Talk:Horticulture/Vinca

It is amusing to see that vinca is considered an invasive weed in parts of the U.S., as I have a customer with a large hillside vinca groundcover that has been ailing over the past two years. It is an important plant in her landscape as it provides erosion control and is (or at least has been) relatively easy to care for.

I am wondering what soil conditions and annual rainfall is normative in its native range. What sort of soil type, soil pH, and irrigation regimen should I expect vinca to flourish under?