You're right about the pot-in-ground thing. Mint will send their roots down quite some distance - out through those drainage holes is not a problem for it!

I am not familiar with Bermuda grass, but I know that mint has a yearning to take over the entire planet. I've had mint grow from a garden bed, across and under an expanse of lawn, under a concrete driveway wide enough for two large vehicles, and into my neighbour's yard. Goodness knows how far it travelled from there!

There isn't much you can do to stop mint from spreading, so you'll have to go for a really large pot. In fact, think about getting one of those kiddies' plastic swimming pools, or sand pits, filling it with dirt, and using that as a pot? It will need drainage holes punched into it, but you can always line it with weed-mat before adding the soil.

You'll need one of these for each kind of mint you have. Don't put any two together.

Here's a link for some of the past threads on how mint spreads. I'm sure there will be plenty of suggestions and opinions for you there!

One thing that I find to be very true is that people in different geographic areas, different climates, different soils, and different growing conditions all see differences in how "invasive" or how much a plant spreads.

Mint spreads for me but it is nothing that I have to "dig up my entire garden" to control. But then I have heavy clay soil and snowy, freezing winters and I suspect that has something to do with that. I also harvest anything down to the roots that I don't want growing where it is. Judicious harvesting can help to check a plant's wild nature.

FataMorgana

Here is a link that might be useful: GardenWeb - Herbs: Mint Spreading

Thanks to both of you for the info/advice. I have no room for a kid's swimming pool, and barely enough room for a couple large pots for growing peppers and spacemaster cukes, so I'll see what I come up with. I didn't know mint could cross a 2 car driveway...I'll take precautions before planting! Maybe heavy harvesting and competition with bermuda will keep the mint in check.

Also, I can grow both Peppermint and Chocolate mint together, because both are varieties of peppermint which is sterile and won't drop mixed-up seeds. But I might not grow the two too close together, or all the shoots will become intermingled and would make sorting a hassle...

I grow my mints in 15 inch pots with a hole in the bottom for drainage. Put the pots up on something like a cement block to prevent roots extending into the soil. I have tried air pruning but the mint plant just extended a runner toward the ground.

I must admit I am tempted to put it in the ground. I have a half-shady spot selected at the end of my vegetable garden that's got some bermuda invasion going on. I might try excavating the area, putting in a plastic liner, and filling it up again. If I keep the mint pruned hard (harvested down to near ground level) I might be able to keep it under control.

NOT a good idea! Keeping the mint pruned hard will only encourage those underground runners to work even harder.

Just choose the largest pot you can manage, and be prepared to regularly divide and repot, as it will become potbound very quickly.

Don't put the 2 mints together. Even though they won't cross-pollinate, the flavour of one will out-compete the other. My guess is that the peppermint will win over the chocolate mint.

Five gallon buckets with the bottoms cut out are usually the most sucessful containment method. Sink the buckets with 6 inches of it showing. Don't crowd the bucket. Daisy is right about pruning, but you do need to get rid of the flowers. Some animals will chomp the tops off and scatter them. And there will be mutations if you keep any varieties too close together even if peppermint is sterile. Sandy

Thanks for the advice, I guess I WON'T use hard pruning as a method of controlling growth.

Might try the 5gal bucket idea. I'll prob. want more peppermint than chocolate mint, so I'll put the p.mint in the ground/5gal bucket, and the choc mint will go in a regular container.

How deep is a 5 gallon bucket? If it's less than 1 metre deep, forget it. Those roots can travel deeply as well as far and wide. That mint I told you about that travelled under the driveway etc came from a garden bed, in which I'd inserted solid barriers vertically under the soil - and they were 1 metre deep all round. I kid you not. I knew a lot about mint, and had taken great pains to see that no above-ground runners escaped confinement.

Do NOT underestimate the travelling capabilities of mint!

My peppermint is only a year old, but the "pot buried in the ground" approach worked well for me. At one point mid season, I noticed that it was getting pot bound, so I pulled up the pot and re-potted into something larger. I'm pretty sure that if I hadn't re-potted around that time, the runners would have escaped.

So, if you take the pot-in-ground approach, I recommend that you don't just do that and ignore it. Keep an eye on it, and keep control of the runners.

Hi. I need some advise regarding mint. I put in flagstone patio and had originally filled spaces with crushed granite. Do not like it so am in the process of digging that up. Would like to replace the cg with groundcover, either thyme or corsican mint. Really love the mint but am not sure if it is the best choice. Am in OK, have Eastern exposure (sun in the am-shade in the pm). Any suggestions? Much appreciated. Tara

Maybe I could grow small crops in above-ground containers, and then the main big crops can be grown down by a creek! With the concern about eroding creek banks in our area, I wonder if mint would be considered beneficial growing on the bank, since the roots apparently go very deep and would help hold the banks together. Or maybe it would be too invasive.

About a year or so ago, I was in a small creek with a large rotting log sitting in the middle of the bed. There was spearmint growing out of the log. I might want to go down there sometime and see if it's still there.