The invention discloses a cold region rice 
seedling growing multi-potential medium. The medium comprises 40-60 parts of expanded rice 
husk, 30-40 parts of fermented 
mushroom dreg, 10-30 parts of fermented 
straw and 5-10 parts of 
vermiculite. A preparation method of the medium comprises the following steps: 1, carrying out 
extrusion expanding treatment on rice 
husk; 2, fully mixing the expanded rice 
husk obtained in step 1 with a 
fertilizer and a bactericide, and standing; 3, respectively carrying out aerobic 
fermentation on 
mushroom dreg and 
straw; 4, adding 
sulfuric acid to a product obtained in step 3 to adjust the pH value; 5, mixing a product obtained in step 2 with a product obtained in step 4, adding 
vermiculite to the obtained mixture, using a 
sulfuric acid solution to adjust the pH value, and stirring to fully mix the material; and 6, sieving a product obtained in step 5, packaging, and discharging the packaged medium from a factory. All components in the multi-potential medium cooperate with nutrients, growth environment and 
disease prevention factors to organically form a homogenous, multi-potential, safe, efficient and simply operated 
seedling growing carrier, so various problems appearing in routine 
seedling growing using soil dressing + a seedling strengthening agent are thoroughly solved, and the rice output is improved.