Making a Thatch Sandwich - Part 1

Ask most gardeners what lawn thatch is, and they'll tell you it's a layer of loose dead material on the soil surface comprised of old leaves, dead grass and other miscellaneous rubbish collected over the years. Furthermore, the way to deal with it is to give a good hard raking (with a hand rake) in the autumn and, 'Bob's your uncle', problem solved.

Really?

I wouldn't like to tell you just how hard I raked my lawn, blisters and all. Barrow loads of dead material. But no good. Problem still there. It took years to discover why.


JUST WHAT EXACTLY IS 'THATCH'?

Yes, my lawn did have a loose layer of dead material. And this could be removed quite easily. But I was always frustrated to discover that I could never see the soil surface; I had imagined that if I raked hard enough, this would eventually show through. No. All that was there was a dry corky substance.

I don't know why I didn't think of removing a divet of turf (probably because I always thought it would disfigure the lawn). However, when I finally did, I could see quite clearly that this corky layer was about 3 cms (over 1 inch) thick. And it wasn't only comprised of old leaves - it contained dead and live wiry rhizomes (underground stems) twisted into a dense mat. No wonder I was getting nowhere with the hand rake.

A mechanical raker helped somewhat. But unfortunately there was virtually nothing left of the lawn. Yes, it seemed to recover (though I doubt that all lawns would recover without re-seeding). But it looked awful for much of the year. And the problem never seemed to improve.

Now I am trying a new approach:

• minimise thatch and mat production
• enhance natural breakdown of thatch and mat
  

This way, the lawn can be kept looking as good as possible for much longer.

So, to recap, the term 'thatch' is confusing. Apart from loose dead material on the surface, there is often a dense mat beneath the surface, which is much harder to deal with.