Ever wondered why the word for “to scrape out all the moss and dead grass from your lawn” is Scarify?
Answer - because it's pretty darned scary-fying to do it!
You start with what appears to be a nice, normal, green lawn: you apply the autumn “weed and feed” product, either by trundling a little cart up and down the lawn, or by doing the old-fashioned broadcasting by hand, with sweeping arm motions: then a fortnight later you are confronted with big black patches where the moss has been killed, and you look at it in horror and realise that you can't just leave it, you have to get out there and scrape out the dead stuff.
If you are lucky, you'll have a little electric scarifier, which looks like a cut-down mower but with long thin teeth instead of a blade: if you are less lucky you'll have an ecologically-sound hand-push scarifier, which looks like a minimalist rake on wheels: or if you are really unlucky you'll just have the good old Spring Rake, which we use in Autumn (gardeners' joke).
Whatever tool you have, when you start to apply it to the lawn, masses and masses of moss will spring up in an apparently endless supply, leaving you with scary bare-looking patches, and a massive bagful of fluffy green stuff that cannot be put on the compost, as it is mostly moss, and therefore you would end up with compost full of moss spores. And you certainly don't want to spread the moss around the garden any further!
The photos above show me doing this for a Client, using a folding Spring Rake ("which we use in Autumn"... gardeners don't have many in-jokes, so we have to make the most of the ones we do have) which I find does the job better than a “fixed” one, as you can alter the width of the tines to get the best effect.
Although I use the word “scrape” it's actually quite a light combing action - the trick is to get the moss out but to leave the grass behind, so there's quite a lot of upward motion. Great for the stomach muscles, allegedly: I ought, by rights, to have the female equivalent of an impressive six-pack by now but alas, I'm still soft and squishy (sighs) in the stomach department. But at least the lawn is looking better!
I generally comb it once in one direction, then at a right angle, then again in a swirling motion in order to a) get the last of the moss out, and b) remove the rather odd partings that you get, if you just rake in straight lines.
Having removed the moss, you can then scatter a little fresh lawn seed on the bare patches, and they will soon green up again.
There, all done!
Well, not quite: it's an unfortunate fact that if you have moss in your lawn, just raking out the existing moss won't cure the problem, and that's another whole subject: but at least by removing it annually you can prevent it taking over the grass completely, and it gives the grass a chance to recover. September is a great time to do this, so get your weed'n'feed applied, wait a fortnight, then get raking!