Help with garden boarders

[Sm1308]

Hi. Need some help with my garden borders. I live in a new build and the soil is absolutely awful. Lots of clay but so waterlogged.
last month i spent ages digging out the grass along all the sides and put sleepers around them all. I planted plants such as evergreens, lavender, hydrangea and shrubs. However none of them are doing well. Ive tried plant food and adding compost to the top. They all seem to be dying. Any ideas on how i can gix this? Am i best to make my sleepers higher and have raised beds, dig out as much soil as possible and fill with compost/top soil. Or will i never drain properly and just re turf and have pots?

"Lots of clay but so waterlogged."

Another OP started a thread recently and she had a similar problem.

https://www.mumsnet.com/talk/gardening/5132634-new-build-garden-all-help-needed

She said:

"And horrible clay underneath which means if it rains for 10 mins you can't step on it for 24 hours (even my little dogs have to tip toe over it to pee). In proper rain it can be unusable for days. In the long term we'll get it sorted but for now we're stuck with this useless lawn."

I mentioned on that thread that a French drain might help. This is something that you can do yourself. There's a youtube video here showing how to do it:

and also some detail here about what a French drain actually is:

https://www.homebuilding.co.uk/advice/what-is-a-french-drain

"Am i best to make my sleepers higher and have raised beds"

This is certainly another possible way of dealing with things if the ground is totally waterlogged.

Another youtube video from that same channel about doing raised beds yourself.

My precious garden was just as you describe, even grass couldn't grow and it became a muddy mess. In the end we built a long raised bed in an L shape and planted it all up. If you want to have a lawn, unfortunately, you will probably need to dig down and remove a lot of the clay and replace it with new topsoil.

I think take 12 months to not think about plants but work on the soil itself. Only then consider plants that will be happiest in the soil you have. Lavender, for example, belongs on Mediterranean hillsides. Find something else instead.

https://www.abc.net.au/gardening/how-to/clay-soil/9437326

https://www.rhs.org.uk/soil-composts-mulches/clay-soils

www.rhs.org.uk/search?query=Clay&tabOrder=.%2Findex.html%2Clinks%2CadviceGuidesVideo%2Cfaqs%2Cgardens%2Cmembership%2Cplants%2CshowsEvents&facetFilters=%7B%7D&filters=%7B%7D&referrerPageUrl=https%3A%2F%2Fwww.rhs.org.uk%2F&verticalUrl=adviceGuidesVideoNew.html

Do you have room for a small tree OP? They can really help with absorbing a lot of the moisture & reducing flooding.
Otherwise you need to improve the soil; raise it or plant for the conditions - bearing in mind location, orientation, moisture levels, etc

Clay is grim to work with and improve, though nutrient rich! Raised beds with topsoil and substrate are you best bet for lower maintenance. They can look very lush and a mixture of creeping and hanging plants like campanula or nasturtiums (which will self seed though) can soften up hard edges if you prefer a more natural look. Stepping stones in the lawn for walking on would stop it getting compacted.