I know that recently, Arkansas has banned the sale and possession of water hyacinth. I also know that any that I purchased prior to the ban is okay for me to have, but that I won't be able to buy anymore, because it's now illegal for nurseries to sell it. I have a small - 350 gallon - pre-formed pond in my back yard in which I have always placed water hyacinth. The plant will not survive the winter in the pond, because it's not deep enough, only about 30" at the greatest depth. If I take some of the plant and over winter it in a tub in my house to put back in the pond next spring, am I in trouble?
For clarification, I checked with my friends at the Arkansas State Plant Board who regulates such matters. Plants contained on the prohibited plant list present such a danger to the natural ecosystems in the state that they are prohibited. This means they cannot be sold or used in plantings in Arkansas. Water hyacinth multiply like rabbits, and can clog up waterways. If you had the plant in your garden this season, you were allowed to keep growing them, since they were just added to the list. But from now on, you can’t have them, so the answer to your question is no, you can’t save them. Add them to the compost pile and find a new water plant. There are many to choose from. Other plants on the prohibited list include: purple loosestrife, giant salvinia (Salvinia molesta), water hyacinth and Japanese blood grass. Japanese Blood Grass was just added along with the water hyacinth. This red-tipped ornamental cultivar, Imperata cylindrica ‘Rubra,’ is extensively promoted as Red Baron, or Japanese Blood Grass. It has been sold and grown as an ornamental for some time, and can turn a beautiful red color in the fall. However, they have found that it can revert to Cogon grass: Imperata cylindrica which has been ranked as one of the ten worst weeds of the world.