NOVELTY - Improving overwintering ability of turf by using urban household waste composting offscouring, comprises (i) sieving compost and drying, providing compost, adding water, filtering, collecting filter solution, mixing washing solution of compost, placing in a refrigerator, and placing slag into a baking oven, (ii) taking seed of the ryegrass, sowing into the culture dish with processed compost slag, germinating, watering, and culturing, (iii) culturing seedling, placing in lighting incubator, decreasing temperature, and (iv) cutting the plant, transplanting into the field, and observing growth.    USE - The method is useful for improving overwintering ability of turf by using urban household waste composting offscouring.    ADVANTAGE - The seedling of the ryegrass cultured by the compost is processed in cold environment without any difference in the protective enzyme, proline content, conductivity, and other index of the seedling of the control group, where the above ground biomass of the seedling is 26.74, and for the filter paper substrate group having relatively poor matrix nutrition, the above ground biomass of the seedling after the cold processing is reduced to 23.21. The turf obtained by the method can completely survive during the winter environment with a temperature not less than 10 degrees C, and achieves targets of storage and annual production in winter.    DETAILED DESCRIPTION - Improving overwintering ability of turf by using urban household waste composting offscouring, comprises (i) sieving the compost and drying, providing the compost after sieving and drying, placing into the water and filtering, collecting the filter solution, adding water for twice and filtering the compost continuously, collecting the filter solution of each time, mixing the washing solution of the compost for 3 times, placing in a refrigerator for storage, placing the slag after filtering into a baking oven at 105 degrees C until the weight is constant, where the volume ratio between the compost and the water is 1:1-2, (ii) taking full and uniform seed of the ryegrass, sowing into the culture dish with the filter paper and the processed compost slag, where each culture dish comprise compost slag (1 g), placing the culture dish with the seed in the lab for germinating, watering once or twice in every morning and evening, changing the location of each culture dish to assure the same lighting, where the average temperature in the lab during the culturing period is maintained at 16.8-22.1 degrees C, and the average humidity is maintained at 42.5%, (iii) starting from the tenth day after the seed germinates, watering compost washing solution (5-8 ml) to the culture dish for culturing the seedling of the ryegrass, then after 40 days of seed germination, moving it to the lighting incubator, setting the initial temperature at 12 degrees C, decreasing the temperature gradually each day, where the temperatures are respectively 12 degrees C, 10 degrees C, 8 degrees C, 6 degrees C, 4 degrees C, and 2 degrees C, and (iv) cutting the plant after the cold processing, placing in a carton box and storing at an average temperature of -4 to -10 degrees C, transplanting into the field when the plant starts to turn green in spring, and observing the growing condition.