Vinca die-back

Many of my vinca ground-cover plants are dying back. These plants have been healthy for many years. Symptoms include: black stem, yellowing leaves that turn brown and fall off. I am hoping there is a way to reduce the spread.…

Tarping invasive plants

I would like to tarp lily of the valley and periwinkle. Can I do this starting in August and remove the tarp in April? Thank you,…