Facts & Figures

Raymond Biesinger (Illustration)

Nervous NASA gets green fingers


When America’s space agency, NASA, realized in the 1980s that modern, sealed buildings that were highly energy-efficient triggered illness-like symptoms in residents or employees, it started to worry about its astronauts. As it turned out, various substances that originated from building materials, paints, coatings or cleaning agents would accumulate in sealed buildings. To prevent formaldehyde, trichlorethylene, benzene, xylene and ammonia from fouling the air in spaceships and on space stations, thereby endangering missions, the researchers at NASA hit on a simple solution: Potted plants were effective filters that could remove these substances from the air. The final report on the topic singled out the peace lily and garden chrysanthemum for special praise. Both plants were shown to filter all five of these pollutants from the air.

Filter factfinders


Numerous studies have focused on the filtration of pollutants using plants in an urban setting. With regard to the positive effects, a study group led by Thomas A. M. Pugh from Lancaster University in England, the U.S. Forest Service under the aegis of David Nowak as well as the University of the West of England in Bristol and the Fraunhofer Institute for Environmental, Safety and Energy Technology are on the same page.

Growing on walls


As early as 1988, vertical gardening pioneer Patrick Blanc patented his process for growing plants on reinforced concrete walls. The principle is based on metal frames with PVC plates over which a felt-like synthetic fleece is stretched, allowing the plant roots to gain a hold.



Definition: Plants are living organisms that belong to the domain eukaryota. In other words, they are organisms with a cell nucleus and a cell membrane.

Family tree: Domain: eukaryotes (eucarya). Kingdom: plants (plantae). Divisions: vascular plants (tracheophyta), liverworts (marchantiophyta), true mosses (bryophyta), hornworts (anthocerotophyta).