Objective  In order to better responding the requirements of green development in the era of ecological civilization and demonstrate new green construction methods, it is necessary to sort out the design system for the green construction of Expo gardens, which will play a leading and referential role in realizing efficient resource utilization, minimizing waste discharge, and significantly improving environmental quality in urban and rural construction.

Methods  This research reviews the whole-process records of the design and construction project (hereinafter referred to as the project) of the 13th China (Xuzhou) International Garden Expo (hereinafter referred to as the "13th China Garden Expo"), based on which figures out the characteristics of the technical design system for the 13th China Garden Expo by means of green construction following the goal of quarry pit garden revival.

Results  1) In the process of design, the project, in view of the serious problem of soil and water loss on site, improves local soil structure through soil and plant restoration, combs existing topography and water system ditches in combination with local realities, and establishes a variety of landscape soil and water conservation facilities such as dry stream, ecological pond, sand sink, ecological river channel, ecological grass ditch and stone shed ditch. In addition, the project builds a resilient sponge garden that can prevent people from wetting their shoes on rainy days inside the garden. 2) For existing quarry pit occupying a large area, the project, from the four dimensions of slope management, micro-topography adjustment, soil matrix improvement, and construction of self-stable complex plant community, improves challenging site conditions, reshapes the nutrient matrix layer, achieves rapid and stable recovery of vegetation communities, and builds a safe and stable ecosystem through technical design. 3) For the woodland area, the project adopts the replanting method of "small plant community, massive mixed plantation" to achieve forest transformation by replanting the original plant Platycladus orientalis, and adding deciduous broad-leaved tree communities in local area and multi-level broad-leaved mixed forests outside the forest edge. The evolution from pure forest to mixed forest endows the forest ecological environment with more stable structure, and makes it organically interact with surrounding gardens, thus achieving the integration of ornamental scenery and ecological efficiency. 4) As to material selection, the project adopts a large number of local plants and site materials with low maintenance and management costs, as well as relevant construction and earthwork wastes recycled. Meanwhile, industrial waste parts and daily necessities are also used to create art installations, to convey the concept of environmental protection, to realize energy conservation and innovation, and to achieve the goal of returning nature to nature. 5) The 13th China Garden Expo also demonstrates the prefabricated garden landscape for the first time, marking the initial application of a new garden construction mode that is low-carbon, economical and sustainable. This mode can achieve the integration of modular combinations and prefabricated landscape, and accordingly create multi-functional and mobile experience spaces.

Conclusion  The 13th China Garden Expo integrates the concept of "new process, new technology, new equipment and new material" into the whole process from planning and design to material selection, construction management, and operation and maintenance, and always practices the green construction mode featuring resource conservation and environmental protection throughout its life cycle.