Chinese kale (Brassica oleracea var. albloglabra) was cultivated in the screenhouse of the Faculty of Agriculture, Chiang Mai University Thailand. Randomized complete Block design (RCBD) was used in this experiment. Selected seedling media (SSM, coconut husk compost) without leonardite and microbial addition was used as control treament. The media was mixed with lonardite (้humic acid = 57.96%) in various percentages: 5, 10 and 15% (w/w). The mixed media (SSM -leonardite)were used to raise the seedling with and without beneficial microorganisms (16 treatment, 3 replications) (Table 1). In the treatment with beneficail microoganisms, three isolates -Azospirillum sp. (VAs 2), Beijerinckia sp. (VBe 75) and actinomycetes (VAc 77) selected from the previous study (Shutsrirung, 2010) -were inoculated as a single isolate to Chinese kale seedlings (107 CFU plant-1) after one week of germination. Growth parameters; shoot and root dry weight: and nutrient content were measured at 20 DAI