I have Lobelia cardinalis along a stream bank that floods on a semi-regular basis, but the water does not stay there long. These plants hang on to the bank fairly well, and rarely do they "float" away. Same with NY Ironweed Vernonia fasciculata. The lobelia around here grows along water because, since it doesn't like its evergreen rosette to be covered by heavy, winter leaves, the occasional flooding keeps the leaves off in winter, when we have more of our heavy rains. Oh, ruellia around here occurs in damp places, but I am not sure where they really "like" to be. I also am not sure of the hardiness zones for these plants that I just mentioned...I am in zone 7, and you are definitely in a much colder zone. Just noticed that.

Wetland plants are appropriate for that very scenario. They like wet feet, but can tolerate dry summer peroids and even years of drought. That is the defination of a wetland, fluctuating water levels. Joepyeweed is perfect that scenario. So is asclepias incanarta, swamp milkweed. Lobelia cardinalis is a great suggestion by ncrescue. Indian Grass, big bluestem can also tolerate those conditions. Any plant listed appropriate for a rain garden would probably due well there also. Fox sedge, bottle brush grass, columbine, zig zag golden rod, cupplant, rosinweed, mondarda fistulosa, are a few others that come to mind also.

Thank you! This is valuable information from both of you, and I greatly appreciate it. I was concerned that some of these plants would not survive the flooding, you have eased my fears. Plus, I had not added Lobelia cardinalis, how could I forget? Thank you. Now to order my baby plants.

Ann

Oh, I almost forgot. One more question. Do you think some shrubs would also survive this periodic flooding? I know that hawthorn survives as there is a native one right at the corner. But I was thinking of adding elderberry, wild plum, maybe a couple of others. I especially prefer ones with berries for the birds.

Thanks again.

The impact of the flooding will depend on the length of time that the area is flooded and the frequency of flooding. Long, frequent flooding would mean that the soil would become anoxic due to saturation and wetland plants would be appropriate. Plants are not usually affected because their tops go under water, but because the soil is saturated for too long, which reduces oxygen movement into the soil and causes the soil to become anoxic. it generally takes at least a few days of flooding to strongly impact plants.

Looking at your picture I don't think you should be concerned about the occasional flood. Does the lawn grass or corn die because of flooding? The small spruce has been there a couple of years, at least, and is fine. It is not a wetland plant. I am trying to say that I don't think wetland plants are necessary. I think a prairie would be fine. Most native plants, including most prairie plants, are reasonably tolerant of occasional flooding. You might want to choose the more moisture-loving prairie plants, instead of the ones from really dry soils.

There are many shrubs that do fine in wetlands, and even more that do fine in periodically flooded areas. Elderberry, many viburnums, wild plum all should do fine. In fact I think almost any shrub will do fine here because it doesn't seem to be all that wet, based on the picture.

Button bush would be a good shrub there.

Oh and I almost forgot about liatris for a flower recommendation.

NCDMV has started constructing rain gardens at many of the rest stops...to control the runoff and possible flooding. They have planted clethras in many of them, and yes to elderberry, button bush. There is also a native spirea that grows along river banks around here...maybe threatened or endangered...but I have one that is doing fine in a ditch that is often flooded. Sorry that I cannot remember the specific name.

I have Joe Pye Weed growing in both wet and dry areas. I understand that prairie cord grass can take the occassional flood also. My elderberry shrubs withstand the occasional flood just fine and seem to prefer areas where that happens. I'm in the northeast so take that into account when considering any info I share.

Blueberries are suggested for rain gardens in this area. As a suggestion since your garden will be an on going project. Get a book of wild shrubs with good pictures and take walks along the stream beds in your area matching the vegetation to the book. When you see a plant you like try to find at a nursery. Do not dig the plant up unless it is a rescue.

These are wonderful suggestions, and I appreciate it much!

maifleur, I would dearly love to grow bueberries, but I believe they like acidic soil and ours is alkaline. Bummer.

button bush - I don't know that one, I'll have to go find it.

Liatris! I forgot that one too, glad to know it can survive flooding as it is one of my favorite prairie plants.

ladyslpper - to try to answer your questions about duration of flooding - the picture I posted is from last spring and is the worst flood since we've lived here (and number 5, I think, on the recorded floods for our area). In that case, the water would have covered that area for at least two weeks. But, that was before anything started growing and there was no apparent damage. I am more worried about the occasional summer flood, after plants have emerged. The one we had three years ago covered that area for a week or less, but yes, it did kill the grass. And, I can't remember what crop was in the field that year, but it did kill the crop too (soybeans, I think). My impression from that (which may be completely wrong) was that if the plants are growing and get covered by water it will kill them, if the plants have not yet emerged they will survive.

I'm probably simplifying far too much.

Thank you all for the great suggestions, there's several more I need to look up now (button bush, clethra, spirea for our area...)

Ann

The wetland plants just might go dormant during an extended flood, but they will resurface/resprout when conditions are right.

All of hte plants I listed I have seen growing in areas that are inundated for weeks or longer. Remember the Mississippi Flood of 1993....plants along the river bottom or on the islands were under water for almost an entire summer that year, were just fine and growing the following year. Some may have moved a bit though...

Rose mallow or marsh mallow is another one that comes to mind.