I have St. Augustine grass. What exactly is the process of dethatching? This question went into a brief discussion regarding dethatching.
Are there benefits to dethatching? When is the latest time of the year to dethatch one's lawn?
Thatch is an accumulation of dead organic debris that has not yet been decomposed that builds up between the soil and live grasses. St. Augustine is known for thatch buildup. This buildup blocks water penetration and nutrients. If you can see a 'mat' below your grass and above your soil that is 1" or more you need to use a power rake or manual rake to rip this mat up so that it is mixed with soil and oxygen. This mat will then be decomposed by the decomposers in the soil. In your climate, this should be done late spring.
After this is done fertilize with an organic lawn fertilizer containing bacteria that are responsible for decomposing thatch. Dr. Earth makes an excellent fertilizer for lawns with this bacteria. It costs more but you won't need to fertilize as often. It will take longer than the fast release fertilizer to begin to notice but it works so very well and lasts for months! Worth the money! Hopefully you won't have to de-thatch and this fertilizer will prevent buildup.
Aerate once per year minimum. This pulls up soil plugs that you leave on top of your lawn. Allow them to dry out and they disappear back into your lawn profile by themselves. Meanwhile, the bacteria in the soil should be able to get to work on any thatch that is in the process of building up. The bacteria in the fertilizer ensuring plenty of 'slaves' to do the thatching for you, grin!