The effects of poor drainage on lawn
Author: Stefan Palm Date Posted: 8 July 2020
If you notice that pools of water hang around on the surface of your lawn after rain, then you may have a drainage problem. Poor drainage will almost certainly have a detrimental effect on how your lawn looks and performs during winter.
Winter is the time of year when you are most likely to experience drainage issues, mostly because, you guessed it, there is much more water around. Lawn areas that don’t drain properly quickly become waterlogged and that isn’t good news for your lawn. This can occur for many reasons but is more common where the soil is a heavy clay or where there are low points which naturally collect water.
The more waterlogged a soil becomes, the less oxygen is present in the soil. This results in your lawn being unable to breath which left untreated can ultimately cause the death of your lawn. A lack of oxygen in the soil is often referred to as anaerobic conditions which can also lead to the build up of gasses like carbon dioxide and ethylene which are not good for root growth.
When roots in the soil are waterlogged for long enough, they begin to recede and rot. The older blades of lawn will turn yellow and the entire stand will begin to thin out and look brown. You may even notice a rotten egg or sulphur type smell in the soil. It 's unlikely that your soil will remain waterlogged for long enough for the lawn to totally die but it can cause significant issues.
What can you do if you have a waterlogged soil?
If you notice that you have water on the soil surface for extended periods of time, I would advise you to consider ways of diverting that water away as there are very few plants that will tolerate waterlogged soils. Methods include coring, topdressing and introducing drains.
Coring can help divert water away from the surface. The deeper the core holes, the better. Once the coring is completed, lightly top dress (to fill the holes) with some coarse sand or gypsum. Be sure not to top dress heavily in winter - you shouldn't aim to bury any of the existing lawn.
If your drainage issues are more severe, you may need to consider installing a drain. There are many types of drains available on the market that will allow you to collect and divert water away to your storm water system such as ag-drain, strip drains and pit drains. If this is not possible, consider installing a soakage pit. This is where you dig a pit or hole in the low part of the lawn where water accumulates. Fill it with course rock or gravel, then put a 100mm layer of soil on top. Water will filter past the soil and into the pit where it can dissipate over time which keeps the water away from the surface roots.
Solving drainage issues can be difficult and solutions can be very tailored and unique to your circumstances. If you need any further help with drainage, give us a call on 8298 0555 or send me an email to firstname.lastname@example.org