Take the 2-minute tour ×
Home Improvement Stack Exchange is a question and answer site for contractors and serious DIYers. It's 100% free, no registration required.

I've got a brick walkway that has parts that are in shade most of the day. Our winters are wet and cloudy and during these times it's not uncommon for the shady parts of the walkway to grow a fair amount of moss on the bricks and grout (see the photos below).

Come summertime, the moss dries out and dies and can be hosed off quite easily. However, I have family coming in for the Holidays and would like to remove the moss pre-emptively, as it's both unsightly and slippery.

Any advice/suggestions on how best to remove the moss? My first thought was to just get down on my knees and scrub it off, but my concern was that it would grow back in short order. Would using bleach or a bleach-like product have a more lasting effect, or would using such a harsh product outside where there is grass and plants nearby be an unwise move?

Finally, is there any preventative steps I can take to reduce the quantity of moss that grows during our wet season?

Brick walkway with moss, photo #1

Brick walkway with moss, photo #2

share|improve this question
    
I don't know how it would work on moss, and it's certainly not a persistent solution, but ordinary white vinegar is surprisingly effective at killing off weeds growing through driveway cracks. And as chemicals go, you can't beat it for safety. –  keshlam Sep 7 at 17:02

5 Answers 5

up vote 12 down vote accepted

My immediate vote is for a pressure washer. They are relatively cheap these days. Lacking that, a simple high pressure hose nozzle and a good stiff brush will do well too. Various oxidizing bleaches will also work, all of which will last for only a limited time.

To stop it from returning is difficult, since any moist, shady spot under a tree or bush is likely to grow moss and algae of this sort.

One idea is to remove the overhanging growth from the planters. Trim them back. This will help the brick pavers to dry out, and will reduce the tendency for unwanted growth.

Another idea is to get creative, and buy some zinc strips. Copper flashing might work too, but they sell zinc strips specifically for roofing applications, where moss and algae tends to grow on roofs. The elemental zinc leaches out (very slowly) when it rains, which in turn inhibits growth of the algae where it leaches out. So you could afix these strips to the bottom edges of your planter. Make it decorative and it should help, although I cannot assure it will work perfectly. At least this will inhibit the moss.

Another idea is to buy/make a few copper pots or planters. Place them decoratively right on top of the problem spots. As the copper leaches out from weathering over the years, it too will inhibit growth on the walkway, you not be a problem for larger plants in the area. If you cannot find a pot you like, you can make a planter from wood, but then wrap copper flashing around it, nailing it in place.

Be creative if you wish to inhibit the growth.

share|improve this answer
    
Thanks for the suggestions! Regarding overhanging growth, the problem isn't that, it's that these portions of the walkway are positioned next to the house on the north side, so it's in the shade due to the house most of the day. Can't very well trim back the house! :-) –  Scott Mitchell Dec 13 '10 at 16:58

I would try oxygen bleach, like Stainsolver.com. It is not harsh for grass and plants.

share|improve this answer
3  
I have to wonder, though, if oxygen bleach is not harsh for plants then how, exactly, is it going to kill off the moss? :-) –  Scott Mitchell Dec 14 '10 at 16:34

Powerwashing will certainly get rid of it, but that will not be a preventative measure.

share|improve this answer

After you power wash, use some water and dish detergent, don't rinse it off. We have mold problems here in BC and it is a deterrent that works. It doesn't get rid of it forever and will need to be repeated but it will slow down the development.

share|improve this answer

The best and safest method is Mouldex SEL20, an all natural control agent. Spray it on the affected area. It will last approx 12 months. It's not messy, it wont poison the environment and it's inexpensive. We have terracotta pots around a pool area and had moss and mildew growing on them, one spray and a light scrub with a brush and they look like new and that was a year ago. Photo available. Hope that helps.

share|improve this answer

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.