Understanding Toadstools in Your Newly Laid Lawn

Have you noticed small brown toadstools or mushrooms popping up in your recently laid lawn? It's a common occurrence that can be attributed to the biological processes taking place beneath the surface.

When turf is harvested and laid, damage is inevitably caused to the roots and other underground parts of the turf. Microscopic bacteria and fungi present in the soil then begin decomposing this dead and dying tissue. This natural process of biological decomposition is essential for breaking down organic matter in the turf and occurs throughout the garden.

While these fungi that feed on the dead material are usually too small to be visible, certain weather conditions can trigger their reproductive phase, leading to the emergence of small brown toadstools in the turf. The spores released from these toadstools serve a similar purpose to seeds, dispersing through the air and potentially finding new areas to grow.

In the case of newly laid turf, these spores will only grow if they find a suitable food source within the turf. Once the dead material has been fully decomposed, the toadstools will naturally disappear. It's unlikely that they will return in significant quantities once the conditions are no longer favourable.

Understanding the natural processes at play can help you appreciate the temporary presence of toadstools in your lawn and reassure you that they are simply a part of the ecosystem at work.

When do toadstools appear?

Toadstools typically make their appearance when the weather conditions are warm enough. When you water your newly laid turf, you create an ideal warm and moist environment for the fungus responsible for producing toadstools to thrive. Under suitable conditions, toadstools can start emerging a few days after the turf has been laid. They tend to grow rapidly and may stick around for a few weeks before disappearing. In some cases, there might be a second brief outbreak, especially when there is another spell of warm and moist weather. If the turf is laid during colder weather, the fungi will remain dormant until the temperature rises and the conditions become more favourable. If the decomposition process is not complete by the time winter arrives and the cold weather halts the fungi's growth, there is a possibility of more toadstools appearing the following year. However, it is uncommon for toadstools of this kind to reappear in the subsequent year.

Could Your Lawn Be Diseased?

When it comes to toadstools in your turf, the first concern that may come to mind is fairy ring disease, a serious issue for mature lawns. However, not all toadstools spell trouble. The small brown toadstools that appear in newly-laid turf are harmless and pose no long-term consequences.

If you spot toadstools of different colours, it's likely they are thriving on buried dead wood, such as tree roots. In this scenario, the toadstools will be directly above the decaying wood. Removing the wood can prevent the growth of fungi of this nature.

Are they poisonous?

Without accurate identification, it is difficult to determine if a specific toadstool is poisonous. It is advisable to keep small children away from them as they could be harmful if ingested in large quantities, similar to other garden substances.

Can they be treated? 

While there are no recommended fungicides in the UK for these toadstools, they do not harm the turf and are a natural and temporary occurrence. If concerned about children consuming them, the best approach is to remove the toadstools by mowing the affected area daily until they stop appearing. Breaking their stems can also help them dry out and disappear, as they are primarily water-based.