How to end the algae invasion on glass, paths and drives.

GPI

How to end the algae invasion on glass, paths and drives.

Algae are the much-maligned green slimes found on ponds and as a greenish scum on paths and drives. Most of us regard this substance as just another form of dirt, which has to be cleaned up and removed. You may be surprised to know then, that algae is actually a living garden plant, albeit a stem-less and non-flowering specimen.

Over the course of a damp winter, disgusting greyish-green algae often builds up on the inside glass of our garden sheds, glasshouses and across the film on our polytunnels. If you find some of this slightly powdery scum builds up, you can easily wipe it off the glass with a mild detergent, whereas on polytunnels you must omit the mild detergent, only wiping the plastic with warm soapy water. One of the best solutions to this form of algae growth is to trim back any surrounding planting to allow as much light as possible to enter, creating a bright situation, which the scum despises. Also, try leaving the doors and windows of these structures open for a few hours each week to prevent the build up of stagnant air.

The “Jeyes fluid” solution.
Damp shade is again a big factor where algae and their partners in crime, the mosses, seek to coat our paths and quite dangerously our garden steps with their slippery greenness. Reducing shade and dampness by increasing the areas access to sunlight will greatly cut down on algae/moss growth. The application of a “Jeyes fluid” solution to slippery paths with a fine rose watering can is a time tested method of algae and moss control here in Ireland. Rope in a helper to drench the paths and steps with the mixture, while you vigorously work in the solution with a stiff bristled brush.

Bluestone is oldschool.
Another effective and more economical way to remove algae is to apply a copper sulphate solution (commonly known as bluestone); this has a residual effect that prevents regrowth for up to several years after treatment. Mix copper sulphate or "bluestone" at a rate of 5 grams to 10 litres of water in a plastic watering can with a fine rose. On a dry day water it on then brush it in, leaving it around 3 weeks to act on the algae. A few days after the growth turns brown, brush again with a stiff bristled brush and “hey presto”, an algae/moss free area. When applying any algae or moss control solution remember to avoid drift onto surrounding lawns, plants and vehicles. Use protection equipment when applying chemicals including a mask with a dust cartridge, safety goggles and impervious gloves with overalls
Take care, apply all chemicals according to the manufacturer’s instructions and heed those safety warnings.