BOG PLANTS -- WHICH ONES TEND TO "TAKE OVER" AND BE A PROBLEM?

[Mmathis]

There are a few garden plants I will forever stay away from -- the ones that are so invasive that they "take over" if you let your guard down. And I'm not a gardener who stays on top of things, so it's not hard for that to happen in my yard.

So, I'll soon be embarking on on building my first bog! Would REALLY LOVE to stay away from plants with a history of being invasive as bog plants. I kinda like the plants that will grow well, but grow & spread gradually.

Your input is greatly appreciated, guys, so which ones can quickly become problems?

 

[Waterbug]

Define "quickly".

In general I'd say the larger the plant the slower they spread. Duckweed (if standing water) is very fast. Pennywort fast. Canna slower. Marshmallow very slow. Some are more covert than others. Horsetail Reed can expand beneath the surface and then start popping up. Mint can be like that.

There's a Catch-22. The same plant in one bog may not spread, may even die, while in another take over in a month. So it's not really possible to categorize all pond plants.

There's a couple of ways to approach this issue. Let nature landscape your pond and let a plant take over, and be happy. If you want control you can contain plants in containers buried in the bog gravel. That will slow down many spreading plants especially if water i kept 3-6" below the top of the gravel.

No matter what you do your definition of "quickly" is important. If you remove all plants once a year, divide and replant you generally won't have a problem depending on your definition of invasive. Each year that passes roots get more and more dense which makes any gardening in the bog harder and harder. Containers can bulge after a year and split open after 2 years.

 

[CountryEscape]

Great info, Waterbug.
If you're worried about plants that grow fast and can take over, as he said, stay away from Pennywart. Also, water clover is a very fast grower. I'll be giving away both of those this spring when I get in there and pull probably 90% of them out. Dwarf cattails also spread, not quite as fast, but can be a problem, as they are hard to pull up, deep roots. I will also have them to give away starts of. LOL The plants I really like are irises, which tend to not spread as quickly, and are easier to pull out and divide. I also have a local reed type plant that has stayed put very well, only went from probably 6" diameter to 12". I know that's double, but it's ok. Thalia tends to just grow little bit larger each year. I was told the Water Parsley (I have varigated green/white/pink type) is very fast growing. It did multiply for me last year, but not nearly as fast, and didn't take over areas.
I have a type of floating plant, not duck weed, looks like a teeny tiny oak leaf, and even turns red in the fall/winter, that I have in areas of the bog that have standing water. It's easy to get rid of, just scoop it out and throw it in for the koi, who love to eat it! If you want your open water areas to have some color, it works really well for that. Some say to keep it out of your pond if your fish don't eat it, though, as it will take over the surface.
Day lilies also do well in the bog, certain depths for certain plants. I've not tried them, but I know others have with great success. This year I'll be adding some to my bog. They multiply, but pretty much just expand, don't move far and wide.
Good luck with your plant planning!

 

[fishin4cars]

Invasive for me, MINT, pickerel rush, horses tail, water celery, money wort.