Plant Selection of Roof Gardens in Sichuan

① Choose shrubs and herbs with strong drought and cold resistance. Because of the high temperature and strong wind in summer and poor water retention and heat preservation in winter, plants with strong drought resistance and cold resistance should be selected in roof gardens. At the same time, considering the special geographical environment and load-bearing requirements of the roof, attention should be paid to selecting more shrubs and herbs to facilitate the transportation, planting and management of plants.

② Select positive and barren-tolerant shallow-rooted plants. Most parts of the roof garden are in direct sunlight, and the light intensity is high, so the plants should be positive as far as possible. However, in some specific small environments, such as under the flower stand or near the wall, the sunshine time is short, so some semi-positive plant species can be selected appropriately to enrich the plant species in the roof garden, and the roof planting layer is thin. In order to prevent the root system from eroding the roof structure, plants with shallow roots should be selected as far as possible. Because fertilization will affect the sanitation of the surrounding environment, the roof garden should try to plant barren-tolerant plant species.

③ Choose plant varieties that are resistant to wind, lodging and waterlogging. Generally, the wind over the roof is stronger than the ground, especially in rainy season or typhoon, and wind and rain are the most harmful to the survival of plants. In addition, the roof planting layer is thin and the soil water storage performance is poor. Once it rains heavily, it is easy to cause short-term water accumulation. So try to choose some plants that are resistant to wind, lodging and short-term water accumulation.

④ Choose plants that are mainly evergreen and can overwinter in the open field in winter. The purpose of building a roof garden is to increase the green area of the city and beautify the "fifth facade". As far as possible, the plants in the roof garden should be evergreen plants, and the varieties with beautiful leaves and plants should be selected. In order to make the roof garden more colorful and reflect the seasonal changes of the garden, some colorful tree species can be planted appropriately. In addition, if conditions permit, some potted seasonal flowers can be arranged to make the garden have flowers in all seasons.

⑤ Try to choose native plants and introduce new varieties of greening. Native plants have strong adaptability to the local climate. In the roof garden with relatively harsh environment, choosing native plants can get twice the result with half the effort. At the same time, considering that the area of the roof garden is generally small, in order to decorate it more exquisitely, some new varieties with high ornamental value can be selected to improve the grade of the roof garden. 1. Garden roof greening can be made into a small garden to serve tourists, which is mostly used in service buildings such as hotels and restaurants, and can provide recreation space for guests. Small gardens should have appropriate undulating landforms, with small pavilions, flower stands and other garden architectural sketches, and dotted with rocks. Choose small trees with shallow roots to match with shrubs, flowers, lawns, vines, etc. In order to meet the needs of plant root growth, the thickness of planting soil should be 30 cm to 40 cm, and the local design can be 60 cm to 80 cm. This kind of roof garden should pay special attention to the overall consideration in architectural design, in order to meet the requirements of roof garden for roof bearing capacity, and try to make the heavier parts (such as pavilions, flower racks, rocks, etc.). ) is designed on the beam and column.

2. The patterns of color blocks are composed of foliage plants such as Buxus buxus, Berberis purpurea and Ligustrum lucidum, or neat and gorgeous grass flowers and lawns, which have a good overlooking effect and are mostly used for low-rise roof greening when roofs are staggered. Because we pay attention to the overall visual effect, there is no garden road inside, only the management channel is left.

3. The seasonal arrangement adopts potted flowers, which can be changed at any time according to their full flowering period, and chlorophytum can be placed on the edge of the building, taking into account the greening of the wall. This method is mostly used for low-rise roof greening.

Third, the structural layer of the landscaping layer is generally divided into insulation layer, waterproof layer, drainage layer, filtration layer, soil layer, plant layer and so on.

1. insulation layer: polystyrene foam board can be used, and leveling should be paid attention to when laying.

2. Roof greening must not leak after adding waterproof layer. Once there is a problem, the users of the house will have rejection psychology, which will directly affect the promotion of roof greening. It is best to design it as a composite waterproof layer.

3. The drainage layer is located on the waterproof layer, which can be combined with the rainwater pipe on the roof to discharge excess water to reduce the burden of the waterproof layer. The drainage layer mostly uses materials such as gravel and ceramsite.

4. Planting layer Planting layer generally adopts soilless substrate, which is made of vermiculite, perlite, peat, humus, peat soil and sand.