In message , J99
writes
Is it too late in the year to scarify my lawn? (Using a powered
scarifier) There is a lot of moss and thatch in my lawn, but I wonder
if I would be doing more harm than good scarifying at this time of
year?

thanks for any advice

Julian
The simple answer is "probably"
Best time is early autumn to remove debris and thick thatch. If moss is
present (and you want to get rid of it) treat with a moss killer a
couple of weeks before scarifying.
Do not scarify in early spring as the grass does not produce side shoots
at this stage and so you would open up the turf making it vulnerable to
weed invasion. Use in late spring/early summer if required to remove any
patches of dead moss if you have used a moss killer.

If your lawn is not too wet, and the weather reasonably mild then if our
lawn is as bad as you say it is then it might be worth going over it now
but not too vigorously, just to remove the thatch. Leave the moss
problem until the Spring
HTH
--
hugh
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