Waterlogged garden

Montyfangirl

Hi all. Need to sort the water logging by my existing hedge & where new planting will go. Someone has suggested a soakaway in the bag corner and a gravel drain along the existing hornbeam headhe run  is that the best route? We are starting work on it on Monday as a local labourer is free for the week. We will be planting new hedging along the back & moisture living plants in around the lawn  the lawn is going to be ripped up, soil treated & made smaller to allow for planting around it  any advise welcome  thanks Need to 

Montyfangirl

Sorry for typos! iPhone & chunky fingers issue! 😂

treehugger80

you need the biggest sump you can afford, dig it deep rather than wide and fill it with chunky rubble, cover it with a couple of layers of weed suppression membrane (just stops the soil getting back into it) and put 5-6 inches of soil on the top to level it out with the rest of your garden. You then run land drains into the sump

Montyfangirl

thanks tree hugger. do I need to work in horticultural grit too? the area is about 50m2 so looking expense if I need to use this!

Borderline

Good advice from Treehugger80. It's up to you if you want to put grit, but I don't think that works on large areas. But bark chip should be fine too. On soils like that, it's best to create tiered system. Tree, shrubs, and plenty of evergreen shrubs help. The more shrubs the more they take up the water. You have vast bare space, and lawns will always be soggy in winter if you have a clay-based soil. If you decide to keep the lawn, it's going to be a yearly program of spiking, raking moss and top-dressing.

Montyfangirl

thanks borderline, we are getting rid of quite a large amount of the lawn - imagine a two metre border all the way around the current boundary area (except the section adjacent to the patio by the patio doors), with a smaller turfed area inside, so that I can put planting in. 

Do you think I would be better off finding a water loving plant to put in that corner then. I looked at pumps and sumps and they are out of our price range so we are just going to have to make do with a nice big hole with rubble so long as the water table isn't too high - going to test with holes later.

Would the grit help for the planting I plan to put in - ie will it give it a better chance? Spent the whole of last year, scarifying, spiking and top dressing and have ended up with a completely mossy lawn again. I a trying to get dh to agree to tiny/no lawn but he's not keen.

Borderline

Don't be put off by puddles like that right now. Sometimes, it feels like it's just you going through poorly drained soiled in winter time, but in fact, many suffer similar problems to yours. Problem with Hornbeam shrubs, at this time of year, they become a skeletal structure, so it makes it really obvious at ground level how sodden it is. Any lawns on heavy soils will turn to a mud bath if trodden on. 

As mentioned before, if you keep any lawn, it's going to be a yearly cycle of aerating, scarifying and top-dressing. It's the type of task you would do if you had any other type of lawn to create even surface and uniform grass growth. Moss on lawns - that's something you have to accept will return. Moisture and lack of sun alone will cause moss. 

For me, I think your soil can slowly improve when you start throwing down compost and well rotted manure every year. I suggest twice a year in the beginning to help your soil. Try to wait until it's drier and warmer to do this. Turn the soil over and wait for the sun to dry it up a bit more, and the chuck loads of compost or similar and dig in again. When planting anything, mix in more compost. This cycle over the years will improve the conditions.

Evergreen shrubs are useful because once a canopy is formed, the shape of the shrub will minimise compaction from heavy down pours into the base area which allows the soil to slowly dry at the top but also encourage the roots to search deep down to get the water, and on heavy soils, it's ideal. The leaves take the hit and then they slowly roll down into the soil without causing compaction. The more dense you plant the better. Shrubs need water and as they mature, they will suck a lot of that surface water you now see.

Depending on how much sun you get there, a lot of shrubs can do well in that corner. 

Lizzie27

Hello,  Have you considered a pond in that corner? Or a boggy bed with water loving plants. Does the garden slope down to that area or is the whole site level? If the latter I'm afraid you might always have a water problem, in which case you could digging out more than one hole, filling it with rubble or gravel so the water drains away more easily.
Alternatively I wonder whether making the new lawn area slightly raised would help the grass survive better. You might also be better off waiting to do the work until the weather is dryer, on the grounds that working on very wet soil will make matters even worse.

Borderline

Looking at the photos, it’s not unusual to see puddles like that in winter. It’s worse due to the fact that Hornbeam can turn skeletal by February/March time.

If budget is your concern, wait until it’s a lot warmer and then turn the soil. Wait a few more days till it dries up further and the chuck loads of compost or similar on top. You must be generous. Mix that into the soil and continue to do the same at least twice a year for first few years. 

Planting in a tiered system of tree, shrubs and more shrubs especially evergreen shrubs will change your soil slowly. Apart from sucking up water from the soil when they mature, the dense canopy they create acts as a protection to the soil to limit compaction from torrential rain. The leaves catch the water and it slowly rolls downwards into the soil beneath. Deciduous shrubs will build up dead leaves that will rot down into the soil.

There are plenty of shrubs that will cope in your soils provided you plant when drier and you prepare the planting hole well.

The lawn work will be hard work. If you felt that last year’s work is hard, then a lawn is not for you. You will need to repeat the cycle of aerating, scarifying and moss removal. Then there’s the yearly top dress to create a new layer of suitable soil that helps minimise muddy soils, it may not give you the results straight away. 

Montyfangirl

thanks Borderline - that's all really helpful and makes total sense. The hornbeam was being strangled by ivy that was about 10 years old (according to neighbours who've been here longer than us) and the roots had extended into the lawn so we had to renovate the hedge and rip out the ivy. I guess the result was less leaf protection over the winter and less plant sucking up the water after we had rid of the ivy. 

I'm thinking I will plant some bog/wet shade plants in that area too.

I dont mind the work on the lawn, it's just disappointing to have it back to 90% grass by October and then back to 90% moss by March!

I've dug a few holes around the garden today and the ones in the lawn aren't that wet beneath the surface. The hole by the hornbeam is filled with about an inch of water after digging out so planting shrubs etc is going to be the way forward. I have pittosporum and coprosma hedging I need to get into the ground so I am going to start at the dry end of the garden and hope that the soil dries out a bit, the other end so we can finish off in the next few weeks.

Borderline

Hi Montyfangirl, good luck with it. I hope you are planting both Pittosporum and Croposma in quite dry areas because from my experience, both need quite free draining soils and sun. Soil preparation is key, spend the time to dig the soils deep down and work the surrounding soils with compost to create a loam based consistency.