Turfgrass plays a vital role in beautifying the environment, purifying the air, conserving soil and water, and providing recreation sites for people. However, turfgrass growth is limited by environmental factors and management conditions. It is well known that beneficial microbial agents can improve soil structure and nutrient status and enhance the activity of soil enzymes, thereby promoting plant growth. Three types of microbial communities, actinomycetes, Bacillus subtilis, and Bacillus thuringiensis, play a role in promoting plant growth. Municipal solid waste (MSW) compost consists of a rich variety of rapid succession microbial communities, the type and population size of which depend on the composition and content of organic matter in the compost and the interaction among the microorganisms. Microorganisms can be extracted from MSW compost and have a potentially broad application. In the present study, the aforementioned three types of microbial communities were extracted from compost, identified through morphological characteristics and staining, and then applied to a turfgrass medium. The effects of microbial agents on the growth of the turfgrass (Festuca arundinacea) and soil enzyme activity were investigated. The results indicated that each type of microbial agent significantly increased the plant height, biomass, and chlorophyll content of F. arundinacea compared to the controls. On day 30 of the investigation, plant heights were 21.9%, 18.7%, and 29.1% higher in actinomycetes-, B. subtilis-, and B. thuringiensis-inoculated plants than their controls, respectively. The aboveground fresh and dry weights of F. arundinacea inoculated with B. subtilis increased by 57.0% and 40.9%, respectively, compared to the control. A significant enhancement of 60.0% in belowground dry weight was observed in plants inoculated with B. thuringiensis. The total chlorophyll contents of F. arundinacea inoculated with actinomycetes and B. subtilis increased by 52.3% and 36.6%, respectively, compared to their controls. Furthermore, application of microbial agents markedly stimulated the activities of soil enzymes. In soils inoculated with actinomycetes, B. subtilis, and B. thuringiensis, the urease activity increased by 8.38-, 2.77-, and 2.45-fold, respectively; the polyphenol oxidase activity increased by 20.6-, 7.7-, and 8.4-fold, respectively; and the peroxidase activity increased by 3.3-, 4.6-, and 4.3-fold, respectively, compared with their controls. On the basis of the results obtained, we conclude that the three types of microbial communities derived from the compost can effectively increase soil enzyme activities, improve the micro-ecosystem of the plant rhizosphere, and improve soil fertility and nutrient utilization, thereby promoting turfgrass growth and improving turf quality. This study can provide a basis for the utilization of microbial agents in turf establishment.