Xref: news7 rec.gardens:218324

On Sat, 05 Apr 2003 15:42:38 +0000, Mike wrote:

Hello all -

I have outdoor carpet covering concrete steps, and have noticed a small
amount of moss growing between the steps (in the horizontal fold of the
carpet). This is growing on the uncovered portion of the steps.

I have found the "Moss Out" for structures at the lawn/garden store, but
am wondering if there is a non-chemical treatment solution (ie: vinegar,
etc?).

From my understanding, all moss out is made of is iron sulfate and
ferrous ammonium sulfate. These arn't terrible chemicals to be using as
long as there is no concrete around. Iron sulfate will stain concrete. The
only non-chemical answer I can think of is a pressure washer. Hose off the
moss and it will be gone for a while. Some folks like to use bleach water
(2 oz per gal) in a little spray bottle to help retard the moss from
coming back afterwards.
http://yard-works.netfirms.com