How to deal with a waterlogged garden

What to do when heavy rain floods your garden

Wet weather is in abundance at the moment, with October being the wettest since 2005, and November seeing some of the heaviest rainfall for decades (not to mention the summer, which was the wettest in over 100 years!). While rainfall is usually celebrated by gardeners, too much of it can saturate and waterlog a lawn, causing fine grasses to turn yellow and die out. Thankfully, there are several things you can do to help prevent waterlogging and ensure a vibrant, healthy garden all year round.

What is a waterlogged lawn?

A waterlogged lawn is one where water sits on the surface and drains away slowly or not at all. It is most likely in areas which have clay or heavily compacted soils, but can also be present where soil has not been properly prepared before turfing or seeding. Easy to spot, waterlogged lawns will either have highly visible patches of water or soil-coloured puddles, or feel very squelchy underfoot.

What problems can it cause?

Lichens, algae and liverworts thrive in damp conditions, and can grow rapidly on lawns which are poorly drained or those which have not been aerated. Moss also favours damp environments (particularly where there is shade and acidic soil), and rush can seed itself to form tussocks. Fine lawn grasses on the other hand will die in such conditions, as the roots drown in airless, saturated soil.

How to deal with a waterlogged lawn

Dealing with a waterlogged lawn

If you’re facing a waterlogged garden, the first thing to do is avoid any unnecessary walking on it, as this will only compact the soil further. It’s best to approach the problem once excess water has drained away, however if doesn’t go within a day or so (assuming there is no further heavy rain during that period), try sweeping the sitting water off the lawn and into beds.

Aerating soil should be the first task on your list when dealing with a waterlogged lawn, and this can be achieved by shallow pricking the lawn with a slitter(approx. 1 inch), or using a deep spiking tool (such as a garden fork or hollow tiner) to punctuate holes 4-6 inches deep. These holes should then be filled with free-draining material, such as horticultural sand or top dressing, to allow surface water to drain to less compacted layers of soil.

Once you’ve dealt with the immediate problem, it’s important to diarise spiking every few years (ideally in autumn) to ensure that the problem remains controlled.

Give your lawn the best chance

With winter fast approaching, it’s important to treat damp soils and dead patches of grass with moss killer as soon as possible, as these areas can quickly become breeding grounds for moss. Applying a quality fertiliser to your grass in spring will then help it to recover from any winter damage, and encourage better growth in the root system, increasing its ability to survive flooding (and drought!).  Using a phosphorus-rich lawn feed in the autumn will help to reinforce these actions and prepare your lawn for the winter.

If you find that waterlogging still persists – perhaps because you are in an area with clay soil – it may be worth investing in a drainage system, or replacing the lawn with a new one. In the latter case, ensure that soil is properly aerated before laying 2 inches of sand, followed by a layer of nutrient-rich topsoil. Finish this with a high-quality turf, such as our Premium Grade Turf, and remember to follow the guidance provided to keep your lawn in the best condition possible.

Prevent your garden from becoming waterlogged

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