PURPOSE: To eliminate the setting of measuring machine at a greening site, provide a good working efficiency, and maintain accuracy by charging a mixture of organic soil improvement material, plant seed tertilizer, and erosion preventing material in a soluble plastic bag.

CONSTITUTION: When one batch of greening base material is dissolved in a fixed amount of water, organic soil-improvement material, fertilizer, high polymer system erosion preventing material, and a specified amount of seed 5 are filled into a greening seed storing bag 1, and the bag is charged into water. In this case, seed is filled into a soluble plastic bag 1, a combination of several types of required amount of seed suitable for greening site is charged into water, and the bag 1 is dissolved. Thus a specified amount of base material for blowing can be obtained.