Particularities of having plants at home during the confinement due to the COVID-19 pandemic.

1 Particularities of having plants at home during the confinement due to the COVID-19 pandemic Luis Pérez-Urrestarazu a* , Maria P. Kaltsidi a , Panayiotis A. Nektarios b , Georgios Markakis c , Vivian Loges d , Katia Perini e , Rafael Fernández-Cañero f a Urban greening and Biosystems Engineering research group. Department of Aerospace Engineering and Fluids Mechanics. ETSIA Ctra. Utrera km.1, 41013. Seville. Spain. E-mail address: [email protected] and markal[email protected] b Hellenic Mediterranean University, Department of Agriculture, Laboratory of Floriculture and Landscape Architecture, Estavromenos, Heraklion, Crete, 71410, Greece. E-mail address: [email protected] c Hellenic Mediterranean University, Department of Social Work, Estavromenos, Heraklion, Crete, 71410, Greece. E-mail address: [email protected] d Departamento de Agronomia, Universidade Federal Rural de Pernambuco. UFRPE Rua Dom Manoel de Medeiros, s/n, Dois Irmãos, 52171-900, Recife-PE. Brasil. E-mail address: [email protected]m e Architecture and Design Department, University of Genoa. Stradone S. Agostino 37, 16128- Genoa (Italy). E-mail address: [email protected] f Urban greening and Biosystems Engineering research group. Department of Agro-Forestry Sciences. Universidad de Sevilla. ETSIA Ctra. Utrera km.1, 41013. Seville. Spain. E-mail address: [email protected] * Corresponding author: Telephone number: +34 954486480; E-mail address: [email protected] 2 Abstract The present study evaluated the role of having plants at home during the confinement period as a result of the COVID-19 pandemic that deprived people of freely visiting open green spaces. Preferences concerning the quantity of the desired vegetation as well as the ways in which the COVID-19 crisis affected the change of perceptions with regard to having plants at home were also evaluated. A questionnaire, which was filled by 4205 participants, provided an undistracted evaluation of the impact of indoor and outdoor plants on their emotional welfare considering behavioural, social, and demographic variables. The emotional state of the respondents was neutral and a significant proportion expressed positive emotions. Having indoor plants was correlated with more positive emotions, and confined inhabitants allocated more time for plant maintenance. By contrast, negative emotions prevailed in respondents who related to a positive COVID-19 case, which was more frequent in females and young participants living in small houses that received low levels of natural light and had few or no plants. A few indoor plants placed in strategic positions were also preferred compared with a high number of plants. By contrast, an increased amount of vegetation accompanied by living walls was preferred for outdoor settings. Living walls were considered as advantageous for increasing indoor vegetation, but they were also associated with technical and economical hurdles. Keywords: emotional well-being, indoor vegetation, contemporary planting systems, living walls, psychological impact, human-plant interactions 1. Introduction 3 Urban green space (UGS) can play a key role in well-being (Mavoa et al., 2019; Navarrete- Hernandez & Laffan, 2019) and people tend to visit them for leisure, to practice sports, to relax or socialise as frequently as possible. But what happens if this is impossible? The health crisis caused by the SARS-CoV-2 virus led to an imposed confinement in many countries around the world (Tobías, 2020). In this unprecedented situation, people were forced to remain at home for several weeks without the possibility of moving around freely. Although house confinement has been proven to be a key factor in controlling the spread of the disease, it has also resulted in the occurrence of undesired effects such as a reduction of economic activity and the cause of psychological repercussions related to the compulsory home reclusion (Shigemura et al., 2020). More specifically, preliminary studies performed with regard to human psychological reactions to the COVID-19 pandemic indicate that anxiety and depression (16–28%) as well as self-reported stress (8%) were amongst the most common symptoms (Rajkumar, 2020). Moreover, Bezerra et al. (2020) observed that having a household with an open area, such as a terrace, or with a green area proved helpful during the period of isolation. Many studies have reported a number of psychological benefits to humans who are exposed to nature. For instance, White et al. (2013) investigated the relation between urban green space and well-being and mental distress and demonstrated that individuals living near green spaces exhibit both lower mental distress and higher well-being. Visual and physical exposure to plants has been related to increased positive behaviours and pleasant feelings in conjunction with reduced negative feelings such as anger, fear, and stress (Adachi et al., 2000; Kamitsis & Francis, 2013). These psychological benefits might be related to the so-called biophilia concept (i.e., a preference for interacting in a natural environment as a consequence of our evolutionary course) and based on theories of restorative effects (i.e., regaining psychological, social, and physical capacity) (Grinde & Patil, 2009). In this regard, a study by Hernández and Hidalgo (2005) showed that urban environments with natural elements yielded higher restorativeness (reducing mental fatigue and stress). This nature-perceived 4 restorativeness (through cognitive reappraisal) can help to promote appreciation of nature and act as a motivator for pro-environmental behaviour, creating more environmentally aware citizens (Berto & Barbiero, 2017; Carrus et al., 2015; Panno et al., 2020). Furthermore, evidence shows that there is an implicit link between “nature” and “outdoors” that results in lower attention attributed to indoor vegetation settings (Bringslimark et al., 2009). However, in contemporary societies, the increasing amount of time spent indoors often results in separation from the natural environment (Aries et al., 2010). Living in environments with minimal or absent use of plants could lead to negative behaviours, such as irritation or hostility (Lederbogen et al., 2011). These behaviours might be particularly applicable to the COVID-19 pandemic confinement, which was aggravated by additional negative emotions of fear, disappointment, uncertainty, and stress (Brooks et al., 2020). Therefore, in such difficult circumstances, the inclusion of natural and living elements, such as plants, could reintroduce nature into human living spaces and reconnect humans with natural environments. Connections of this type have been proven to induce positively-valued changes in cognition and emotion and to express a beneficial impact on stress level, health, and well-being (Grinde & Patil, 2009). It is interesting to point out that Han & Ruan (2019) reviewed 50 studies and concluded that the most noticeable effect of indoor plants on people’s behaviour was their capacity to increase positive emotions and to reduce negative feelings. For instance, a decrease in the perception of pain, fear, unhappiness, and aggressiveness has been found to be associated with the presence of indoor plants (Burchett et al., 2008). In addition, stress seems to be reduced in indoor environments enriched with vegetation compared with indoor spaces without plants (Park et al., 2008; Thomsen et al., 2011). Vegetation can be introduced in living spaces in various ways and forms, which are usually determined by the specific characteristics of the property and the building, including space and natural light availability. When outdoor spaces are available, vegetation can be introduced as 5 lawns, bushes, or even trees in backyards, front gardens, terraces, patios, or accessible green roofs. However, in contemporary cities the prevalent architecture with apartment houses and skyscrapers has resulted in reduced outdoor spaces, which are often mainly reserved for suburban areas. Therefore, many inhabitants seek alternative ways to introduce plants within their living spaces. In most cases, this is achieved either by traditional techniques, such as pots and flower beds, or contemporary approaches, such as vertical greening systems. Innovative indoor living walls are systems that use advanced techniques to enable the covering of walls, or any other vertical or inclined surfaces, with plants that are rooted in and growing on specialised media along the vertical surfaces (Pérez-Urrestarazu et al., 2015). These contemporary indoor greening techniques are aesthetically pleasing while being used as a means of introducing an increased number of plants within a limited area inside the house. The aim of the current study was twofold: a) to evaluate the impact of having plants at home during the COVID-19 pandemic confinement on people’s emotional welfare considering behavioural, social, and demographic variables and b) to determine participants’ preferences towards different ways of introducing indoor vegetation by comparing traditional and modern greening techniques. The research was conducted on a worldwide scale, but focused on four countries based on interviewee responses: Brazil, Greece, Spain, and Italy. The main research questions can be summarised as follows: 1. Did having plants at home contribute to the emotional welfare of the people during the COVID-19 confinement period? 2. Was there a difference before and after the COVID-19 confinement period with regard to people’s perception of having plants at home and interacting with them? 3. What are the preferences towards different types and levels of vegetation? 4. Are living wall systems known and appreciated as an option to increase indoor vegetation? 6 2. Methodology 2.1. Questionnaire design and survey distribution The questionnaire was developed to be anonymously responded online using Google Forms. It was translated into English, Italian, French, Greek, Portuguese, and Spanish. At the beginning of the questionnaire, the rationale and the goals of the study were introduced to the potential respondents while general information, including the participating universities, the confidentiality of the research, and the intended management of the collected data, was also provided. The questionnaire comprised 38 questions distributed in six different sections (Table 1 in Annex A). Section 1 of the questionnaire concerned basic personal and demographic information, confinement duration and exposure to any COVID-19 related incident within the family and social circle. In Section 2, the participants were asked to provide information regarding their houses, such as surface, room number, availability of outdoor spaces, and number of inhabitants. In Section 3, the aim was to evaluate people’s attitudes towards nature based on their interest in gardening, their visiting frequency of outdoor green areas as well as the number of plants hosted at home. The fourth section comprised a series of questions aimed at determining the respondents’ emotional state during the COVID-19 confinement period and its correlation with plant number along with plant maintenance and position (indoor or outdoor) in the household. In this section, two questions (#28 and #29) were considered as the cornerstones in detecting a potential correlation between inhabitants’ emotional welfare and plants during the pandemic confinement period. In Question #28, participants were provided with different positive (optimistic, calm, cheerful) and negative (depressed, fearful, stressed, sad) emotional states and were asked to state the frequency of experiencing these feelings ranging from ‘never’ to ‘many times’. These results were used to calculated an ‘Overall emotional well-being’ indicator. In Question #29, the participants were asked to express their opinion on whether 7 having vegetation at home positively contributed to their mood during the COVID-19 confinement period. In section 5, the aim was to fine-tune the participants’ preference with regard to the type and amount of indoor and balcony vegetation. This was further reinforced by the inclusion of three sets of pictures. Each set included a photograph of the same house location having different quantity and quality levels of vegetation (Fig. 1): (A) no plants, (B) few (5-7) plants in pots, (C) many (more than 7) plants in pots, (D) many plants in conjunction with living walls. The four scenarios were simulated using Photoshop (CS6 Extended). The majority of the questions were of the closed-form type and formulated in the ‘multiple choice’ format. The questions and the different response options are presented in Table 1 (Annex A). 8 Figure 1. Scenarios simulation of two rooms and one balcony with increasing quantity of vegetal elements: (A) no plants, (B) few (5-7) plants, (C) many (more than 7) plants, (D) many plants in conjunction with living walls (the scenarios were simulated using Photoshop CS6 Extended). The distribution of the questionnaire was performed mainly through social networks (WhatsApp, Twitter, LinkedIn, Facebook), although other communication channels, such as emails and links in web pages, were also used. Though this method does not allow to control the characteristics of the potential respondents, it permits to acquire a bigger sample within the tight time limits of the confinement period. The questionnaire was open from April 25 th until May 4 th , 2020. During that period, as a preventative measure against coronavirus, people were still confined and/or in lockdown in most of the participating countries. 2.2. Participant numbers and countries of origin The total number of participants who answered the questionnaire was 4205. Responses were obtained from 46 countries from all over the world (Fig. 2). Most responses were received from Brazil (29.6%), Greece (23.8%), Spain (19.6%), and Italy (9.4%). The number of responses from those four countries was enough to be statistically significant considering the population in those countries, with a confidence level of 95% and a margin of error ≤5% (Kotrlik & Higgins, 2001). 9 Figure 2. Distribution of the collected questionnaire responses based on the different countries and their colorimetric categorisation based on the total number of responses per country. The distribution of participants based on gender and age is provided in Figure 3 as well as the distribution of responses according to the participants’ highest level of education. From the total collected data, 43.6% of the respondents were male and 56.1% female. Only 19.9% were between 18 and 26 years, while most of them were within the 26-40 (39.1%) and 41-65 (39.5%) age ranges. The responses obtained by elderly people were particularly important for this study since 4.5% of the participants were over 65 years old and comprised an age group especially susceptible to the effects of COVID-19 (Du et al., 2020; K. Liu et al., 2020; Onder et al., 2020). 16 and a minimum percentage (3.2%) believed that indoor plants did not influence their emotional welfare. Table 3. Distribution of indoor and outdoor plant number per household. Number of plants 0 1 - 3 4 - 7 8 - 10 > 10 Indoors (%) 26.5 35.6 18.6 7.2 12.1 Outdoors (%) 7.8 13.2 14.5 10.2 44.8 The most common way of introducing vegetation in the house involved using pots or flower beds in both indoor and outdoor settings (Fig. 5). Trees and shrubs were amongst the most frequent types of outdoors vegetation. Other ways of greening, such as climbing or hanging plants, lawns or vegetable gardens, were less common, while living walls were not a popular option since they were only used by less than 4% of the respondents. Figure 5. Different categories of indoor and outdoor vegetation per household. 3.4. Emotional state and attitudes towards plants during the COVID-19 confinement period The participants exhibited moderate feelings during the confinement period since, in most cases (41.9-63.5%), the most frequent response was “sometimes” in relation to the frequency 17 of their feelings and mood during the confinement period. However, certain feelings prevailed in some cases. More specifically, 54.3% responded that in many instances they were calm, with 39.7% being optimistic and 35.4% cheerful. Further support for the respondents’ positive attitude during the confinement period may be derived from the fact that 38.2% reported that they never felt depressed, 32.3% never felt fear, and 25.8% never felt sadness. The variables that were determined to significantly affect the ‘Overall emotional well-being’ indicator of the participants during the COVID-19 crisis are presented in Table 4. A higher mean value of the indicator implied more frequent negative emotions and less frequent positive emotions. More frequent negative emotions were experienced by those respondents who were directly related to a positive COVID-19 case, were of female gender, and belonged to the 18-25 age group. Furthermore, negative emotions were more frequently experienced by residents living in small-sized houses (<40 m 2 ), by those receiving low or no natural light inside their house, and by those who did not visit green spaces frequently prior to the crisis. Moreover, the frequency of negative emotions prevailed when the responders did not have many indoors plants. Surprisingly, having plants outdoors did not seem to have any significant influence on the emotional well-being of the participants during the lockdown period of the pandemic. Table 4. Variables significantly affecting the ‘Overall emotional well-being’ indicator (mean and standard deviation [SD]) of the participants during the COVID-19 crisis. Higher mean values indicate more frequent negative emotions and less frequent positive emotions. Different letters within the same variable indicate significant differences between the options using Tukey’s honest significant difference (HSD) at 5% probability level (P < 0.05) Factor Option N Mean SD Directly affected by COVID-19 (F=110.5; p<0.001) Yes 667 13.23 2.7 a No 3538 12.07 2.6 b Age group (F= 45.88; p<0.001) 18-25 710 12.95 2.8 a 26-40 1645 12.5 2.6 b 18 41-65 1662 11.83 2.5 b 66+ 188 11.23 2.6 c Receiving natural light indoors (F=28.9; p<0.001) Not at all / Little 587 12.84 2.6 a Some 1348 12.56 2.6 a Quite a lot 1487 12 2.7 b A lot 783 11.78 2.5 b Frequency of visiting green spaces prior to the crisis (F=15.36; p<0.001) Daily 1133 11.87 2.6 a Weekly 1811 12.25 2.6 b Monthly 649 12.59 2.7 c Less than once per month 611 12.62 2.8 c House size (F=12.12; p<0.001) < 40 m 2 229 12.83 2.7 a 40-70 m 2 964 12.53 2.7 ab 70-100 m 2 1247 12.31 2.6 b 100 - 130 m 2 891 12.18 2.7 bc > 130 m 2 874 11.8 2.5 c Gender (F=10.06; p=0.002) Female 2358 12.36 2.7 a Male 1823 12.1 2.6 b Number of indoor plants (F=6.75; p<0.001) 0 1115 12.47 2.7 a 1-3 1496 12.35 2.6 a 4-7 783 12.16 2.5 ab 8-10 304 11.81 2.8 b >10 507 11.92 2.7 b When the responses from the collected questionnaire data were compared with the four major contributing countries (Spain, Italy, Brazil, and Greece), several differences were detected (Table 5). The impact of a positive COVID-19 case resulted in negative emotions in all countries and for the total sample. However, the responses from the total collected questionnaires showed that Spanish and Brazilian respondents of 18-25 years experienced more frequent negative emotions, while age was not a contributing factor for Italian and Greek respondents. It is worth noting that in Brazil negative emotions prevailed in respondents of 26- 40 years who lived in houses sizes ranging from 40 to 70 m 2 . Negative emotions were more frequent in Spanish and Brazilian women and Greek men, while gender was not significant for the Italian respondents. An indifferent emotional state was observed for the following factors: levels of indoor natural light in Italy; frequency of visiting green spaces prior to the crisis in Spain, Italy, and Greece; 19 house size in Greece; number of indoor plants in Spain, Italy, and Greece. The complete results of the statistical analysis are presented in Annex B along with the differences between countries. More than half of the respondents (55.8%) stated that they would have preferred to have more plants in their house during the confinement. Conversely, 60.3% of the householders declared their unwillingness to increase the number of plants after the termination of the pandemic confinement period. Similarly, 75.2% of the householders expressed their reluctance to invest in plant purchases during the confinement period of the pandemic. It is worth noting that 52% of the respondents reported spending more time taking care of plants at home during the confinement period and 62.5% expressed their desire to devote more time to taking care of plants at home once normality was resumed. 20 Table 5. List of detected differences in responses concerning the respondents’ emotional state between the total collected questionnaire data and the four major contributing countries: Spain, Italy, Brazil, and Greece. The fonts in bold represent the different responses among countries compared with those of the total sample. Questions and Factors Total Questionnaire Sample ------------------------- Four major contribut ing countries (82.4% of the responses) ------------------------- Spain (19.6%) Italy (9.4%) Brazil (29.6%) Greece (23.8%) Age group Negative emotions were more frequent in 18-25 year olds Negative emotions were more frequent in 18-25 year olds Emotional state indifferent considering age Negative emotions were more frequent in 18-25 and 26-40 year olds Emotional state indifferent considering the age Receiving natural light indoors More frequent negative emotions with low levels of natural light indoors More frequent negative emotions with low levels of natural light indoors Emotional state not influenced by the level of natural light indoors More frequent negative emotions with low levels of natural light indoors More frequent negative emotions with low levels of natural light indoors Frequency of visiting green spaces prior to the crisis Negative emotions for respondents who visited green spaces monthly or less than once per month Emotional state indifferent considering frequency of visiting green spaces Emotional state indifferent considering frequency of visiting green spaces Negative emotions for those who used to visit green spaces monthly Emotional state indifferent considering frequency of visiting green spaces House size Negative emotions were more frequent in residents living in small-sized houses (<40 m 2 ) Negative emotions were more frequent in residents living in small-sized houses (<40 m 2 ) Negative emotions were more frequent in residents living in small-sized houses (<40 m 2 ) Negative emotions were more frequent in residents living in houses of <40 m 2 and also from 40 to 70 m 2 Emotional state indifferent considering house size Gender Negative emotions were more frequent in women Negative emotions were more frequent in women Emotional state not affected by gender Negative emotions were more frequent in women Negative emotions were more frequent in men 21 Number of plants indoors Negative emotions more frequent in responders having no or less than 4 plants Emotional state not affected by the number of indoor plants Emotional state not affected by the number of indoor plants Negative emotions more frequent in responders with no indoors plants Emotional state not affected by the number of indoor plants 22 3.5. Living walls as an option for increasing indoor vegetation The questionnaire included a short description of living walls accompanied by a relevant photograph depicting their indoor application in order to concomitantly determine participants’ knowledge and inform those who were not familiar with the specific technology. It was determined that only 16.1% of the total participants were not familiar with the living wall concept. In a further elaboration for evaluating participants’ perception in terms of the potential applicability of living walls, 51% agreed and 25.5% strongly agreed with the statement that living walls could be considered as an alternative greening technology able to provide increased vegetation at home by occupying less space, while only 5% disagreed or strongly disagreed. However, most participants had difficulty relating to the application of living walls. Among the main reasons that discouraged them from a living wall installation indoors were: maintenance, which was reported by 52% of the participants, potential dampness problems (44%), concerns of insects or presence of other animals within the house (39.5%), and anticipated construction and installation costs (32.0%). 3.6. Preference regarding different quantities and types of greening in the buildings In all cases, the option without vegetation (A) was the least preferred (Fig. 7). In indoor spaces, few (5-7) plants in pots were desirable (option B), although in the case of Room 1, the option regarding many plants and a living wall (option D) was also well-rated. Contrary to the indoor aesthetic perception, the arrangement on the outdoor balcony which included plants and a living wall was the preferred choice, although the scenario without a living wall but with many plants was also well-accepted, with 23% of the respondents selecting it as the 1 st option and 42% as the 2 nd . 23 Figure 7. Preferences regarding the level of vegetation for two indoor rooms and a balcony, rated from the most preferred [1] to the least preferred [4]. (A) No vegetation, (B) few plants, (C) many plants, (D) many plants and living walls. A lower number denotes a higher preference for each option within each column. 4. Discussion Previous studies have concluded that contact and interaction of humans with nature has a positive impact on their health and well-being (Grinde & Patil, 2009; Kim & Miller, 2019; Navarrete-Hernandez & Laffan, 2019). In our study, 89.5% of the respondents were strongly in favour of the necessity of open green spaces for their psychological well-being, which is in agreement with the results of several other researchers such as Buchel and Frantzeskaki (2015), Luck et al. (2011), and Mavoa et al. (2019). In our study, psychological benefits seemed to be linked not only to the presence of vegetation, but also to a combination of factors such as the possibility of doing exercise in open spaces, enjoying fresh air, and relaxing or connecting with other people (Chiesura, 2004; Wang et al., 2020; Wood et al., 2017). However, there is currently no available literature explaining the feelings and their impact on people’s Mean scores : 3.3 2.0 2.5 2.2 3.2 1.9 2.4 2.6 3.5 2.4 2.3 1.9 24 psychological state when access to green spaces is not a feasible option. The COVID-19 pandemic emerged as a unique and global crisis that deprived people worldwide from the possibility of visiting public green spaces for a prolonged period of time, which extended to more than 6 weeks. Therefore, under the specific circumstances, a unique opportunity is provided to conduct research on the extent of the impact of nature’s substitutes within a household / on a household’s living standards. The respondents’ view with regard to house vegetation and its impact on their emotional status under confinement conditions is expected to be a clearer and a standalone procedure, which is exempted from everyday interactions and interventions. The primitive human urge to employ natural elements in the household is reflected in the tradition and habit of introducing indoor and outdoor plants at home. In the current study, only 3.3% of the participants reported not having indoor plants in their home. However, there was a clear preference for outdoor rather than indoor vegetation, in the form of front gardens, balconies, backyards, and terraces. Despite the latter, the statistical analysis of the data revealed a significant influence of indoor plants on the reported emotional state. By contrast, although having more plants outdoors did not seem to affect the respondents’ emotional state, this could be attributed to the inherited positive interaction between outdoor space (irrespective of having plants or not) and the amelioration of the mood. The majority of the respondents (73.7%) agreed that having vegetation at home positively contributed to their mood during the COVID-19 confinement period, while only 3.5% disagreed. This seems to be reinforced by the frequency of self-reported positive (calmness, optimism and cheerfulness) and negative (stress, sadness, fearfulness and depression) emotions during the COVID-19 crisis among those with many (more than 7 plants), some (3-7 plants) and no or very few (less than 3) indoor plants at home. 25 A similar percentage believed that, in general, having indoor vegetation was favourable for their psychological well-being. In this sense, when people report an overall improvement of their well-being whenever indoor plants are present, they are actually experiencing the physiological manifestations of psychological effects (Fjeld, 2000), similarly to influences of the natural environment over the subconscious parts of the brain in ways that cannot easily be described (Grinde & Patil, 2009). The production of mental health benefits resulting from the interaction between humans and nature may occur through multiple psychological causal mechanisms and pathways, including reduction of stress or replenishment of cognitive capacities (Bratman et al., 2019). The positive effects produced by the presence of indoor plants may be attributed to the visual appearance of plants, since affective responses to visual stimuli that are deemed aesthetically pleasant could contribute to the release of tension (Grinde & Patil, 2009). Some studies point out that the effect of vegetation on human psychology differs according to demographic variations such as gender and age (Aydogan & Cerone, 2020; Bratman et al., 2019). As an example, Hennigan (2010) reported that men were more positively affected by displays of indoor vegetation than women. However, the introduction of flowering indoor plants had a more positive effect on women rather than men. In our study, women experienced negative emotions more frequently than men. However, no gender differences were detected with regard to the positive influence of house plants on the respondents’ emotional state during the health crisis. Regarding the age groups, although older people felt negative emotions less frequently, they acknowledged a higher positive influence of home plants on their emotional welfare. More specifically, while 84% of respondents between 66- and 80-years agreed that vegetation at home assisted their emotional well-being, only 70% of respondents who were less than 40 years had the same view. 32 ornamental plant producers during the COVID-19 pandemic. In many different parts of the world, sales of ornamental horticultural products decreased or ceased, since horticulture is considered as a non-essential service and most of the consumers were forced to focus on essential purchases only. Although online and delivery sales were encouraged (Reis et al., 2020), internet sales represented only a small portion of the whole potential market (AIPH, 2020b). The reduction in the sale of ornamental plants was further aggravated by the closure of borders, reduction of available transportation and interruption of landscaping projects (AIPH, 2020a). Nevertheless, the shift in the participants’ perception regarding the benefits of having plants at home can generate a motivation for buying more plants after the crisis. This would be a very positive outcome for the ornamental horticultural industry since the strategies to stop the spread of COVID-19 had a far-reaching effect by partially or completely closing gardens centres, flower shops, and floriculture farms all around the world. 5. Conclusions The present study shows that, according to the majority of participants, vegetation in indoor living spaces positively influenced their emotional well-being during the confinement period. However, they preferred low levels (5-7) of indoor plants for their houses, while the participants made a wider use of the outdoor spaces of their houses for establishing their plants. The respondents’ appreciation and the presence or use of plants in their living spaces was influenced by the COVID-19 restrictions, with more than half of the participants being willing to host more plants at home and allocate more time for their maintenance during the confinement period. The living wall systems were appreciated by the respondents as an option to increase the number of plants at home and there was a demonstrated preference for using them mainly outdoors (e.g., on balconies). Further research is suggested in order to further 33 correlate certain specific characteristics of the population with the impact of indoor greening capacity to alleviate stresses resulting from confinement situations. 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