You can't. Generally, rapeseed cake is toxic. It is suggested that leavening agent should be applied after fermentation, which can not only improve the nutritional content of organic matter, but also reduce the decay time of rapeseed cake directly applied. Flowers generally require higher culture medium. Therefore, it is suggested to use special Gymboree flower culture medium starter to ferment the culture soil. Or apply special rapeseed cake starter, and the application effect will be better after fermentation. Baidu Gymboree will do.