1. Introduction

　　1.1 Research Background

　　Fuzhou is located on the east wing of the Daiyun Mountains, facing the sea and leaning against the mountains. The Minjiang River runs through it, and the lower reaches are the Fuzhou Basin. The interior of the basin is an alluvial marine plain, and the urban area is in the center of the basin. The north and east are mountains and hills, and the south is a plain. Fuzhou is located in the middle and low latitudes and is close to the Pacific Ocean. It has a subtropical marine monsoon climate, which is warm and humid, with abundant rainfall, evergreen all year round, and a pleasant climate. The average annual temperature is 19.6℃, the average annual precipitation is 1342.5 mm, the frost-free period is 326 days, the average annual sunshine is 1700-1980 hours, the average annual rainy days are 130-170 days, and the annual relative humidity is 77%.

　　1.2 Research status

　　Plant configuration is the theme of greening and the main theme of garden planning and landscape design. Plant configuration in ancient gardens The earliest records of plant configuration in ancient gardens can be found in books on flower catalogs and flower art in the Song Dynasty. They were discussed in the "Qunfangpu", "Yuanye" and "Changwuzhi" of the Ming Dynasty. There are more detailed descriptions in the "Guangqunfangpu" and "Huajing" of the Qing Dynasty. Judging from these written records and the gardens and ancient trees that have been preserved to this day, the plant configuration in ancient gardens has the following characteristics: the garden focuses on appreciating the individual beauty of plants, mostly in solitary planting, and rarely trimming; learning from nature, simulating natural plant landscapes into the garden; liking to concentrate on planting a certain type of plant with characteristics or that is loved by the masses, forming a special garden. In the long history of garden construction, the procedure of garden plant configuration has been formed, such as planting plums around the house, willows on the bend of the embankment, locust shade in the courtyard, moving bamboos in front of the window, hanging kudzu and hanging vines, etc., all of which reflect the unique style of garden plant configuration.

　　Modern plant configuration has made new developments. Hao Yuting mentioned in "Six Major Flaws in Residential Greening Design": "The planting and artistic configuration of plants should be based on the characteristics of the plants and the special ecological environment. The configuration of plants in residential areas should focus on the construction of complex structure plant communities of trees, shrubs and grasses, maximize the green volume per unit area, give play to ecological benefits and functions, and increase ecological effects." Xue Hen mentioned in "Configuration of Garden Plants" that in garden design, "there is no beauty without quantity" and that the beauty of plants sometimes needs to be reflected through groups.

　　At present, greening is flourishing in units, communities and courtyards in Fuzhou. We will intensify the greening construction and garden-style creation work in residential areas and units. The construction of residential areas and units must strictly follow the regulations of more than 30% greening rate in new areas and more than 25% in old cities [1] to leave enough land for greening, strengthen supporting greening construction and management, and implement a tracking and feedback system. Plant configuration is carried out according to the principle of "suitable trees for suitable places and adapting to local conditions" to form green landscapes with unique characteristics, so that the protection of ancient trees and famous trees can achieve the three synchronizations of "tree body, habitat and landscape protection".

　　According to reports, in the future, the proportion of trees in Fuzhou's urban residential areas will be appropriately increased, so that the right trees are suitable for the right places, with regional, native and local tree species as the main focus, while rationally introducing optimized foreign tree species to enrich and optimize the composition of garden greening tree species; rationally determine the proportion of evergreen trees, deciduous trees, trees, shrubs, fast-growing trees, mesophyll trees, and slow-growing trees. At present, 12 tree species have been determined as the keynote tree species for Fuzhou's urban greening, including camphor trees, osmanthus fragrans, banyan trees, large-leafed banyan trees, mangoes, litchi, longans, erythrina trees, kapok trees, Bauhinia scabra, false betel nuts, and cattail palms; 29 tree species such as banyan trees and metasequoia are backbone tree species.

　　1.3 Research significance

　　Plants are one of the four major elements of gardening. British gardener B. Clauston proposed: "Garden design is ultimately the design of plant materials, and its purpose is to improve the ecological environment of mankind. Other contents can only play a role in an environment with things." Plant configuration is to use plant materials combined with other materials in the garden, according to the growth law and site conditions of garden plants, adopt different composition forms, form different garden spaces, and create various garden landscapes to meet people's needs for viewing and recreation. In garden design, plant configuration occupies an important position and is an important part of garden design. Plants are the main body of the garden, and plant configuration is the main theme of garden design and landscape construction. Different residential areas have unique styles in plant configuration, reflecting the diversity of plant species in nature, and strive to enrich tree species without being messy. Good planting design can become a clear landmark in the residential area.

　　Therefore, the analysis of plant configuration in residential areas of Fuzhou City is of great significance for the planning and construction of urban residential areas. It is also lacking in most cities, so it is worth studying.

　　2. Current status and development trend of plant configuration in residential areas of Fuzhou

　　Through field investigations in five residential areas, including Andan Community, Mudanxiang Garden, Xiangxie Liju, Jinxia Community, and Xinqinting Community (see Appendix 1 for details), and based on literature review, it is concluded that the current plant configuration in Fuzhou's residential areas has the following characteristics and lists the best plant configuration schemes currently used in Fuzhou's residential areas. Through comparative studies, their commonalities and development trends are found.

　　2.1 Advantages and disadvantages of plant configuration in five residential areas of Fuzhou

　　2.1.1 Andan Community

　　Advantages: (1) A large number of native tree species in Fuzhou are used, such as banyan, white magnolia, camphor, kapok, etc.

　　(2) Use colorful and trimmable hedge plants, such as Ligustrum lucidum, Berberis rubrum, and Boxwood to trim into various geometric patterns.

　　Disadvantages: (1) The plant species used in plant configuration are single

　　(2) Ignoring the “people-oriented” approach, such as using green spaces as isolation zones, neglecting the convenience of people’s lives, and a two-minute journey may take more than ten minutes.

　　2.1.2 Peony Garden

　　Advantages: (1) The entire plant planting has a focus and characteristics, with changes in unity and unity in richness.

　　(2) The overall layout is relatively good

　　(3) The artificial plant community is scientifically configured, reflecting the cultural characteristics and local charm of the garden.

　　Insufficient: (1) Maintenance work is not good enough

　　(2) The entire plant landscape shows signs of fading

　　2.1.3 Xiang Xie Li Ju

　　Advantages: (1) Suspended greening from top to bottom and climbing greening from bottom to top

　　(2) The combination of herbaceous and woody flowers with different flowering periods ensures that the green space can present a good landscape effect all year round.

　　Disadvantages: (1) The plant configuration is flat and the dynamic perspective effect of the plant landscape on the facade is not good

　　(2) Plants are planted too randomly

　　2.1.4 Jinxia Community

　　Advantages: (1) Application of city flowers and trees

　　(2) Plant configuration should be clearly layered and focus on color blocks to form a multi-layered mixed greening pattern with trees as the main component and trees, shrubs, vines, flowers and grasses combined.

　　Insufficient: (1) Insufficient consideration is given to the cultural function of the landscape. (2) The green coverage rate of the entire community is not very high.

　　2.1.5 Xinqinting Community

　　Advantages: (1) The plant configuration changes with the four seasons, making it synchronized with the residents’ life patterns of spring, summer, autumn and winter.

　　(2) Based on the ecological habits of plants

　　Disadvantages: (1) Paving materials are too expensive, and the ecological effects of green plants were not taken into consideration during paving.

　　(2) The lawn area is large, and the ratio of grass to trees and shrubs is not harmonious

　　(3) Immediate effects and long-term benefits are not coordinated

　　(4) Perennial flowers and aquatic plants are less used.

　　2.2 Commonalities of plant configuration in residential areas of Fuzhou

　　(1) Highlight seasonal phases

　　Fuzhou is dominated by evergreens, flowers blooming all year round, and coconut trees of the southern tropical zone. In the residential area, there are magnolias, peach trees, plums, forsythia, winter jasmine, lilacs, and spireas in spring; lotus, albizzia, Koelreuteria paniculata, American trumpet creeper, crape myrtle, and hibiscus in summer; glutinous rice strips, Chinese roses, cotinus coggygria, maple, maple bark, Pistacia chinensis, yam, purple-leaf plum, purple-leaf barberry, and ground ivy in autumn; and evergreen pines and cypresses and vigorous banyan trees in winter.

　　(2) Plant arrangement: When selecting tree species, the local environment, climate, and city history and culture should be taken into consideration.

　　The top ten roadside trees in residential areas are small-leafed banyan, mango, Bauhinia, Livistona, big-leafed banyan, alpine banyan, cinnamon, camphor, yellow-flowered locust, and queen palm. The total number of small-leafed banyan and mango accounts for 50.73% of the total number of all roadside trees. These two plants determine the main tone of road greening in residential areas in Fuzhou.

　　(3) Plants are arranged according to the principle of "suitable trees for suitable places and adapting measures to local conditions" to form green landscapes with unique characteristics, so that the protection of ancient and famous trees can achieve the three synchronizations of "protection of the tree, habitat and landscape".

　　2.3 Partial plan of plant configuration in residential areas of Fuzhou

　　2.3.1 Common tree species in each layer of plant configuration

　　(1) Common tree species in the upper layer: Ficus microcarpa, Ficus microcarpa, Eucalyptus, Acacia taiwanensis, Bauhinia, Poinciana, Hibiscus tiliaceus, Casuarina, Platanus, Betula chinensis, Masson pine, Royal palm, Coconut, Livistona palm, Jackfruit, Almond, Jacaranda, Jacaranda, Pyrola, Crape myrtle, Litchi, Pot rack, Melaleuca alternifolia, Mango, Mango tree, Butterfly fruit, Castanea chinensis, White orchid, Mahogany, Kapok, Syzygium wilfordii, Lotus, Autumn maple, etc.

　　(2) Common tree species in the middle layer: bamboo cypress, long-leaved bamboo cypress, Torreya grandis, Cephalotaxus fortunei, Torreya grandis, Podocarpus, red fennel, Milan, Murraya osmanthus, red-backed laurel, hawk melon flower, camellia, oil tea, large-leaf tea, osmanthus, Michelia, Pittosporum, Nandina domestica, Gardenia jasminoides, Water Gardenia jasminoides, Fathom brown, winter red, hydrangea, Berberis, Mahonia, hairy jasmine, tiger thorn, Yunnan yellow jasmine, peach-leaf coral, bone, callicarp, horse honeysuckle, Ardisia, magnolia, sword-leaved ironwood, soft-branched thorny palm, swallowtail palm, areca palm, palm bamboo, golden chestnut orchid, cordyline, snow in June, umbrella tree, golden chestnut orchid, three-medicine betel nut, etc.

　　(3) Understory vegetation: Curculigo, Curculigo macrophylla, Aspidistra, Water banana, Tiger tail orchid, Chinese ivy, Ivy, Long-stalked syngonium, Trachelospermum, Schisandra chinensis, Calla lily, Water tower flower, Purple-backed arrowroot, Lucky grass, Acorus calamus, Guangdong Dieffenbachia, Creeping pot grass, Red-flowered Oxalis, Carpet grass, Green cloud grass, Corydalis, Corydalis, Alpinia officinalis, Alpinia variegata, Begonias, Duck toe grass, Water tower flower, Red-backed laurel, Spider orchid, Schefflera arborvitae, Clam orchid, etc.

　　2.3.2 Plant community patterns suitable for application

　　(1) Bauhinia scabra - Camellia - Alocasia ovata + Alpinia officinalis - Herba Lycopodii

　　(2) White Orchid - Camellia oleifera + Kohlrabi - Tigertail Orchid

　　(3) Melaleuca alternifolia - Osmanthus fragrans - Ophiopogon japonicus

　　(4) Livistona chinensis - Nandina domestica + Pittosporum tobira - Bigleaf Fairywort + Red Oxalis,

　　(5) Nanyang Ying - Hawk's Claw + Michelia + Camellia - Carpet Grass

　　(6) Eucalyptus macrophylla - Longleaf cypress - Brown bamboo - Carpet grass

　　(7) White orchid - Large-leaf Milan - Pearl orchid

　　(8) White orchid + yellow orchid + Magnolia + Magnolia grandiflora + Schima superba + Schima superba - Night Jasmine + Magnolia - Creeping pot grass + Acorus calamus

　　(9) Pink bamboo - Alsophila spinulosa - Carpet grass

　　(10) Half Maple - Winter Red + Hairy Jasmine - Carpet Grass

　　(11) Pink bamboo - Alsophila spinulosa + Alsophila spinulosa - Carpet grass

　　(12) Pot rack - Red-backed osmanthus - Carpet grass

　　(13) White orchid + Kapok + Crape Myrtle - Grapefruit - Red Plumeria + Oleander - Hibiscus + Croton + Hawk's Claw + Indigo - White Lotus + Purple-backed Dieffenbachia + Spotted Duck Toe Grass + Golden-edged Welwitschia + Ginger Flower + Amaryllis

　　2.3.3 The most distinctive plant configuration in Fuzhou residential areas

　　(1) Royal Coconut - King Coconut - Fan Palm, this is a scene in Yuehui Garden that won the Best Exhibition Award at the 1999 Kunming World Expo, fully reflecting the tropical coconut grove scenery of Fuzhou.

　　(2) The banyan trees are trimmed into various shapes, showcasing the characteristics of Fuzhou, the "Banyan City".

　　2.4 Development trend of plant configuration in residential areas of Fuzhou

　　2.4.1 “People-oriented” thinking

　　The design of the residential area unilaterally emphasizes composition. The paving, plant patterns, architectural sketches, etc. have extremely varied compositions, and are visually beautiful, spectacular, and grand. However, not enough consideration is given to the multi-level and ecological configuration of garden plants.

　　In the creation of plant configuration characteristics in residential areas of Fuzhou, we should not only consider the elements of beauty, but also fully consider the needs of the main body in the residential area - people. We should take the idea of ​​"people-oriented" as the ideological foundation, take people as the foothold, and consider comprehensively from the perspective of people. At the same time, we should achieve harmony between man and nature. The harmonious development of man and nature is a trend in urban development so far, and it is correct now and for a long time in the future.

　　2.4.2 Adhere to the development direction of ecological gardens with "sustainable development"

　　When creating the characteristics of plant configuration in residential areas, it is required to be guided by ecological theory, with the purpose of reproducing nature, improving and maintaining the ecological balance of the community, and with the mission of sustainability with the systematic nature of gardening, the diversity of biological development, and plant landscaping as the theme, so as to achieve systematicity on the plane, hierarchy in space, and correlation in time.

　　2.4..3 Create a healthy plant community that is beneficial to physical and mental health

　　Fully consider the needs of residents to enjoy green space and build artificial ecological plant communities. Health-care plant communities that are beneficial to physical and mental health, such as pine and cypress forests, ginkgo forests, camphor forests, cypress forests, citrus forests, and elm forests; fragrant flower plant communities that are beneficial to eliminating fatigue, such as gardenia bushes, rose bushes, lilac bushes, ginkgo-osmanthus forests, etc.; and plant communities that are beneficial to attracting birds, such as crabapple forests, pyracantha forests, pine and cypress forests, etc., can be arranged on the entire green space at the edge of the community or integrated with the central green space of the residential area. Use the circulation and regeneration functions of the plant community ecosystem to maintain the ecological balance of the community.

　　3. Principles of plant configuration in residential areas of Fuzhou

　　3.1 Adhere to tree planting as the main approach, adapt measures to local conditions, plant trees suitable for the location, combine trees, shrubs, flowers, grasses and vines, pay attention to the diversity of plant species, and improve the ecological content of greening in residential areas.

　　When arranging plants, first of all, the ecological requirements of the plants should be met so that the plants can grow normally. The usual practice is to select "native tree species"; secondly, they should be reasonably arranged, with a reasonable planting density on the plane, and the biological characteristics of the plants should also be considered in the vertical design, paying attention to the reasonable combination of different types of plants such as light-loving and shade-tolerant, fast-growing and slow-growing, deep-rooted and shallow-rooted.

　　3.1.1 Rich plant species (see Appendix 2 for details)

　　This paper believes that the number of plant species in residential areas reaching a certain standard is the basis for ensuring the richness of plant landscape. The following is a comparison of the number of woody plant species in several different residential areas.

　　(1) For green areas with an area of ​​less than 3,000 square meters, no less than 20 types;

　　(2) For green areas between 3,000 and 10,000 square meters, no less than 30 types;

　　(3) For green areas between 10,000 and 20,000 square meters, no less than 40 types;

　　(4) For green areas with an area of ​​more than 20,000 square meters, there must be no less than 50 types of green areas.

　　3.1.2 Reasonable arrangement of trees, shrubs and vines, ground cover plants, bamboos, aquatic plants (see Appendix 3 for details), colorful leaf plants, flowering shrubs, aromatic plants and perennial (perennial) flowers (see Appendix 4 for details)

　　Combine trees, shrubs and vines, evergreen plants and deciduous plants, fast-growing plants and slow-growing plants, and appropriately plant and embellish seasonal flowering flowers and lawns. In the matching of tree species, both biological characteristics and greening landscape effects must be considered, greening and beautification must be combined, the concept of plant landscaping must be established, and a quiet and beautiful living environment must be created.

　　3.1.3 Properly arrange bird-loving plants and nectar plants to attract birds and insects and create a living environment where humans and nature coexist harmoniously (see Appendix 5 for details)

　　The plant configuration in residential areas must be scientific and reasonable, respecting nature. At the same time, it should create a small environment that belongs to residents and in which they can integrate themselves, for a walk and leisure after meals, and create favorable conditions for residents' leisure activities.

　　Some of the bird-loving plants that are currently given priority for promotion in Fuzhou's planning include: camphor tree, kapok, cypress, and fig; the attracted birds include white-crowned sparrow, red-bellied thrush, spotted thrush, green rust-eyed, red-billed blackbill, white-crowned sparrow, yellow-browed sparrow, sparrow, thrush, turtledove, etc.; some of the nectar-producing plants that are given priority for promotion include longan, lychee, loquat, palm, plum blossom, etc., all to better create leisure activity functions in residential areas.

　　3.2 Plant configuration should take into account the function of residential green space

　　There are several types of greening in residential areas: hedge setting, greening beside houses, isolation greening, overhead space greening, platform greening, roof greening, parking lot greening, and road landscape greening.

　　(1) Hedges are mainly composed of densely planted plants in rows, and are divided into shaped hedges and natural hedges. Shaped hedges usually use low-growing shrubs and trees with slow growth, low branching points, and dense branch and leaf structures, which are suitable for manual pruning and shaping. Natural hedges require relatively tall plants.

　　(2) Green spaces near houses are close to residents and are particularly accessible and practical. The orientation of buildings should be taken into consideration when planting green spaces near houses. Tall shrubs should not be planted near windows to avoid affecting daylighting. On the west side of buildings, tall broad-leaved trees should be planted to significantly reduce the temperature in summer and provide warm sunshine in winter. Green spaces near houses should also be designed with an appropriate amount of hard paving that is convenient for residents to walk and stay, and should be planted with trampling-resistant lawns. In addition, shade-tolerant plants should be planted in shaded areas.

　　(3) Trees, shrubs and herbaceous plants should be planted on both sides of residential roads to reduce dust, noise and harmful gases caused by traffic, which is conducive to keeping the interiors of residential buildings along the street quiet and hygienic. Street trees should try to choose trees with horizontally extending branches and crowns to play a role in shading and cooling. Isolation green space should be set up between public buildings and residential buildings, and trees and shrubs should be used to form a dense green barrier to keep the residential area quiet. Garbage stations, boiler rooms, substations, transformer boxes and other unsightly areas in residential areas can be concealed by shrubs or trees.

　　(4) The overhead floor of a residential building is widely used in residential buildings in the southern subtropical climate zone. It is conducive to the ventilation of the residential courtyard and the regulation of the microclimate, convenient for residents to shelter from the sun and rain, and plays a role in the mutual penetration of green landscapes. Shade-tolerant flowers, plants and shrubs should be planted in the overhead floor, and landscapes can be arranged in areas with limited ventilation. The overhead floor is a semi-public space for residents to engage in outdoor activities, and an appropriate amount of activity and leisure facilities can be configured.

　　(5) The greening of the platform should generally be designed in combination with the terrain characteristics and usage requirements. The space below the platform can be used as a parking garage, auxiliary equipment room, shopping mall or activity and fitness venue, etc. The space above the platform can be used as a safe and beautiful pedestrian activity venue. The principle of "people flow in the middle and green space by the window" should be adhered to, that is, the flow of people should be limited to the middle of the platform to prevent interference with the residents on the first floor of the platform; the green space should be set up by the window, and a certain number of shrubs and trees should be planted to reduce the visual interference of outdoor people on indoor residents.

　　(6) Rooftop green space is divided into two types: slope roof greening and flat roof greening. Plants that are drought-resistant, transplant-resistant, strong in vitality, strong in wind resistance, and low in appearance should be planted according to the above ecological conditions. For slope roofs, clinging vines or climbing plants are mostly selected. For flat roofs, flowers and trees with strong ornamental value are mainly planted, and small items such as pools and flower stands are appropriately configured to form peripheral and garden-style greening.

　　In general, when selecting trees, flowers and plants for beautification of residential areas, it is advisable to select refined species rather than complex species. In terms of tree species, trees, shrubs and ground covers should be combined as much as possible according to the purpose of cultivation and growth habits, and the park-style greening characteristics of "grass as the base, trees for shade, and flowers, vines and shrubs for clever embellishment" should be highlighted. If summer shade is required, it is advisable to choose tree species with tall trunks, extended crowns, beautiful leaves and bright and fragrant flowers, such as sycamore, paulownia, Sophora japonica, Koelreuteria paniculata and Catalpa ovata, and to plant flowering shrubs such as Bauhinia, Syringa sylvestris, Crape Myrtles and Hibiscus sylvestris, so that the heights are clearly defined and a barrier of green shade and fragrance is formed.

　　3.3 Landscape Requirements

　　Gardens and green spaces not only have practical functions, but also can form different landscapes, giving people visual, auditory and olfactory beauty.

　　When selecting flowering shrubs for residential areas in Fuzhou, attention should be paid to their natural tree shape and flowering season. For example, the Chinese crabapple has an upright stem and a thin tree shape. In early spring, the tree is covered with pink flowers, like a graceful girl. The weeping crabapple has an umbrella-like shape. When it blooms in spring, a cluster of red flower filaments hang down, full of affection. Summer flowering tree species such as crape myrtle, hibiscus, and pearl bush have a longer flowering period, especially crape myrtle, which can bloom for up to 100 days. The flowering period of weigela is when the spring flowers are withering and there are not many summer flowers. It can be appropriately decorated to make the residential area full of flowers.

　　When beautifying residential areas, attention should also be paid to the selection of climbing plants, such as creepers, trumpet creepers, ivy, wild roses, etc., which can be attached to the wall; wisteria, grapes, honeysuckle, and kiwi can be used as ornamental trellises, and people can rest and enjoy the cool under the trellises. Many herbaceous climbing plants, such as morning glory, sweet peas, and small gourds, climb up bamboo fences or flower walls, adding a lot of natural interest to the beautification of residential areas, which is in line with the people-oriented concept.

　　4. Plant configuration techniques in residential areas of Fuzhou

　　4.1 Use the style of plants

　　(1) Ecological habits

　　Plants have morphological characteristics of trees, shrubs, herbs, and vines, as well as ecological characteristics such as water and humidity tolerance and drought tolerance, preference for shade and sun, alkali tolerance and alkali fear, as well as other resistances (such as wind resistance, resistance to harmful gases, etc.) and differences in pH [14]. If these ecological characteristics of plants are not met, they will not grow or grow poorly, and there will be no style to speak of. For example, weeping willows love water and humidity, have strong adaptability, have drooping and soft branches, tender green leaves, and slender leaves. Planting them by the water will create a charm like "willows swaying, soft branches brushing the water, green and yellow, and birds relying on people."

　　(2) The posture of the plant itself

　　Various plants have different postures, some are relatively regular, such as Photinia and Ailanthus, while others have a dynamic momentum, such as pine, elm, and Albizia Julibrissin. When arranging them, it is important to pay attention to the harmony between plants or between plants and other elements in the environment; at the same time, it is also necessary to consider the changes of plants in different growth stages and seasons, so as not to create an unbalanced situation.

　　For example, Pinus tabulaeformis is a large evergreen tree with dark brown bark, peeling scales, and dark green needle-shaped leaves. Those grown on plains are straight and upright, while those grown on mountains are twisted and varied. Isolated Pinus tabulaeformis has more branches and layers, with a flat crown, forming a majestic, cold-resistant, ancient and strong style. If we add "personification", pine, bamboo and plum are called "Three Friends of Winter", reflecting their cold-resistant, superb and strong style; or "orchid makes people quiet, chrysanthemum makes people wild, lotus makes people calm, peony makes people gorgeous, bamboo makes people elegant, tung makes people clear..." to reflect the morphology and ecological characteristics of different plants, we can produce a "personified" plant configuration landscape style, and thus obtain the artistic effect of garden plant landscape with national essence.

　　4.2 According to different configuration methods

　　4.2.1 Reflect the city’s cultural characteristics in the selection of plant species

　　1. Application of the city flower and tree

　　The symbolic meanings they possess have also risen to become symbols of the region’s civilization and the city’s culture. For example, the city flower of Shanghai is the white magnolia, which symbolizes a pioneering and enterprising spirit[17]; the kapok tree of Guangzhou is known as the hero tree, symbolizing a thriving career and vitality; and the osmanthus of Hangzhou, the magnolia of Yangzhou, the camellia of Kunming, and the erythrina of Quanzhou are all plants with a long cultivation history and profound cultural connotations.

　　Therefore, Fuzhou City uses the symbolic meaning of the city flower and city tree and configures them in a complementary manner with other plants, sketches, and structures, which can give them a strong cultural atmosphere, not only playing a positive educational role for children, but also meeting the spiritual and cultural needs of citizens.

　　2. Application of native plants

　　Native plants are the most adaptable to local natural growth conditions. They not only meet the requirements of suitable trees for suitable places, but also represent a certain vegetation culture and regional customs. For example, coconut trees are the representative of typical southern scenery, while poplar trees in northern cities always silently represent its fearless spirit. In southern cities such as Guangzhou, Zhuhai, Shenzhen, Huizhou, and Fuzhou, their unique natural conditions have given the city a distinctive plant landscape, such as various large-flowered trees, palm plants, colorful leaf plants, climbing plants, perennial flowers and ground covers, etc. These well-growing and rich plants provide favorable conditions for the city's diversified plant configuration. From the plant landscape of a city, we can not only see the character and identity of a place, but also the characteristics of a local era culture, or regional cultural characteristics. One of the characteristics of urban culture is regionality, and native plants are one of the cultural elements that can reflect local regional characteristics.

　　3. Protection of ancient and famous trees

　　Because ancient trees are witnesses of history and living cultural relics; famous trees are precious resources. They are all historical heritages with high cultural value and can add great wealth to the city's culture.

　　In addition, the application of plants with obvious scientific and technological value and popular science significance in cities can reflect the level of popular science and civilization of a city, and indirectly reflect the level of civilization of a city. The banyan tree can form a forest of one tree, the insectivorous reason and insect catching mechanism of pitcher plants, the symbiotic relationship between figs and fig wasps, and the ginkgo nut is not a fruit, etc., all express a natural phenomenon. These plants provide vivid cognitive objects for the popularization of scientific knowledge and play a good educational function.

　　4.2.2 Creating distinctive residential areas through various methods

　　When greening residential areas, plant configuration should also be based on the theory of ecological gardening, simulate the natural ecological environment, use plant physiology, ecological indicators and garden aesthetics principles to configure plants, create a complex structure, and maintain the stability and durability of plant communities in space and time.

　　(1) Tree species matching

　　Combine trees, shrubs and vines, evergreen plants and deciduous plants, fast-growing plants and slow-growing plants, and appropriately plant and embellish seasonal flowering flowers and lawns. In the matching of tree species, both biological characteristics and greening landscape effects must be considered, greening and beautification must be combined, the concept of plant landscaping must be established, and a quiet and beautiful living environment must be created.

　　(2) Strive to vary tree species on a unified basis

　　Create a beautiful canopy line to break the monotony and dullness of the building complex. Focus on selecting plants of different tree shapes, such as tower, column, sphere, weeping branches, such as cedar, metasequoia, cypress, camphor, magnolia, ginkgo, locust, weeping peach, etc., to form a canopy line with strong changes; plants of different heights form a canopy line with moderate changes; use the changes in terrain height to arrange different plants to obtain corresponding changes in the canopy line. By planting flowering shrubs near the edge and using short and dense Malus malus, Pittosporum tobira, azalea, Hypericum, etc. to form a naturally changing curve.

　　(3) Plant arrangement should be clear in layers, with a prominent background and attention paid to color blocks and seasonal changes

　　When arranging plants in residential areas, attention should also be paid to the matching of levels and background. It is advisable to arrange them in multiple levels with trees, shrubs, flowers, and ground cover plants. Plants with different colors and flowering periods are arranged in layers to make the plant landscape rich and colorful. Background trees should generally be taller than foreground trees, and the planting density should be large. It is best to form a green barrier, with dark tones, or a large difference in tone and chroma with the foreground to enhance the foil effect. In this way, the space is divided and connected, and through various levels, the space has a more natural rhythm. Xuehen mentioned in "The Arrangement of Garden Plants" that "there is no beauty without quantity" in garden design, and the beauty of plants sometimes needs to be reflected through groups.

　　The technique of color block design is to use a large number of plants planted together to reflect a group of beauty, making it the focus of sight. Reasonable use of color blocks can attract people's attention to the greatest extent, and it is also a form of expression that modern people are more likely to accept.

　　Residential areas are the living and resting environment for residents all year round. Plant configuration should have seasonal changes to keep pace with the residents' life patterns of spring, summer, autumn and winter. For example, spring landscapes composed of jasmine, peach blossoms, and lilacs; summer landscapes composed of crape myrtles, albizzia, and pomegranates; autumn landscapes composed of osmanthus, red maple, and ginkgo; and winter landscapes composed of wintersweets, honeysuckle, and nandina domestica.

　　(5) Configuration method

　　In terms of configuration, a combination of regular and natural plant configuration techniques can be adopted. There are several ways to configure plants, such as solitary planting, paired planting, row planting, clump planting and group planting. Among them, solitary planting mainly shows the individual beauty of trees and is often used as the main scenery of the garden space; paired planting is to plant approximately equal numbers of trees symmetrically, and is often used on both sides of garden gates, building entrances, squares or bridgeheads; row planting is to plant trees in rows and strips, and is often used on both sides of streets and roads, or around regular squares; clump planting is a combination of three or more different tree species, which is a commonly used method in gardens and can be used as the main scenery or supporting scenery, or as a background or isolation measure; group planting is a group combination of the same tree species, with a large number of trees, mainly to show the beauty of the group, with the interest of "forest".

　　Generally, one to two rows of roadside trees are planted on both sides of the roads in the area, and some shade-tolerant flowering shrubs can be arranged in a regular pattern, and the exposed ground can be covered with lawns or ground cover plants. Other green spaces can adopt natural plant arrangement techniques to form a patchwork and seasonal plant landscape.

　　5. Conclusion

　　A beautiful garden and greening environment has become the most basic element of a residential community and is directly related to the overall level and quality of the community. Different communities have unique styles in plant configuration, reflecting the diversity of plant species in nature. Tree species should be rich but not disorderly. Good planting design can become a clear landmark of the community. With the growing call for building ecological and green houses[22], many real estate developers have begun to carry out gardening while building residential communities, trying to create a beautiful living environment for residents. The garden plant configuration of residential communities should highlight local characteristics and have a distinct personality, so as to achieve the best ecological, social and economic benefits.