Nepeta 'Six Hills Giant' grouping advice

[Briony]

I am adding this to a border and would like to know how many I should buy. Would one plant suffice or do I need to buy three? Thanks.

[veggiechicken]

This might help https://www.rhs.org.uk/Plants/11491/...-Giant/Details
It probably depends on how much space you have and what sort of an impact you want.

[Briony]

Thanks. According to the link one plant might reach 1m squared so that would be all I need.