I like creeping jenny and ajuna. I just made one from foam with ajuna in it. It takes a couple of weeks for the plants to revive from the shock of being dug up and put bare-root in just water, but I have had good success with them before. One thing I like is that in the fall I just place the foam on the ground and the plants survive the winter. After the snow and ice melt I pop it back in the pond and the plants come back to life.

I have used sweet potato vine, water celery or water mint

Verigated water celery. It's hardy and can be left in the pond all year, and if you have koi, they will keep the ends pruned for you, ;-)

I'm thinking the impatients if they're in your pond are getting sun and they're big time shade lovers, so that could be your issue. Mexican Petunia's love the water and grow like crazy! Canna lillies or elephant ears too

I tried a version of your floating island this year. Mine is just one of those garden kneeling pads from the dollar store--its foam. I cut holes in it and put in a hosta, a corkscrew rush, creeping jenny, green sweet potato vine and purple sweet potaoe. All are doing well except the purple sweet potatoe vine. The green one is growing like crazy--the purple one looks dead.

I took a hard foam ring that I bought at the craft store. I cut holes in it. I then painted the bottem and inner bottem holes with craft paint. I then planted the impatiens in it after i rinsed all the dirt off. I made sure I got some of the root to the bottem so it would soak up the water. I then took clear fishing line and attached each plant in its place because the falls was spinning it around and the plants were leaning over. The ring is filling in nicely and its in full Minnesota sun. This is my first year with a pond so I am experimenting.

What other annuals can you plant without dirt in full sun in the stream? I am trying impatiens and nasturtiums on the side. Any help? Thanks

We have specialized planting mix to go with mini islands that we manufacture. You are welcome to visit our web page, or call with any questions. We'd be happy to help.