Vinca minor per square metre
I have a steep bank on three sides of my garage and I would like to stabilise the soil by planting vinca minor, possibly Gertrude Jekyll.
I estimate the area to be around 20 square metres and I can buy the plants in 9cm pots or, at a price premium, in 2 litre pots. Does one size have merit over the other? And how many small/larger plants should I order to cover this expanse of ground? I would be grateful for your opinions.
The top of the bank is ‘ungardened’ land for bonfires etc so it does not matter if the vinca spreads out from its allocated space.