First off, here is the plant.

I would have taken pictures of my own patch but I have been too busy murdering the majority of it.

Do not plant it. Do not. I planted a one-gallon container of the stuff several years ago. Knew nothing about it. Last year I sorta lazily tried to dig a bunch of it out, as it had spread to about a 10 foot area. This year that area was much bigger.

I have been digging up fairly large azaleas just to get this crap out of the roots. I might keep a start of it in a buried tree pot with the bottom cut out, since it IS very pretty, but none will remain where it can spread. It has rhizomes similar to johnson grass, bermuda, etc. Very soft and easy to break and each piece can make a new plant. Gah. It is horrible. Roundup seemed to do nothing to it.

I have a 30 gallon trash can FULL of root pieces and leaves from this stuff. I spent about eight hours on it earlier this week, four hours another day, and about six hours today. I am probably half done. DO NOT PLANT IT. NO NO NO NO NO. DO NOT.

Demonic plant.

When I bought the house I'm in now it had be ignored for years and empty for a year and most of the front yard was mint. The stuff was everywhere and it took three years to get rid of it. I still can't eat mint sauce.

Holy shit. That sounds epic. I have some Bishop's Weed by my front door that I am half-heartedly battling with. I haven't launched a serious assault yet.

Wow, I had a mint plant show up last summer and I liked the smell of the leaves, so I was going to let them spread. Should I fear them?

Mint is evil evil evil. Impossible to get rid of. I have the scars to prove it.

Mints (most anyway) can be moderately invasive as they will spread until you stop them either by digging up excess growth, killing it, or putting a barrier in the soil to stop the mint from spreading. BUT it is much easier to dig up or simply to spray and kill off than this crap I am fighting. I have spearmint, peppermint, pineapple mint, apple mint, ginger mint, chocolate mint, and uh... I forget what else at the moment. All spread, the spearmint and peppermint are the worst, but not nightmarishly so unless you just ignore them for years and years like the previous owners of the house mentioned above. I kinda like letting some of my mint escape into the yard, mowing it keeps it from spreading too much out of bounds and it smells nice. WHen you cut a little. I would HATE to mow a yard full of it.