| Soil test value (0.1 M H2SO4-P, mg·kg−1) | kg P2O5 ha−1 to apply (to raise soil P to 80 mg·kg−1) |
| 30 | 600 |
| 35 | 525 |
| 40 | 475 |
| 45 | 425 |
| 50 | 375 |
| 55 | 325 |
| 60 | 275 |
| 65 | 200 |
| 70 | 125 |
| 75 | 50 |
| 80 | 0 |