Andrew wrote:

Andy Burns wrote:

The 9x9" gulley surround at the bottom of my downpipe is packed full
of [moss] at the moment ...

Local Sainsburys is selling off their garden stuff cheap at the
moment. Lots of readymix sprays for killing moss and weeds.

I doubt the sprayer is powerful enough to reach the roof, I suspect the
dry spell followed by a couple of downpours loosened it (with assistance
from the jackdaws).