Soil Crop Monitor
I just applied fertiliser, can I perform a Soil Crop Monitor?
For foliar feeding, this is not a problem. The plant material is washed before analysis, so only nutrients taken up by the plant are measured. If you have applied a fertiliser to the soil, we suggest waiting at least 2 weeks. In the soil analysis, all plant available nutrients are measured. This means that the nutrients from the fertiliser are also accounted for. If the fertiliser has not been completely dissolved, it is possible that high nutrient values will be found.
Why do you advise to sample less than 1 ha for Soil Crop Monitor?
When samples are taken on a larger area, the heterogeneity of the field can influence the results, and make them less reliable. By sampling a small area, this problem is much smaller. It is best to sample on a representative location, which is secured by GPS. The next sample can then be taken at the exact same location. Another option is to perform a Soil Crop Monitor in higher and lower performance areas of the field. The results can then give insight into the reason behind the differences.
I applied plenty of nitrogen (N) fertiliser, but I don’t see high mineral N values in the soil on my report. How is that possible?
It is possible that the crop has taken up the nitrogen (N) very efficiently. You can check this by looking at the N uptake by the crop, which is also shown on the report. If this is not the case, the N can be leached. If there has been a very wet period, the N can also be volatilized. Another possibility is that the N has been immobilized (taken up) by the soil life. It will then become available at a laterstage.
Why are my mineral N values so high?
Sometimes mineral N values in the soil can be higher than expected during the season. In a long period without precipitation, plants have difficulty taking up nutrients from the soil because there is not enough moisture in the soil. However, there can be enough moisture in the soil to sustain mineralisation by the soil life. Another possibility is recent fertilisation, or rain after a long period of drought (then mineralisation will increase).
Why is it important to know the emergence date?
After the emergence date, the crop will grow and take up nutrients. By combining the sampling date with the emergence date and linking this with the total nutrient need of the crop, the advice is calculated.
Why is it important to report the expected yield?
For the advice, we assume a standard yield for the crop. However, if you know your yield will deviate from that (higher or lower), we can adjust the advice. This will result in an optimal fertilisation for your crop.