"AL_n" wrote in
:

wash off 'growers' on grave stones.

Thankd=s for the tip. Bleach certainly seems to work well for mildew.
Having said that, the last time I killed some inderior mildew with
bleach, some other form of growth took over. It looked like white
fluff! When I saw that, I thought "Ah, that stuff must LOVE
alkalinity!! So I doused the wall with vinegar! No more white fluff,
to date...

PS.. I tell a lie. I just had a look and the white fluff is back with a
vengeance! I notice it is completely odourless, so perhaps it's not
vegetable matter at all, but rather some kind of mineral crystalline
growth.

Al