To provide a slow-acting potassium fertilizer, especially a slow-acting potassium fertilizer which can develop fertilization effect early during a long spell of rain in early spring (stalk rising stage of wheat) after basal fertilization and subsequent wheat seeding. 緩効性のカリウム肥料であって、特に、元肥を施用し小麦を播種した後、なたね梅雨期(ムギ茎立ち期)初期に肥効が発現する緩効性のカリウム肥料を提供する。 - 特許庁