I love the prairie and wetland habitats around the Midwest, and I do my best to plant native species as much as possible when I garden. That's my disclaimer...I'm not looking for arguments for or against native & non-native species. Just wanted to post some information for folks, since I had a hard time finding this information. :)

I'm pretty well versed in terrestrial and marginal plant species, but with my new pond, I really had to do some research to find out what kind of native species were good as floating and submerged plants. There's all sorts of lists out there for invasive plants that you might not want in your pond...but not really any comprehensive lists for "good" native pond plants. Lots of lists of marginals species, but not so much for true aquatic plants. :)

I did finally find out that hornwort or coontail (Ceratophyllum demersum) is a North American native that's pretty widely available for purchase. I also lucked into a nice start of Ranunculus flabellaris (floating yellow buttercup) from a friend with a natural pond. I didn't have any luck finding a retail source for this species.

I also got a nice email of suggestions from an aquatics guy at the Indiana DNR. It has some good advice in general...more for "natural" ponds...so I thought I'd just paste it below.

"For floating plants the best options would be spatterdock (Nuphar advena)(actually kind of emergent since the leaves don't float on the water's surface), white water lily (Nymphaea odorata), and watershield (Brasenia schreberi). Spatterdock and water lily can sometimes densely ring a pond although spatterdock has the greater tendency. Watershield is a cute little plant, but you generally only see it in the SE part of the state, I also don't think it is much used in trade. Most of the water lilies for sale are non-native species. Most of the spatterdock for sale is probably Nuphar lutea, a Eurasian species.

Most people do not look to plant submersed species since they are usually already present in most lakes and they usually show up pretty quickly after a pond is built. People typically are more interested in killing the submersed species than they are planting them. It is the water garden types of folks that get told that for their water gardens they need to put in an "oxygenator" plant. They then think that ponds need these same things. Probably the most common native submersed species in trade are coontail or hornwort (Ceratophyllum demersum) and native elodea (Elodea canadensis). Coontail can definitely become a major nuisance and sometimes elodea can as well. My main tip for those thinking they need to add submersed species is to wait. If conditions are suitable for submersed plant growth the plants will show up soon. If conditions are not good (turbid water, little shallow water, poor substrate), no matter how much planting, one will probably not get much growth. Unfortunately, invasive species tend to do well in the conditions that do not favor our natives."