You can cut the stems back to the soil level and hope for the best. How did this happen? Whatever conditions caused the problem should be corrected.

Is there drainage holes in the bottom of your container?

FataMorgana

@fatamorgana: are you recommending a container without drainage holes? i rooted some rau ram cuttings that i got from the vietnamese grocer and have more rooted than i know what to do with. so i planted some in a container without drainage holes and some in traditional pots as a sort of an experiment. i've read that they are sold as aquarium plants! so it seems that it would be hard to overwater them.

Fatamorgana is just checking that the can DOES have holes. Even bog plants need drainage. Growing them in containers is very different from growing them in the ground. Also it looks as if that container is metal. If that's the case, the roots may well be cooking if the canister is in the sun. Your plant looks scorched and parched.