Last autumn  I decided that I had to do something about my 150 M2 lawn which comprised of about 20% grass, 60% weeds and 20% bare ground. In addition, the lawn was very uneven.
I spayed roundup on the lawn in October and within two weeks everything looked dead. I left it until spring then tried to rake out the dead vegetation, but I was not very successful. I then sprayed everything again, and left it for three weeks. I bought several cubic metres of top soil which I spread to completely cover the dead vegetation and to level the ground. I then grass seeded using 40gms / M2.
I watered regularly, and within two weeks the ground started to turn green. It soon became evident that it was not grass that was coming through but some plant which was extremely green. With hindsight, I should have found out then what was growing and sprayed roundup again to kill it, but summer was approaching and what had grown looked nice when cut short.
As the summer progressed and after rain, it grew so very, very quickly and retained so much water that when cutting I slide all over the place. I have now found out that what I have in place of grass is purslane.
Having now researched it it would appear difficult to remove. I am proposing to spray with a high concentration of roundup this month, wait two or three weeks and spray again. The questions I have are:
After the initial spray and when everything appears to have died, should I remove all the dead plants or leave it as it should eventually rot.
If I have to remove it then it will need to rotivate the entire area as 150 M2 is too big an area to pull up the dead plants, and I really want to avoid this.
I still have a few metres of topsoil stored in the garden, and although there is no sign of the purslane in the stockpile, I assume it must be there because I can think of no other way it grew instead of the grass seed I planted.
If I can leave the dead purslane do I need to cover it with more topsoil because the ground in now nicely level and I have already expressed above my concern at spreading topsoil from my stockpile.
Many thanks in anticipation of some replies