Good idea for multiple reasons: equisetum (horsetail, snake grass, puzzlegrass) (grow zone grows so quickly and make even the newest newbie of a gardener feel accomplished and happy. equisetum can get out invasive and a container will control it.
Burro’s tail cactus is not technically a cactus but a succulent. Although all cacti are succulents, not all succulents are cactus. Grow burro’s tail as a houseplant or outdoors with tips from this article.
Belgravia House in London by Todhunter Earle. Even though this is a rooftop garden, the design show would be excellent for any long, narrow yard. Great way to break up the space by making different "zones"!