behind dethatching rakes. Designed to attach to the three-point hitch of a tractor or to a riding lawn mower, these dethatchers are wider and cover more ground at a time than other types. For the best results, go over the lawn twice in a crisscross pattern. Always make sure that the dethatcher is properly attached before beginning and check to make sure the blades are going in the proper depth.
Power dethatching rakes. These machines are powered by electric or gas motors and resemble lawn mowers. The blades along the bottom are adjustable. The best models contain several height and width settings that allow versatility for the type of grass and the thickness of the thatch layer. After adjusting the blades, start dethatching and then stop to check that they are skimming the surface and pulling up the thatch correctly. Go in crossing diagonal rows or perpendicular ones to thoroughly remove the thatch. Some machines feature a collection box that will save you from having to rake up the thatch that is removed. These dethatchers can be expensive to buy (from one to several thousand dollars), but rent for around a half-day.
Comparing Types of Dethatching Rakes