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removing algae/mold from white stained cedar fence

How can I remove green algae/mold from my fence without damaging the underplanting of perennials? I need to clean it up well before restaining!

Re: removing algae/mold from white stained cedar fence

Wash with water and some Murphy's Oil Soap. Then brush the fence with a mixture of 40% Boric Acid, 60% Borax mixed with water. If you have some old antifreeze leftover from a drain and refill of our cars radiator, you can dilute that to about 33% concentration and mix about 2 lbs of the Boric Acid and Borax solution per gallon. Otherwise its about 1.5 lbs/gal.

Re: removing algae/mold from white stained cedar fence


Go to Home Depot and buy a quart of "Jomax". A quart bottle is mixed with 3 quarts of household bleach and 4 gallons of water to give you 5 gallons of solution. Jomax is a mixture of detergent, a bleach activator, and an additional mildecide. The bottle sells for under $10.

I have used this product for over 20 years. The mildew will disappear before your eyes. I have never had my grass or foundation plants stunted or killed with Jomax. If you are particularly concerned about your plants, temporarily throw a piece of lightweight plastic over them until you have pasted by.
Personally, I take no effort to protect plants other than try not to hit them directly with the spray. I fill the Jomax solution in my garden sprayer and thoroughly wet the surface. Make sure you rinse your garden sprayer out if you have used weed and vegetation killers recently. You should try to keep the surface wet with the solution for about 5 minutes, followed by a vigorous rinse with a garden hose or power washer with a wide spread tip. The rinse water will also aid in rinsing off the leaves of the plants which will also lessen any chance of damage to the plants.

I live in the Oregon where mildew and algae could be the State plants. I use Jomax to clean my wood fencing, gable shingles and also on my concrete patio and driveway. It is a great product at a reasonable cost. The gallon size jug of Jomax sells for under $20 and is even a better value.

I have over 200 feet of six foot tall cedar fencing which has no stain or protector on it at all. I Jomax it every year and it keeps it from turning black. Every other year, I bleach it out with an oxalic acid containing fence cleaner and it keeps it looking, if not new, bright and natural looking.

Re: removing algae/mold from white stained cedar fence

Ditto on the Jomax,,,,,Great product

Re: removing algae/mold from white stained cedar fence

Thank you so much! I can't tell you how much I appreciate that you took the time to help me with this dilemma. It even occurred to me to just replace the fence , rather than risk damage to the many hundreds of dollars worth of landscaping along the base. I'm in Ma. and have SEVERAL inches of snow on the ground right now. Maybe I'll try an area on a warm day, before the snow melts, for even more protection and see how it goes.
Anyone want to come help????

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