In the 1700s, interior plants were considered to be capable of suffocating a person while they slept. Still, people kept plants in their homes despite the warnings (Gowan, 1987), demonstrating an inherent desire for plants. Today, an urbanized lifestyle has led to people spending 80% or more of their time in indoor settings (Fjeld et al., 1998). Many individuals and businesses continue to enhance their homes or offices with interior plants (Dravigne et al., 2008). Research has suggested that interior plants may offer some psychological and restorative values such as reduced tension (Ulrich et al., 1991), better coping mechanisms (Lohr and Pearson-Mims, 2000), and increased ability for concentration and attention (Taylor et al., 2001). A recent study found that employees in offices with plants rated their job satisfaction more positively when compared with employees in offices with no plants present (Dravigne et al., 2008). Research has found that interior plants can reduce eye irritation and stress, motivate employees, improve concentration, and even reduce air impurities (Vitiello, 2001). Plants appeared to have a positive effect on headaches and fatigue and hoarseness; even dry facial skin was reported with less incidence when plants were introduced to offices (Fjeld et al., 1998; Laviana et al., 1983).
The benefits of interior plants have been shown to positively impact stress and productivity. Reaction time on the computer improved by 12% and a lower systolic blood pressure was measured when plants were placed in a computer laboratory along with people's reports of experiencing greater attentiveness (Lohr et al., 1996). On one survey of office employees and facilities managers, only 10% of respondents thought that their offices could be improved with plants, yet 60% of office workers liked having plants around their desk. This was interesting in that it was a higher percentage than the 50% who rated the necessity of good technology as a priority (Vitiello, 2001).
Research has focused on the types of interior environments that promote good teaching and learning (Think, 2003) and found that attention paid to the factors of “light, acoustics, ventilation and ergonomics all contribute to a positive experience for faculty and students” (p. 2). Windows that provided natural lighting were important (Think, 2003), and rooms with access to only artificial light have been associated with “building sickness” (Robertson et al., 1989), which can lead to work-related headaches and lethargy. Although the subject of student and instructor preference in classroom attributes is limited, one study found that professors and students rated positive physical characteristics in classrooms similarly (Douglas and Gifford, 2001). Results found that classrooms with seating arranged to promote interaction among students, views of outdoor areas, and comfortable seating were preferred by both students and faculty (Douglas and Gifford, 2001). Using a survey of students (Dinsmore, 2003), a middle school teacher studied the perceived effects of plants, lighting, and music on students' behaviors while in the classroom. When asked if these three variables affected their learning, 43% of students responded positively to the presence of plants saying it created a more comfortable atmosphere (Dinsmore, 2003). These numbers supported the teacher's personal observations.
Research in schools has found that plants benefit the classroom aesthetically and provide oxygen while absorbing toxins (Hart, 1999). In children with attention deficit disorder (ADD), more severe ADD symptoms were seen in children when the interior classroom environment was windowless and void of natural elements (Taylor et al., 2001). A study of university students found that recovery from stress was shown to be greater for those who had plants present during testing (Russell and Uzzell, 1999).
This research supports that “A premium should be placed on ensuring that all teaching environments provide the best possible conditions to stimulate learning. The teaching environment affects how students rate their course experience, and often affects the comfort level of not only the students, but also the instructor within the classroom” (Think, 2003). Studies have shown that interior natural elements are important environmental factors for universities that can cause students to feel more comfortable, stimulating social interaction and more time spent on campus (Wiers-Jenssen et al., 2002).
The purpose of this study was to determine if interior plants in university classrooms had an impact on student course performance and on student perceptions of the course and the instructor.
Douglas, D. & Gifford, R. 2001 Evaluation of the physical classroom by students and professors: A lens model approach Educ. Res. 43 295 309
Dravigne, A., Waliczek, T.M., Lineberger, R.D. & Zajicek, J.M. 2008 The effect of live plants and window views of green spaces on employee perceptions of job satisfaction HortScience 43 183 187
Fjeld, T., Veierstedb, B., Sandvike, L., Riisec, G. & Levyd, F. 1998 The effect of indoor foliage plants on health and discomfort symptoms among office workers Indoor Built Environ. 7 204 209
Gowan, R. 1987 Plant effluvia. Changing notions of the effects of plant exhalations on human health in the eighteenth and nineteenth centuries J. Gard. Hist. 7 176 185
Isen, A. 1990 The influence of positive and negative affect on cognitive organization: Some implications for development 75 94 Stein N.L., Leventhal B. & Trabasso T. Psychological and biological approaches to emotion Lawrence Erlbaum Associates Hillsdale, NJ
Laviana, J., Mattson, R. & Rohles, F. 1983 Plants as enhancers of the indoor environment 738 741 Pope A. & Haugh L. Proc. of the 27th Annual Meeting of Human Factor Society Norfolk, VA
Likert, R. 1967 The method of constructing an attitude scale 90 95 Fischbein M. Readings in attitude theory and measurement John Wiley and Sons New York, NY
Liu, M., Kim, E. & Mattson, R. 2003 Physiological and emotional influences of cut flower arrangements and lavender fragrances on university students J. Therapeutic Hort. 14 18 27
Lohr, V., Pearson-Mims, C.H. & Goodwin, G.K. 1996 Interior plants may improve worker productivity and reduce stress in a windowless environment J. Environ. Hort. 14 97 100
Robertson, A., McInnes, M., Glass, D., Dalton, G. & Burge, P. 1989 Building sickness: Are symptoms related to the office lighting? Ann. Occup. Hyg. 33 47 59
Russell, H. & Uzzell, D. 1999 Green plants for the feel good factor. Interiorscape Magazine 8 Mar. 2005 <http://www.interiorscape.com/rentokil/>.
Sheets, V. & Manzer, C. 1991 Affect, cognition, and urban vegetation: Some effects of adding trees along city streets Environ. Behav. 23 285 304
Taylor, A.F., Kuo, F.E. & Sullivan, W.C. 2001 Coping with ADD: The surprising connection to green play settings Environ. Behav. 33 54 77
Think, M.K. 2003 University of San Francisco classroom and office standards and prototypes San Francisco, CA June 2008 <http://www.usfca.edu/planning_budget/space_planning_committee/pdf/standards.pdf>.
Ulrich, R., Simons, R., Losito, B., Fiorito, E., Miles, M. & Zelson, M. 1991 Stress recovery during exposure to natural and urban environments J. Environ. Psychol. 11 201 230
Vitiello, A. 2001 Specifying interior planting can be subjective. Plants for People Düsseldorf, Germany 19 June 2008 <http://www.plants-for-people.org>.
Wiers-Jenssen, J., Stensaker, B. & Grogaard, J. 2002 Student satisfaction: Towards an empirical deconstruction of the concept Qual. High. Educ. 8 183 195