Dethatching is becoming more popular in lawn care thanks to videos online and other sources. But this has led to a lot of confusion about the topic. The person who posted this is sharing info to clear things up.
Thatch is made of living and dead grass stems and roots on top of the soil. Grass clippings are not thatch and don’t add to it. You can only check how much thatch there is by digging in.
Having some thatch is actually good. Some sources say that less than 1 inch of thatch is okay, with most people saying half an inch is best. Thatch can help with things like preventing weeds, handling foot traffic, and protecting against heat and moisture loss, so it shouldn’t always be removed. If there’s over half an inch of thatch, it’s best to figure out what’s causing it. If there’s an inch or more, that definitely needs attention. Regularly dethatching without a real issue isn’t a good idea… Some thatch is beneficial.
Thatch problems are not common. Too much thatch is usually a sign of other issues, like too much fertilizer, too much watering, frequent use of fungicides, heavy use of certain insecticides, or certain types of grasses.
Using a flexible tine dethatcher (like a sunjoe) can harm lawns both in the short and long term, and it might increase the spread of certain weeds like bentgrass. In rare cases, the damage might be necessary, but you’ll want to follow up with seeding.
A much better way to handle too much thatch is core aeration. Core aeration doesn’t really remove a lot of thatch, so it doesn’t take away much healthy grass either. But it can help speed up the natural breakdown of thatch.
Other less damaging tools than flexible tine dethatchers are verticutters and scarifiers.
If you’re thinking about overseeding, try less harmful methods like slit seeding, scarifying, manual raking, or tools like a Garden Weasel. You can find more on seeding in the guide here.
Also, look at the list of causes mentioned to make sure you’re not overlooking anything.