Organic, All-Natural & Non-GMO Sourced Asparagus Fertilizer (4-3-1)! The Urban Farmer Asparagus Fertilizer will increase asparagus yields, size, health and taste. This 4-3-1 (NPK) fertilizer ratio is specially formulated to get the most out of your asparagus. This fertilizer gives the asparagus exactly what it needs at the right time