Spider droppings can be removed from siding when the faeces is still soft using soap and water. When the droppings harden they are not as easy to remove. Oxygen bleach is a non-toxic green cleaner that comes in powder form and is mixed with water. The solution has an active ingredient which creates active ions which break down organic materials like spider droppings. Once the bleach has done its job the droppings can be rinsed from the siding.
Fill a mop bucket with a gallon of warm water and then dump in 170gr. of oxygen bleach powder. Stir the water for five minutes until the powder is dissolved using a stir stick.
Submerge a spray bottle into the solution and fill it up. Place the spray nozzle onto the bottle. Twist the nozzle until the solution sprays out in a semi-fine spray.
Squirt the solution on the areas where the spider droppings have accumulated and let it sit for five minutes. The solution will dissolve the droppings in that amount of time.
Scrub the area with a soft-bristle brush after the five minutes to further loosen the softened droppings.
Fill a mop bucket with warm water and 1 tsp of dish soap. Mix the soap into the water with a sponge.
Lift the soapy sponge up to the siding and rinse away the oxygen bleach and spider droppings. Rinse the area with a garden hose. Keep the garden hose pointed down toward the ground to avoid getting water in between the siding joints.
Work on the shady sides of the house to minimise evaporation. Oxygen bleach is an environment friendly cleaner and no special safety equipment is required for use. An insecticide can be used to kill off any spiders before cleaning commences.
Some spider bites can be deadly and so gloves, close-toed shoes, trousers and a long-sleeve shirt should be worn when working around bushes.