216 American Scientific Research Journal for Engineering, Technology, and Sciences (ASRJETS) ISSN (Print) 2313-4410, ISSN (Online) 2313-4402 © Global Society of Scientific Research and Researchers http://asrjetsjournal.org/ An Exploratory Study of Gardening Practices and Ornamental Plants in Khartoum State, Sudan Elsir A. Salih a∗, Khawla Abdullah Mohammed b a,b Department of Biology, Faculty of Education, Alzaeim Alazhari University, Khartoum, P. O. Box:1432, Khartoum North 1331, Sudan a Email: elsir.adam@aau.edu.sd b Email: khawlamajed92@gmail.com Abstract In Sudan, as in many parts of the world, ornamental plants are gaining a growing interest. This study aimed to shed light on gardening (horticulture) and ornamental plants in Khartoum State, Sudan by focusing on gardening practices, verifying people's awareness of the environmental role of these plants, and studying species diversity within major ornamental groups namely; cacti and ornamental palms. Data were collected through structured questionnaires with both gardeners and the general public. The results showed that gardening practices as well as interest in ornamental plants have grown rapidly in recent decades and that most of the gardeners belong to young adults (21-40) with a sex ratio of 1: 1. Aesthetic values and combating desertification have been reported as the most important roles of ornamental plants. The remarkable diversity of ornamental plants in cacti and royal palms is attributed to the adaptive ability of their species to grow in the hot and dry environment of the study area, the simplicity of their reproduction and their profitable sales. Key words: Sudan; ornamental plants; gardening practices; environmental roles. 1. Introduction Ornamentals constitute a group of plants employed by humans throughout history [1]. Ornamental plants can be defined in many ways but the main criterion of all is their aesthetic value i.e. they are plants primarily grown for their beauty either for screening, accent, specimen, color or aesthetic reasons. ------------------------------------------------------------------------ * Corresponding author. American Scientific Research Journal for Engineering, Technology, and Sciences (ASRJETS) (2021) Volume 78, No 1, pp 216-225 217 The value of ornamental plants is not only aesthetic and decorative, but also of great environmental and economic through the production of cut flowers and contribute to the production of medical and aromatic materials [2]. Urban trees improve air quality, cool local air temperatures, filter and retain storm water, sequester carbon, and contribute to healthier and more beautiful cities. Common ornamental features include leaves, scent, fruit, stem, and bark [3]. Sudan is characterized by its climatic conditions that are very suitable for various ornamental plants. In addition, the difference between the different parts of the country in terms of soil types and climatic factors resulted in a great diversity of ornamental plants, both wild and cultivated. All this helps in establishing public and private gardens, to give our lives happiness and pleasure [4]. Recently, human interest in growing ornamental plants has increased all over the world. Ornamental nurseries in Sudan have become a general feature on the sides of most streets, especially in major cities, but despite this and according to our best knowledge, scientific studies that investigate this area in Sudan are lacking. This is perhaps the motivation for conducting the present study. This study aimed to shed light on gardening practices in Khartoum State, to verify people's awareness of the environmental importance of these plants, and to study the diversity of plant species within two main ornamental groups, namely, cacti and ornamental palms. 2. Materials and Methods 2.1. The study area Khartoum, the capital of Sudan, is located between latitudes 15º26’ and 15º45’ N and longitudes 32º25’ and 32º40’ E, at an altitude of 405.6 m above sea level. The terrain is generally flat or gently sloping, only interrupted by occasional hills of rocky outcrops while sand dunes provide a gently undulating topography. The White Nile has a much lower gradient that the Blue Nile and consequently its terraces rise far more gently [5]. The main climatic conditions of Khartoum are conditioned by its location on the southern fringes of the Sahara. The city experiences four climatic seasons [6]. The winter season extends from mid-November to March, with clear skies, cool and dry air from the north-east, a minimum temperature ranging between 8ºC and 10ºC which falls to 5ºC during night, and maximum temperatures varying from 23ºC to 25ºC, and a relative humidity which may sometime be as low as 20 per cent. The hot, dry summer season is well in place by the end of March. The maximum temperatures may exceed 45ºC by the end of May. Weather instability is indicated by the recurrence of dust storms. The rainy season covers the period from July to September, with August being the rainiest month, Generally, annual rainfall ranges between 110 and 200 mm, but a minimum of only 4 mm was recorded in 1984 and an exceptional maximum of 420 mm in 1988. A short, hot (about 40ºC) transitional season occurs between mid-September and the beginning of winter. This changeover season from south-westerly to north- easterly winds is accompanied by dust storms. 2.2. Data collection The study was conducted during the years 2017 and 2019 in Khartoum State, which consists of three towns: Khartoum, Omdurman, and Khartoum North. Ten nurseries were randomly selected in each of the three towns of the state to make a total of 30 nurseries. The data were collected through structured questionnaires with the operators (gardeners and nursery owners). Pilot visits were made to a few nurseries to validate the questionnaire American Scientific Research Journal for Engineering, Technology, and Sciences (ASRJETS) (2021) Volume 78, No 1, pp 216-225 218 and improve any weakness. The questionnaires focused on gardening practice - in terms of the gardeners' gender, age groups, and experiences -, the environmental roles of ornamental plants, and the diversity of species within two ornamental groups: cactus and ornamental palms. Special emphasis on these two groups came from the fact that they are the most abundant in term of species in gardens as observed during the pilot visits. Besides gardeners, 30 local families were questioned in order to investigate their perception about the environmental roles of ornamental plants and compare their results with those of gardeners to see if there is any difference. All the distributed questionnaires were answered, and returned. All the obtained data were tabulated and subjected to statistical analysis using Microsoft Excel version 2013. 3. Results and discussion 3.1. Gardening practices According to gender, the results of the survey showed that males and females are equally involved, i.e., with the same ratio (15 M :15 F), in operating and managing ornamental nurseries. This is in agreement with the finding of [7] and [8], both in Nigeria, who reported the involvement of both genders in the practice, but with varying ratios (32 M: 68 F) and (73 M: 27 F) respectively. As shown in Figure (1), gardeners belong to different age groups ranging from 20 to 100 years, but the youth group (21 to 40 years) dominates significantly (67%). This great superiority of the youth category may seem reasonable in light of the fact that the elderly, especially those over the age of seventy, are physically less able to engage in such a practice. However, the finding may indicate that this practice could satisfy the financial aspirations of these young people who are at the beginning of their career. This result supports the finding of [7], who reported that respondents with the age group (31 to 40 years) were predominant in gardening practice in Southern Edo State in Nigeria. Figure 1: Age distribution of respondents 0 5 10 15 20 25 21 to 40 41 to 60 61 to 80 81 to 100 P e rc e n ta ge o f re sp o n d e n ts Age distribution American Scientific Research Journal for Engineering, Technology, and Sciences (ASRJETS) (2021) Volume 78, No 1, pp 216-225 219 In regard to the field of specialization (education background), the results illustrated that 25 out of the 30- informants (83%) are specialized in this field i.e., horticulturists or at least they have education background of plant sciences. This means that education is a major factor in developing this culture in the society. The rest (17%) came from other different backgrounds and most of them were attracted to this practice because of the involvement of some of their relatives or friends. With regard to work experience, as shown in Figure (2), there is a clear variation in years of experience with most informants falling in the range of 1-10 years. It is clear that this difference is mainly due to the difference in the ages of the respondents, as most of those with more than 10 years of experience are elderly, while most of those with less than that are young graduates. But these extended years of experience confirm an important fact that this practice is not a temporary practice that people resort to as a secondary option, but rather a permanent investment. Figure 2: Years of experience of respondents According to the informants, and as shown in Figure (3), there is a clear increase in the number of gardens that were established in recent decades compared to the past. This was evident in the high percentage of gardens founded after the year 2000 (77%) compared to those established before. This tremendous trend in this practice may explain an increasing interest among local people in ornamental plants and the overspread of this culture in the society. This result is in agreement with several ethno-botanical studies (e.g., [9]; [10]; [11]) that link the recent popularity of urban gardening to the shift from rural mode of life to more modern life style particularly in areas where the influence of West European culture is quite strong and hence the ideas of ecology and community are accepted. 0 2 4 6 8 10 12 14 1 to 10 11 to 20 21 to 30 31 to 40 P e rc e n ta ge o f re sp o n d e n ts Years of experience American Scientific Research Journal for Engineering, Technology, and Sciences (ASRJETS) (2021) Volume 78, No 1, pp 216-225 220 Figure 3: The pattern of growth in garden numbers over time 3.2. Diversity of ornamental plants For the two ornamental groups under study, i.e., the Cacti and Royal palms, a total of 36 ornamental species were identified (22 cacti species and 14 ornamental palm species). 3.2.1. Cacti and Succulent According to Fig. 4 and Table 1, all of the 22 reported ornamental species are distributed among 10 families with clear superiority of the species that belong to Agavaceae (26%) and Cactaceae (20%). Table 1 also indicates that most of these species are shrubs and that the most widely used method of propagating them is by offsets. Among the Agavaceae, the species of the two genera: Agave and Yucca are the most common as they represent the most abundant species in over 70% of the surveyed gardens, while the abundance of other species varies from garden to garden. On the other hand, the most abundant species of the Cactaceae family in gardens are those of the genus: Cereus by 40%. The predominance of Agavaceae and Cactaceae over other families can be attributed to their high ability to adapt well to growing in the hot and dry environments that characterize the study area "Khartoum". Other reasons for their dominance, as reported by gardeners are: the simplicity of the methods of their propagation, as most of them can be propagated vegetatively by offsets, cutting, or both methods (table 1), and most importantly, their high commercial value because they are among the best-selling ornamentals in the study area. The wide distribution and dominance of ornamental succulent was reported from many parts of the world. According to [12], Cacti are conspicuous elements of the Western hemisphere; they have long attracted attention due to their peculiar biology, and have maintained close relationships with local settlers. Also, as reported in [13] and [14], cacti are distributed in nearly every ecological region in the Americas, even in rainforests. However, the highest diversity is concentrated in arid and semi-arid regions located between 35º north and south latitudes, and from sea level to 5,000 m. According to [15] Cactaceae is endemic to the Western hemisphere, except for Rhipsalis baccifera which is also found in Africa and Asia, it comprises 124 genera and 1,427 specie and the most usage propagation method among the species of the group American Scientific Research Journal for Engineering, Technology, and Sciences (ASRJETS) (2021) Volume 78, No 1, pp 216-225 221 1 1 1 1 2 2 3 5 6 0 1 2 3 4 5 6 7 Apocynaceae Aizoaceae Asclepiadaceae Crassulaceae Liliaceae Aloeaceae Euphobiaceae Cactaceae Agaveaceae Number Of Species Fa m e lie s is the offsets and common growing habit is shrub. Figure 4: Distribution of cacti species among plant families Table 1: List of ornamental plants reported in the cacti group and some of their characteristics. Scientific name Common name Family Main Mode of Propagation Growth habit Aloe arborescens Krantz aloe Aloeaceae Off-sets Shrub Aloe varigata Tiger aloe Aloeaceae Off-sets Shrub Agave Americana Centry plant Agaveaceae Off-sets Shrub Agave attenuate Lionstail, Foxtail Agaveaceae Off-sets Shrub Opunitaficus-indica Pirckly pear Cactaceae Cutting Shrub Euphorbia milii The crown of thorns Euphobiaceae Off-sets Shrub Eupgorbia schottiana Lion’s tail Euphobiaceae Off-sets Shrub Euphorbia arahaka Angel Euphobiaceae Off-sets Shrub Kalanchoe marmorata Penwiper Crassulaceae Offsets Shrub Sansevieria trifasciata Snake plant or mother-in- low’s tonghe Agaveaceae Off-sets and Cutting Shrub Sansevieria cylindrica Snake plant or African spear Agaveaceae Off-sets and Cutting Shrub Yucca aloifolia Aloe yucca Agaveaceae Off-sets Shrub Yucca gloriosa Adam’s needle Agaveaceae Off-sets Shrub Cereus chalybaeus Night-blooming cereus Cactaceae Off-sets Cereus peruvianus The Peruvian apple cactus Cactaceae Off-sets Shrub or tree-like Echinocacereus undatus Dragon fruits Cactaceae Off-sets Shrub Stapelia gigantean Carrion plant or zuluginant Asclepiadaceae Offsets and Cutting Shrub Mesembryanthemum Ice plant Aizoaceae Cutting Shrub Gasteria maculate Ox-tongue Liliaceae Off-sets and cutting Shrub Haworthia fasciata Zebra cactus Liliaceae Cutting Shrub Mammillaria compressa mother of hundreds Cactaceae Off-sets Shrub Adenium obesum The desert rose Apocynaceae Off-sets and cutting Shrub American Scientific Research Journal for Engineering, Technology, and Sciences (ASRJETS) (2021) Volume 78, No 1, pp 216-225 222 3.2.2. Ornamental Palms As shown in table (2), 14 ornamental palm species were listed. All the species belong to only two plant families, Arecaceae and Cycadaceae,with a clear superiority of the members that belong to Arecaceae family (12 species). The most abundant species in term of number/garden was observed to be: Oreodoxaregia. The large dominance of Arecaceae species may be attributed mainly to the large number of species that belong to this family, however, informants believe that the high adaptability of this species to grow in the hot and dry environment that characterizes the study area, Khartoum State, along with their economic profitability may be other reasons. This finding is in line with that of [16] in central-western Brazil, who attributed the high value of this family to the diversity of its species, its occurrence in a wide range of habitats, and its status as an integral part of the culture and family-based economy of many traditional and non-traditional societies. Another survey conducted by [17] in Ghana showed that All nurseries surveyed produced at least 15 different species of plants belonging to various families, the Arecaceae family was the most popular and had the greatest number of species. Unlike the listed cacti and succulents, which are mostly shrubs, most of the listed species of this group are trees and the most common method of their reproduction is seeding as in Table 2. Table 2: List of ornamental plants reported in the royal palm group and some of their characteristics. Scientific name Local name Family Main Mode of Propagation Growth habit Oreodoxa regia Royal palm Arecaceae Seeds Tree Ravenala madagascariensis Travellers palm Arecaceae Off-sets Tree Livistona chinensis The Chinese fan palm or fountain palm Arecaceae Off-sets Shrub Washingtonia filifera The fan palm Arecaceae Seeds Tree Chamaedorea elegans Parlour palm Arecaceae Seeds Shrub or tree- like Areca alicae Areca nut palm or betal Arecaceae Off-sets Tree-like Kentia belmoreana Howeaforsteriana Arecaceae Seeds and Off- sets Tree Sabal palmetto Cabbage-palm or sabal palm Arecaceae Seeds Tree Phoenix canariensis Canary palm Arecaceae Seeds Tree Hyophorbelagenicaulis Bottel palm or palmist gargoulette Arecaceae Seeds Tree Rhapis excels Broadleaf lady palm or bamboo palm Arecaceae Seeds Shrub Caryotalmitis The clustering fishtail palm Arecaceae Seeds and Off- sets Tree Cycas revolute Sago cycad Cycadaceae Seeds and Off- sets Shrub Zamia decumbens Sinkhole cycad Cycadaceae Off-sets Shrub 3.3. Roles of Ornamental Plants in Environment As shown in Figure 4, both the two groups of informants i.e., gardeners and local inhabitants, recognized the importance of the environmental roles played by ornamental plants. The difference between the two groups is American Scientific Research Journal for Engineering, Technology, and Sciences (ASRJETS) (2021) Volume 78, No 1, pp 216-225 223 clearly very slight in terms of the overall ranking of these environmental roles. In both cases, aesthetic value, combating desertification, and air improvement were reported as being the most important. However, aesthetic value was ranked first by the local population, while gardeners considered combating desertification as the most valuable. On the other hand, windbreaks and carbon sinks were ranked at the bottom of the list, noting that the latter received very little attention from local residents compared to gardeners. These slight differences between the two groups regarding the environmental roles of ornamental plants may be due to differences in educational background since most gardeners have a botanical background and can thus assess the matter from a more scientific perspective. Several environmental studies from other parts of the world have reported on the important environmental roles that ornamental plants play e.g., [18] revealed that the respondents in Southwestern Nigeria claimed that ornamental plants arrest dust, supplies oxygen and help as wind break and believed that plants reduce erosion and protect the environment from other natural hazard. According to a study conducted by [19] in India, the use of ornamental plants, herbaceous trees and greenery as natural filters for air pollution reduces respiratory disease mortality rates and reduces hospital visits. Figure 5: Environmental Roles of ornamental plants 4. Conclusion This study concluded that awareness and interest in ornamental plants has increased in Khartoum State during the past two decades, which prompted many people of both genders and different age groups to invest in this field. Aesthetic values and combating desertification have been reported as the most important roles of ornamental plants. The remarkable diversity of ornamental plants within cacti and royal palms was attributed to the adaptive ability of their species to grow in the hot and dry environment of the study area, the simplicity of their reproduction and their profitable sales. 5. Recommendation This study recommends further scientific studies in this field to bridge the gap in information about ornamental 0 5 10 15 20 25 Aesthetic value Combating desertification Air improvement Windbreak Carbon sinks Fr e q u e n cy Roles of ornamental plants Gardeners Inhabitants American Scientific Research Journal for Engineering, Technology, and Sciences (ASRJETS) (2021) Volume 78, No 1, pp 216-225 224 plants and horticultural practices in Khartoum State, in order to provide a database upon which future plans and strategies can be based. Acknowledgement The authors sincerely thank Dr. Elnasri Mutwali, Department of Biology at Alzaeim Alazhari University, for his encouragement throughout the study period. We also thank the gardeners and locals in the study area for their positive attitudes and cooperation. References [1]. Hurrell J, A. “Ornamental Plants”, National University of La Plata, 202 publications (171-173), 2016. [2]. 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