| NPK nutrient load | SW0 | SW33 | SW66 | SW100 |
| Control | 1.622 | 2.333 | 2.543 | 2.509 |
| 2 g | 2.517 | 2.309 | 1.694 | 1.936 |
| 5 g | 2.728 | 2.455 | 1.533 | 1.385 |
| 10 g | 2.253 | 2.182 | 1.518 | 1.002 |