Lichens are found in many places. It is a sign that the air is clean and we should actually be happy with it. But on tiles or roof tiles they can be quite unsightly. We have tips for removing it.
What are lichens?
Lichens can be recognized by fairly round, bubble gum-like spots. They form a very thin crust, mainly on rock or bark. They have a light, white or greenish color, but also come in brown, yellow or orange. It is a fungus that can only exist in combination with algae. This form of coexistence is called symbiosis. Lichens grow in moist places and they are not harmful. However, they can make a surface extra smooth. Which, for example, is not desirable in the case of a terrace.
Do not do this to remove lichens
Household products are not intended for outdoor use. They may seem harmless, but they are harmful to the environment and organisms that live in the soil. For example, vinegar should not be used in the garden to remove weeds or algae, and this also applies to lichens. The same is the case for baking soda and bleach.
Also read: Sustainable removal of green deposits and moss in the garden: do not use cleaning vinegar
Remove lichens with a high-pressure cleaner
A relatively easy way to remove lichens is with a high-pressure cleaner. However, it is important that the surface is resistant to this. Otherwise it may become damaged or porous. Which in turn can ensure that algae and lichens grow back extra quickly. There are also special attachments available that make circular movements, specifically intended for terraces.
Cleaner against green deposits and lichens
A biological agent against green deposits and lichens is also effective. In addition to tiles, this can usually also be used on roofs, walls and gravestones, for example. Use a brush or stiff broom to brush in the product and follow the instructions on the packaging. Such a remedy usually continues to work for some time, so you are freed from it for a longer period of time.
Lichens on trees and shrubs
Lichens can also occur on trees and shrubs. However, they are not harmful and it is best to leave them alone. Otherwise you risk damaging the branches or bark. It may be a sign that the tree or shrub in question is in a place that is too humid. By thinning it out slightly by pruning, more light and air passes through the branches and the effect is less noticeable.
If the above methods fail to remove the lichens, they have now penetrated too deeply into the subsoil. The spots that can be seen on the surface are the so-called lime efflorescence. The lichens themselves may have moved deep into the subsurface. In that case, a professional may still be able to help, but otherwise there is no other option than to leave them alone. Or in the case of tiles, for example, replace them in due course.
On the Garden & Balcony overview page you will also find many more tips and advice for garden and balcony fun. From advice on the care of garden plants to practical tips on pruning and landscaping.
(Source: archive, Telegraaf, De Terraskoning, Appeltern Adventure Gardens, ilovemygarden, Almere this week. Photos: Shutterstock)