maybe cannas or elephant ears. We have both growing in our stream

Rose Mallows ( Hibiscus)

How about bog plants? Arrowhead plants are neat. They look like caladiums. I have some that pop up whenever it's wet and go dormant when it dries up. You might check out water garden pages for "marginal plants," the ones that would ordinarily border a pond.

Ooo, cattails!

If you're at all interested in a tree for that area, bald cypress love standing water and develop interesting "knees" around their base with enough of it.

Mmm, makes me long for standing water ...

Bald cypress sends knees "waaaaaaay out" farther than their base. I have 5 of them, and there are areas I cannot mow because of the knees. This year, I plan to make shade beds between them.

I have Variegated Sweet Flag (Acorus) in my water garden and in a "damp for days when rains" area. It comes in a gold/green strip and white/green stripe foliage - looks like a short bunch grass or caryx(?) about 12" tall and the golden looks really pretty with the sun behind it. It spreads a little each year, but not invasively so far. I found it at HD.

Umbrella grass may not make it thru your winters but I think it might come back in the spring. Depending on how much water it gets, it can get as high as 3 or 4 feet. Has a nice tropical look. Here in zone 9, it is almost invasive if it weren't so easy to pull up. It perseveres thru our clay soil and thru droughts but seems to like water the best.
picture here

Here is a link that might be useful: Umbrella Grass

I have the Japanese umbrella plant in my small pond, but the largest ones I have (and would really like to get them dug out and moved), get about 8 to 10 feet tall, and they get no special care or water. Guess you could say they are a really hardy plant.

I have the same problem, a low area that always floods and holds water because my neighbor raised the grade of his yard.

Anyway, I planted a swamp rose which had done very well and has stood in water for up to two weeks without damage. I also planted Louisiana Irises and canna lilies.

And I planted a bald cypress which I love, but as they get older they do get those knees. I would suggest the Montezuma Cypress (zones 7-10). I have read that it is believed not to do all that well north of San Antonio, but I have read about one growing in Plano and is doing very good.

Bushy bluestem is another plant that likes wet feet and grows primarily in low moist sites. Ferns, especially wood ferns do well.

I don't grow the umbrella plant, but everyone that I know wishes that they hadn't planted it.

lt is right, Montezuma cypress (Taxodium mucronatum) will survive here north of Ft. Worth (Justin). I've got one going on its 3rd year. The first winter, it took a 4°F morning in December with no ill effect. I don't think they like the boggy conditions like their cousin bald cypress, though. In their more native range in Mexico, they are supposed to line streams and rivers as well as upland sites. They do not put up knees like the BC.
May be tough finding one around here.
J.D.

I did a search on Texas Smartscape and indicated high water demand plants and came up with the following list of plants:

Bald Cypress
Tassel Fern
Louisiana Iris
Japanese Aucuba
Little Gem Magnolia

I don't know if the magnolia would take standing water, but the others might be okay.

I would question the Japanese Aucuba. I had one in moist area for several years. Then we had a water leak in the sprinkler system by it, and it croaked in a heartbeat.

Let me add a wrinkle that I should have included in the original post. I'd like something that is evergreen and will live through our winters, and I want plants, not trees.

I'm demanding, eh? =)

Thanks for the help so far!

Check out this site to see if it helps http://www.victoria-adventure.org/aquatic_plants/index_of_images.html.

Or this website from TAMU.

My Louisiana iris have stayed green through the winter when I have mulched them well & covered them when temps dropped below about 27.