Example sources of nutrients
Below are some examples of commonly available fertilisers and the proportions of each nutrient they contain.
| Fertiliser | N content |
P* content |
K* content |
Mg content |
Ca content |
S content |
|---|---|---|---|---|---|---|
| Ammonium nitrate | 33-35% | |||||
| Ammonium sulphate | 20-21% | 24% | ||||
| Bone meal | 3% | 9% | ||||
| Dried blood | 12-14% | |||||
| Hoof and horn | 12-14% | |||||
| Kieserite | 15% | 21% | ||||
| Potassium nitrate | 14% | 38% | ||||
| Superphosphate | 8-9% | 20% | 12-14% | |||
| Urea | 46% |
* In some cases, fertilisers containing phosphorous (P) express their % in terms of phosphoric acid, while those containing potassium (K) express their % in terms of potash, instead of the base element. Here we have shown the % of the base element.
Nutrients can also be sourced by using the following, bulkier, supplements. However, the nutrient content of each one is highly variable.
- Farmyard manure
- Slurry or urine
- Garden, mushroom, or leaf composts
- Seaweed
- Wood ash
- Sawdust, bark and wood waste
