I have wild marjoram in a bed in my backyard, and it's taking over the entire bed, spreading into the lawn and coming up between the paving stones of the sidewalk.

I read something quite some time ago about controling a plants growing area by planting it in a pot in the ground, but can't recall if the bottom was to be cut out of the pot? Also, should the top of the pot be above ground level?

Also wondering how I can reduce the size of the plant now that it's spread.

Thanks in advance!