Like humans and other animals, plants need sufficient nutrients to function and to grow. If the plant is deprived of these nutrients, it is unable to go through the chemical processes related to its survival and growth. Cigarettes contain more than 4,000 different chemicals, including arsenic (used as rat poison), butane (lighter fluid) and formaldehyde (fluid used in embalming). Some of these chemicals actually may benefit the plant. Carbon monoxide, for example, is able to be converted by the plant into carbon dioxide, which the plant can use readily for photosynthesis.
In general, however, most chemicals released during smoking contaminate the soil and air surrounding the plant to such a degree over time that the plant eventually cannot absorb sufficient amounts of the nutrients needed to sustain itself and to grow.