There are a number of causes that can lead to waterlogging. These include:
- Waterlogging is caused when water sits on the soil surface and drains slowly, or fails to drain at all. Roots drown as the water excludes air from the soil
- Poor preparation of the soil before turfing or seeding of new lawns can also lead to poor drainage and waterlogging
- Waterlogging is more likely to be a problem on clay soils, or soils that are heavily compacted
There are a number of associated problems that can appear when a lawn lies wet for short to long periods:
- Damp conditions encourage algae, lichens and liverworts on lawns. This includes bubble-like Nostoc algae and dog lichen. They both flourishes in badly-drained lawns but can develop wherever the aeration is poor, and may, therefore, appear on well-drained turf if the surface has become compacted and is inclined to remain damp after rain. It is also favoured by shaded conditions and poor soil fertility and so is frequently found on turf beneath trees.
- Moss is a common sight where conditions are damp, but particularly if there is shade and a low pH (acid)
- Clumps of rush may seed themselves, forming tussocks. See our weed control profile for more detail.
- It is worth noting that patches of dead grass where the soil proves very difficult to re-wet can be caused by a fungal problem: dry patch