The concepts and principles of low-carbon design for urban garden landscapes were explored, and strategies for enhancing landscape carbon sinks were proposed. In terms of low-carbon landscape design, it mainly unfolds from three aspects: life cycle, ecological approaches, and application in garden plant landscape design. Among them, the low-carbon design concept based on the life cycle requires the comprehensive implementation of low-carbon principles throughout the entire cycle of landscape design and construction, striving to achieve low-carbon goals in all stages of the project. Low-carbon garden planning and construction under the ecological approach focuses on achieving low-carbon goals by utilizing the functions of natural ecosystems, including strategies such as expanding the scale of urban green spaces and optimizing the layout of green spaces. The application principles of the low-carbon concept in the design of garden plant landscapes include creating scenes by utilizing existing terrain and configuring native plants, etc. The infiltration methods include selecting appropriate plant species, optimizing plant configuration methods, and improving maintenance levels, etc. In terms of carbon sink enhancement strategies, by increasing the green volume of the city, rationally planning the landscape layout, choosing appropriate carbon-sequestration plants and optimizing the plant configuration, the ecological and economic benefits of the garden landscape have been effectively enhanced. This article provides a reference for the sustainable development of cities and the improvement of carbon sinks in garden landscapes.