A Sacred Grove must be at least on a 250 sq. ft area. This is simply because a grove must have some space for it to grow, live and breathe. Only then will it become a little spot of biodiversity with room for a small population of birds, animals and insects.
A Sacred Grove can be anywhere. Location doesn’t matter. What matters is its status as a patch of green that makes some contribution to the well being of life on this planet however small.