How to do the test
1. Dig out a section of soil under plants with your spade (approx 20cm depth or deeper if necessary).
2. With a ruler / measuring tape, record the depth at which you estimate that 80% of plant roots are concentrated in the soil, and record this number (in cm) in Sectormentor. There may be a few ‘outlier’ deeper roots, but you can discount them if more than 80% of roots stopped growing at a shallower depth.
3. You can also record the your total root depth in the separate Sectormentor test called ‘Rooting depth total (cm)’ for your reference.