Why do I have rushes in my garden

Hi Proethean and welcome, as you are in a new build it is possible the soil has become completely compacted when the builders were working. Equally there may well be a load of rubbish and rubble underneath a thin skim of top soil.

Where we live when they start building they remove all the top soil and SELL IT once building is done they level everything with a JCB dress with an inch or so of top soil and that is it!

Try digging down and see what you find :-)

If there is nothing in garden that you want you can spray the whole lot with Roundup leave for a week or so and spray again. However, you will have to work on improving the fertility of the soil - with humus and compost... good luck you are on a new exciting garden path!

Don't know where you live in the UK but if you'd like more advice send me a PM.

Rushes grow on wet ground, so more than likely the ground is compacted hard underneath. You will need to spray it to kill the roots, but you also need to improve the drainage,