Lichen, a combination of algae and fungi, grows naturally in gardens and surrounding areas. Although lichen is not debilitating to to plants or rocks that it grows on and around, gardeners often find it undesirable. Lichen can be removed for aesthetic purposes.
Mix water and glycerine in equal parts, then add enough clay particles to create a thick mixture.
Spread the mixture over the lichen and allow it to sit for five to 10 minutes. Then scrub it off with a hard-bristled brush.
Wash the surface with water.
Mix water and bleach in equal parts. Using gloves and a sponge, apply the mixture to the rock surface from which you removed the lichen. This will prevent lichen from growing there again.
Determine what type of lichen is growing in the garden before you remove it, as some types are rare and should not be removed. For example, Boreal Felt Lichen is extremely rare and grows in dark brownish-grey to bluish-green velvety fronds. All lichen types can be determined with the aid of online plant encyclopedias.