Sowing grass on old periwinkle bed
We'd like to extend our lawn into an area that used to be covered in periwinkle. Last autumn I ripped it all out though stopped short of a deep dig to get the roots out (the area is at least 2x6m and I couldn't face the task!),thinking I could cover it in the hope the periwinkle would eventually die off. Unfortunately this fell off the bottom of my to-do list and now there is not much time until we are able to sow a lawn. Does anyone have ideas for getting rid of the periwinkle in a non-back-breaking way? I am not a fan of weedkillers and would worry about the other plants that dot the area which I would like to keep! I suspect the answer might be just to dig or kill, but hopefully there is a less tiring/invasive solution!