If you want to mix your own general-purpose organic fertilizer, try combining individual amendments in the amounts shown here. Just pick one ingredient from each of the three groups below. Because these amendments may vary in the amount of nutrients they contain, this method won’t give you a mixture with a precise NPK ratio. The ratio will be approximately between 1-2-1 and 4-6-3, with additional insoluble phosphorus and potash. The blend will provide a balanced supply of nutrients that will be steadily available to plants and encourage soil microorganisms to thrive.
2 parts blood meal
3 parts fish meal
3 parts bonemeal
6 parts rock phosphate or colloidal phosphate
1 part kelp meal
6 parts greensand
For more information on using orgainc fertilizers and undertanding the difference between chemical and organic fertilizers, see our Fertilizer page.