Get the students to outline the story they've chosen. Once the scenes are broken down, they can attack the pieces one at a time. In a sophisticated production one might expect music bridges as transitions between scenes, but for this classroom exercise see what the kids can accomplish with plants alone. Students will have problems. One frequent obstacle we've encountered is the solitary character.
Planting requires dialogue revealing events as they happen.
Fortunately, Shakespeare's soliloquy strategy is an accepted convention of radio dramatics. I sure wish I'd listened to my mother when she warned me not to wander off. Now I'm here in the middle of nowhere. Every tree looks the same. Wait a minute.