Beautiful but deadly, moss & mould

Moss is a fascinating plant, there are over 25,000 species, the earliest of which date back at least 450 million years. Moss has survived and thrived through a range of drastic climate changes, it can grow where nothing else can.

In hot environments like prairies or deserts, one way that mosses tolerate heat is by becoming dormant. When they’re dried they can survive heat much better than when they’re hydrated. Moss and Lichen may dry out and appear dead in the summertime, but they will be back for the winter

In 2014 British scientists successfully revived moss that had been frozen under Antarctic ice for 1500 years, with nothing but an incubator.

Sphagnum moss was used in some places during World War II to dress wounds and lessen blood loss for the injured. These moss-bandages not only absorbed very effectively, but even soothed wounds – attributed to the mosses anti-bacterial properties.

So… Moss is sounding really cool now, right?

That’s because it is cool… when its growing where it belongs. Mosses have plenty of benefits in the natural environment. They provide a nutrient dense food for a range of animals, and can even encourage the growth of other plants by protecting their roots from high temperatures. When moss is present where its not welcome, such as concrete, roofs, decks, outdoor furniture etc , it can be a very dangerous hazard and an unsightly addition to your property.

Ok, so it looks bad! However, so do my weeds in the garden and I just ignore those. Why bother with my roof of all things?

While moss can look unpleasant on your roof, it can also cause structural damage, clog your drainage system, and dramatically shorten the expected lifespan of your roof. The structural damage from moss and lichen can be severe;  Both of these plants start degrading the underlying structure. Moss is well known for its ability to absorb water, when the weather turns cold this damp moss may turn into frozen or frosted moss, water expands when it freezes and can create a myriad of problems for your roof including causing your roof shingles to bend, warp, and even separate from each other over time. When un-frozen and simply wet, the moisture can create rot and provide a suitable environment for mould to grow.

Lichen obtains nutrients from its contact with the air, as well as from the surface on whence it grows. Lichen sourcing nutrients from your roof will over time degrade the roof material. This is particularly severe on many types of roof, including – asphalt shingles, roll roofing, wood shingle roofs, wood shake roofs. Lichen, like moss, can also trap water and freeze. Possibly the most devastating effect of lichen is cause by poor removal methods. Lichen is incredibly hardy and therefore very stubborn to remove,  it has a very strong grip on wherever it is rooted and so requires rigorous scrubbing to remove. This is not only very time consuming, but can cause more damage to the surface than the growth itself.

Due to the gravity of the problems cause by these growths,  your homeowner’s insurance rates could increase if it’s left untreated. Insurance does not cover faults in design or deterioration as this is not an insurable risk. If you have moss, mould and lichen growing on your roof you are more susceptible to damage occurring. Say your growth problem causes the shingles to separate, allowing water to enter the home and damage your carpet. Your carpet damage should be covered, as this is resulting damage of a fault at your house, but the repair of the fault is not covered as this was due to deterioration not properly maintained. (source: FAQ’s section –

Your home insurance could be the least of your worries, dangerous growth is a massive catalyst of accidents 

In 2011, Moss was the cause of 7,000 fall-related ACC claims and prompted a public service announcement about the hazard via ACC’s Home Safety Action Week 2012. John Beaglehole, ACC general manager of insurance and prevention services, stated there are plenty of ways to defuse the hazard. He suggested water blasting, scrubbing or spraying mossy areas with moss removal products; cutting trees and shrubs back to prevent the shady conditions that moss thrives in; and building new decks with grooved timber for grip.

Not everybody has the cash to spring on a new deck, and water blasting seldom truly fixes the problem – moss and mold are very resistant and, most often, grow right back. Worse than a poor success rate, water blasting can actually do more harm than good, blowing high pressure water into building materials or openings can create costly, hidden damage, even mold contamination.


That’s where Spray & Go comes in.

Our specially formulated moss and mould treatment has been created and manufactured right here in New Zealand, and uses proven and effective ingredients to get the job done.

Its safe to use on exterior surfaces and can be used without having to water blast or scrub the treated surface

Simply mix 1 part Spray & Go to 10 parts water into your handheld pressure sprayer, backpack sprayer or commercial sprayer . Every 5L pack yields 50L of ready product, similar products yeild only 30L of ready product. Picking a cool and dry day for application is crucial to producing the best results, applying the product during the evening is beneficial as the evaporation at this time will be minimal – meaning your surface stays wet for longer.

After your initial application, it’s important to keep up the maintenance – results will appear even sooner as the surface has been previously treated. Spot treating at the first sign of regrowth stops the hazard from coming back, and makes your product go further.


  1. Choose a cool, dry day to apply the product –  Rain will dilute the product further than recommended, you should aim for at least 3hrs of dry weather after spraying.
  2. Shake well before use.
  3. Mix 1 part Spray & Go Commercial with 10 parts of water.
  4. For heavily contaminated areas it may be necessary to re-spray again once the initial application dries.
  5. Application areas may become slippery when wet. Avoid areas until dry.


  • Lichen has a crusty almost concrete-like texture, making it more difficult to remove from outdoor surfaces, For greatest and swiftest results, spot spray the lichen as best as possible – This will help in softening its outer shell. After spot treating, wait about 10-15 minutes before treating the entire area as usual.
  • If the product is being applied to the roof whence water is collected from , we advise allowing a heavy rain before reconnecting any water supply. You may also drench the roof with a hose, for approximately 45minutes.
  • Sometimes you may find the moss shows discoloration after treatment, this is a good sign as the moss is dying.
  • Black mould or fungi can be particularly stubborn. Once treated with wet and forget it will dead, but it will take an additional few weeks for it to gradually weather away. You may wish to speed this process up by scrubbing with a stiff bristled broom, but it is not necessary.
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