A wet lawn - a pragmatic approach to lawn drainage
We get a lot of emails and also comments from lawn owners seeking advice on their lawns and this lawn advice blog is our initial technical outlet and first prot of call for lawn owners seeking lawn advice.
There are over 550 technical articles to help you with your lawn so please do use the lawn advice blog search facility before posting a comment or emailing us as you are going to find the answer to the most common lawn problems from the confort of your armchair or desk.
When you cannot find the answer, please feel free to post a comment and this will find us and we can respond on this blog or privately. The question and answers email below is a good example of the help we provided to one recent lawn owner who had posted a comment about a soggy lawn -
Answer - One problem with water on a lawn, it is coming from rain or run off from a terrace or patio or driveway or from next door if your neighbours house/garden is higher than yours. Can you stop any additional water getting across the lawn, like installing a catchment drain/pipe work along side a terrace, path etc. You get the idea. All drainage systems need one important thing - an outfall so a storm drain or ditch is ideal.
We have had loads of rain recently and it takes a while for what's known as the gravitational water to be pulled from the surface following rainfall. You were wise to dig a pilot hole so about a border spade wide/deep etc to see if you had any capillary water coming up from a possible high water table. Dig a few holes and then put a measured amount of water like one litre into the hole and see if it takes a long time to drain away. Time it infact and see if it varies across the lawn and other pilot holes. If the water drains away okay then the soil is capable of natural drainage. If not, dig a deeper hole, so two spade spit deep and repeat the fill it with water bit. Does it drain better or not. Sometimes it is the surface that has 'capped off' restricting water getting from the top to the soil below.
Have you changed your garden at all like removed trees or anything else that may alter the flow of water around the garden? Have your neighbours? Do you have a natural spring? Is it always wet even in the dry weather. Having desirable turf grasses will help too as the natural evaporation from the turf plants has quite a drying effect.
If you have tried all the above and the lawn is still wet then and you have had a good look at the soil profile/root zone and a little deeper, then drainage may be the only solution. One cheap deep aeration concept is hire a Kango Breaking Hammer from a hire shop with the largest and deepest metal bit you can, make holes in the lawn at say 0.5 metre centres and using a crude funnel out of a fizzy drinks bottle back fill the holes you have made with 10mm pea gravel almost to the top. Use a string line to make a grid of the lawn when making the holes. Cheaper than a full drainage system and it may work open the soil. Surface aeration with a mechanical aerator with a solid tine so 4-5 inches deep may help too.
Question 2 - Thank you. I have already made 2ft holes in a grid like pattern in one section of the garden . I used a hand held auger to do this and back filled with pea shingle and it hasn't improved that section? However, I did this in between very rainy weathers but how long should it take to notice a significant difference after doing any of the ideas you mentioned? Many thanks for the quick reply.
Answer 2 - Asess it when we get a few days of no rain. We do formal lawn consultations that may be booked via The Lawn Shop.
We have mentioned a concept called Sub Terrain Aeration in the past - this is when a deep metal probe is inserted into the soil and compressed air is fired through the sub soil to create natural deep drainage channels. It solves the most severe compaction and poor drainage problems in all sorts of scenarios.