As a raw material of high-quality organic fertilizer, the resource utilization of food waste biogas residue is of great significance to improve urban waste removal and ensure the health of the urban ecological environment. In this paper, three commonly used garden landscape plants, Michelia alba, Lagerstroemia indica and Cosmos sulphureus, were selected to carry out potted plant experiments for the application of aerobic fermentation compost (referred to as biogas residue compost) for wet waste slag and also it to study the effect of different amounts of biogas residue composting on the main physical and chemical properties of soil and plant growth indicators. The results showed that after mixing the compost of biogas residue in the soil, the soil nutrient and soil acidity and alkalinity improved significantly, except for the conductivity value. The amount of biogas residue composting reached 30% has an apparent inhibitory effect on the growth of three kinds of plants, with different degrees of coke leaves, death, and other toxic effects. When the amount of biogas residue composting is less than 20%, it has an excellent pro-life impact on plants, when the amount of biogas residue composting is 20%, white magnolia and sulfur grass are the best, and when the amount of biogas residue composting is 10%, the purple is the best. The research provides data support for the scientific application and popularization of biogas residue compost in landscaping conservation.