You probably don't have to go to that extreme measure to contain the mint.
Usually any physical barrier that's @ 3-4" above and below ground will do
the trick. Don't, however, forget to check on the mint from time to time to
make sure it hasn't crept above or below the barrier.

Suzy, Zone 5, Wisconsin


"Virgil Caine" wrote in message
...
I love this mint plant. It has grown like crazy. However, it is very
invasive and is shooting roots into neighboring plants and sprouting
everywhere and all around.
I learnt that it should be contained by planting in space with no-out. I
am thinking of planting it in an old Fish tank and bury the fish tank into
the ground. I inherited this fish tank (1.5 ft deep X 4 ft wide X 2 ft
high) when we
moved into this old house. Has anyone done this? What are the problems if
I do this?