Office Plants from Green Thumbs to Good Eye Health
1. The Evidence – Green Thumbprints
1.1 The University of Cardiff Study
The inaugural study of the effect of plants on the workplace, conducted by the University of Cardiff, was announced on the university website under the title, “Flower Power”. Flippant but apt, the title refers to the stunning findings of the study, which indicate that the addition of some leafy green to a plant-deprived office can engender a rise in employee productivity of up to 15%. This claim was proven Marlon Nieuwenhuis of the School of Psychology at the University of Cardiff. Coauthors include Dr Craig Knight of the University of Exeter as well as Professor Alex Haslam from the University of Queensland School of Psychology in Australia. In their study – the first of its kind – they researched the influence of office plants on work, employee productivity, a sense of wellbeing and room climate. The research team carried out is study over several months in three open-plan offices in the UK and the Netherlands, observing the happiness of company employees, measuring air quality and conducting studies on employee concentration. The results could not have been clearer and negate the assumption that bleak working conditions improve concentration. Indeed, well-tended greenery is definitely not a distraction, serving to measurably increase focus at work. The improvement in air quality was equally significant. And last but not least, employees reported feeling noticeably healthier and more content.
1.2 Common Sense
It is fantastic that a team of well-known researchers has brought forward this evidence – after brief consideration, the results are logical, too. Originally, man was known as a part of nature rather than a part of the office. And those who have ever gone for a springtime stroll through lush green fields or a newly budding forest know the feeling of unexplainable joy that comes with so much green. Scaling this teeming green mass down to a few square metres of office space, you will probably not experience such raw, sublime emotion, especially since there is another small priority to take care of at the office: work. Nevertheless, man needs oxygen in order to function, and plants, incidentally, are famous for producing oxygen. As a result, improving air quality in the office is a simple matter of having plants at work. The difference between a healthy, pleasant environment and overt distraction should hence be clear. Plants contribute to the former.
1.3 Confirmation from an Expert
Jan Gisewski from Ambius Germany makes reference to similar studies. The qualified horticultural engineer is the company’s branch manager for “Interior Plants and Landscaping”. Ambius is a division of the multinational logistics service, Rentokil Initial GmbH, specialising in the delivery and care of plants in commercial interiors. This includes offices as well as waiting rooms, shops, buildings with public access, hotels, hospitals and doctors’ practices. “Plants provide stress relief, filter toxins in the air, relax the eyes and improve overall wellbeing”, he confirms. Adding some greenery to the workplace does not only guarantee a better ambient climate, more oxygen, better sound insulation and a more pleasant work environment – it also heralds financial rewards. Gisewski cites a study wherein “employee sickness rates decreased by as much as 3.5 days per employee per year”.
Office interiors often conform to a particular design concept, so Gisewski recommends a whole-office solution. “Large open-plan office spaces place particular emphasis on an overarching design concept, which might also reflect the style or views of the company. “If every employee decided to bring a different cactus to work, each in a different pot, it would be counterproductive to company image.” Gisewski suggests targeted interior landscaping that considers the nature of the business premises, the design objective of the client, the availability of space and lighting and, of course, the budget.
2. Putting it into Practice
2.1 The First Step – Consultation
There is a logical order of things in creating an office space: whether the office has just been built or is an established company HQ, furniture normally comes before plants and interior landscaping. An on-site consultation will determine the availability of space for plants as well as light exposure and the functions the plants are to fulfil. For a general increase in humidity and air quality, experts choose plants with large leaves, which also require significant amounts of light, water and air. Gisewski indicates “the rule of thumb: the more surface area in foliage, the more water the plant can distribute to its leaves to create oxygen.” To foreground aesthetics, the vessel or pot will be just as important as the plant itself. “There are pots by designers like Colani and designer article manufacturers such as Koziol, there are plant troughs inlaid with mother of pearl – there is quite simply nothing that there isn’t.”
2.2 The Best Possible Compromise Between Man and Nature
Adding greenery to the office space is, above all, about compromises. This becomes evident when Jan Gisewski talks about his job. Not only does man demand certain things of plants, but plants – which don’t naturally grow in buildings – need conditions to allow them to flourish in turn. Interior landscapers tend not to search for the perfect solution but for the best possible compromise between man and nature. Jan Gisewski’s team is currently responsible for the care of almost 30 000 plants, and performs diverse tasks such as planting, pruning, watering and providing fertiliser. Gisewski has come to appreciate that general rules, although they yield a good benchmark, are always counterweighted by exceptions. First, there is the case of 30 typically behaving weeping figs (ficus benjamina), which get plenty of light and water and which are susceptible to air draughts. “And then there is weeping fig Exemplar No. 31, which stands neglected in a dark corner, gets hardly any water and endures gale force winds – because no one told it that it should have withered and died a long time ago.” Gisewski’s comic example shows that plants are living things and can be just as different as human beings.
2.3 The Fig Myth
The weeping fig is a popular indoor plant that is relatively easy to care for and is thus widespread in office spaces. However, it has long been accused of causing allergic reactions. Fact or fiction? “I cannot attest to its [the weeping fig’s] harmlessness”, Gisewski admits. The weeping fig is closely related to the rubber tree, and its whitish sap is, in fact, rich in rubber. “If somebody with a rubber allergy came into contact with it, the sap could definitely trigger an allergic reaction.” At the same time, there is the assumption that the fig binds allergens into the dust it attracts. “This has not yet been disproven”, states Gisewski. He does note that such rumours should be regarded with caution, especially in the age of internet technology. Nevertheless, the fact is that reports of allergic reactions are almost entirely limited to this fig species. There are as good as no similar reports concerning the many other fig and rubber tree species.
3. Tips & Tricks
3.1 Soil – A World of its Own
Let us assume that no interior landscaping company was hired and that office workers had free rein in marrying greenery with the office. In this case, there would be one or two things to keep in mind in order to maintain a streamlined design throughout the office and to keep plants in good health. For example, sometimes office plants are potted without soil, a planting method that calls for a high degree of plant care and can be irreconcilable with holidays or even a long weekend. Since the beginning of the 1960s, a system has been developed to make plant care less work, and it has borne some remarkable fruits. In many cases, plants only have to be watered once a month. Hydroponic systems often use an inorganic, baked clay plant granulate. The plants draw nutrients from water and nutrient solution, which are accumulated in specialised watertight troughs. The plants absorb and nutrients steadily over longer periods, remitting the need for watering. Watering is done through the “ebb and flow” principle, meaning that the trough is refilled only once the water has been completely metabolised by the plants. Note that for this growing method, plants should develop “water roots” in the first few years of growth.
3.2 Plant Selection in the Jungle
In the choice of office plants, Jan Gisewski recommends looking south. “North European plant species are generally not suited to interiors because they are accustomed to the different seasons. The enthusiasm for your plant will probably wane if it begins to show symptoms of autumn and winter”, Gisewski laughs. If you don’t like raking up dead leaves in autumn and don’t want sordid-looking pot plants in winter, look to more southern latitudes, to the rainforest. “In an office environment, the temperature is stable at about 17-20°C throughout the year, which is appropriate to the needs of subtropical plants.” These also require relatively little light. Gisewski recommends a variety of fig species, dracaena species, schefflera species and kentia or areca palms. “These plants make up about 70% of mass office landscaping. In the last few years, there has also been a resurgence in a plant that most people know from their grandmother’s windowsill: sansevieria.
4. Sources:
Study by the School of Psychology, Cardiff; specifically: Marlon Nieuwenhuis, CraigKnight, Tom Postmes and Alexander S. Haslam conducted a study entitled, "The relative benefits of green versus lean office space - Three field experiments", which researched the influence of plants on work and work output. This text first appeared in the "Journal Of Experimental Psychology: Applied, Vol 20(3), September 2014, pages 199-214. It is cited in a large number of articles. Homepage of the University Of Cardiff: Interview with Jan Gisewski, Dip. Engineering (Horticultural), branch manager at Ambius Germany. Ambius is a division of Rentokil Initial GmbH.
