Fertilizers are named according to the 3 macro-elements they contain. If you understand the ratio and the elements, you’ll always know exactly what is contained in each fertilizer bag!
Fertilizer are represented as follows:
Ie. 2:3:2 (22) is 2 parts N, 3 parts P, 2 parts K
7:1:3 (21) is 7 parts N, 1 part P, 3 parts K
The percentage (in brackets) ie. 22 or 21 in the above examples indicates the total percent of the combined elements in the fertilizer bag
SR indicates that the formulation is Slow Release
This means that nitrogen is released slowly into the soil over a period of weeks.
SR* indicates that the formulation is Sustained Release.
Release their nutrients (NPK) at a specific rate over a specific period of time.
Did you know?
Phosphorous is immobile in the soil. This means it does not leach readily through the soil as do Nitrogen and Potassium. As such, it is vitally important that phosphorous is added to all new plantings as it is then incorporated directly at the root zone where it is needed. Ensure Superphosphates, Bonemeal or 2:3:2 are incorporated with each new planting.
Traditional fertilizers contain a blend of the three macro-elements. More advanced formulations may include micro-elements or have other additives that improve and enhance plant growth.