N-Min and N-Calc - Unique Service
"The GrowHow N-Min & N-Calc service is a practical way to optimise Nitrogen inputs and take the guesswork out of calculations."
Ross Leadbeater
GrowHow Adviser
Calculating the optimum fertiliser recommendation is not easy. It depends on many factors - soil type, soil organic matter, winter rainfall, soil temperature, previous cropping, current crop, yield & quality expectations, the amount of Nitrogen already taken up by the crop and more.
GrowHow's unique N-Min & N-Calc service takes the guesswork out of fertiliser calculations.
N-Min is the only Nitrogen test that measures both Soil Mineral Nitrogen and the Additional Available Nitrogen to give a Total Nitrogen measurement of what will be available to the crop during the growing season.
This is how it works.
1. Soil samples are taken down to 30cm* in early spring and sent to the laboratory:
- The samples are analysed for mineral Nitrogen content and incubated to establish how much Additional Available Nitrogen is going to be available to the growing crop.
2. Based on the 0-30cm sample the laboratory estimates the amount of Nitrogen that will be supplied from the 30-60cm profile:
- This estimate comes from a calibration model based on 200 deep core soil samples taken annually in early January and analysed before the commercial N-Min season starts. This is by far the most comprehensive Nitrogen database in the UK.
3. The total Additional Nitrogen figure is adjusted to account for Nitrogen supplied from the 60-90cm soil depth.
These three elements are combined to produce a measure of the Total Nitrogen Reservoir.
(* or 60cm if organic manures have been applied in the last 24 months.)
N-Calc
uses the N-Min result to assess Soil Nitrogen Supply (SNS) more accurately. With the farmer's yield & quality expectations it will calculate the optimum Nitrogen fertiliser rate for cereals and OSR.
SNS = Crop N + Soil N
N-Calc has been developed from GrowHow's own and independent research work. Recently ADAS was commissioned to review, update and improve N-Calc by incorporating all the latest research. It is an ongoing process.
GrowHow N-Calc recommendations will:
- Ensure farmers' yield & quality aspirations are met
- Allow changes in economic circumstances to be accounted for
- Minimise the environmental impact of crop production
- Ensure that every £ spent on Nitrogen is well spent
"Takes the guess work out of fertiliser calculations." - Michael Taylor
Click here to view the video
For details of local service providers email: advice@growhow.co.uk or telephone the GrowHow Advice Centre: 0151 357 5758.
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