A lower price per bag does not necessarily mean a lower cost per hectare. A humic product can require a different application route, number of passes or handling time. The useful purchasing question is therefore: what changes in the farm’s income after the complete programme has been paid for?
This guide separates a measured crop response from an economic decision. It gives an original worked example, not a MetraHum performance claim, product quotation or application-rate recommendation. All example prices and responses are hypothetical; replace them with your own invoices, local sale terms and trial results.
KEY TAKEAWAYS
- Compare complete programmes on the same area and harvest basis.
- Calculate the minimum extra marketable yield before buying at scale.
- Keep a no-response scenario and do not book unmeasured savings.
Define exactly what is being compared
Write down the crop, field, season, baseline fertilisation and candidate programme. For an add-on test, hold the underlying management constant. A simultaneous change in nitrogen, irrigation and humic input evaluates a package; it cannot isolate the value of the humic product. Utah State University’s on-farm guide explains this control principle.
For each candidate, request the current label, batch identity and a quote for the planned area. Compare SOIL-G, WSG Core and K18 through their relevant product pages and intended routes, not by assuming equal kilograms, litres or nutrient value. Product suitability and the locally applicable label come before the cost calculation.
Build a complete incremental cost
Iowa State’s partial-budget framework compares added revenue and reduced costs against added costs and lost revenue. Only changes belong in this comparison. For a humic programme, our practical worksheet starts with product delivered to the farm, then adds preparation labour, application, cleaning and any additional testing needed for the commercial programme.
If the product travels in an already scheduled pass, charge the actual extra work rather than a second full pass. If it requires a separate trip, include that trip. Keep one-off research expenses separate from recurring commercial costs, but show both totals so a trial budget is not mistaken for a repeat-purchase budget.
Use saleable harvest, not appearance
Nebraska’s on-farm research protocols use repeated, randomised comparisons. For the economic record, harvest a known area, keep treatment identities and compare quantities on the same moisture and quality basis. A greener strip or one attractive plant does not provide a saleable-yield figure.
Value each marketable grade at the price it would actually receive. Record extra sorting, harvesting, drying, packaging and transport where they change with output. Do not claim both a higher average sale price and the same quality premium again as separate income. Similarly, fertiliser or water savings require an explicit comparison and measured quantities.
Calculate break-even yield
For a simple case with an unchanged sale price and no other savings: net change = extra saleable yield × (sale price − extra cost per kilogram) − programme cost per hectare. Therefore, break-even extra yield = programme cost ÷ (sale price − extra cost per kilogram). The denominator must be positive.
Hypothetical example: a programme costs €90/ha, sale price is €0.20/kg and extra harvesting and handling cost €0.02/kg. Break-even is 90 ÷ 0.18 = 500 kg/ha. This is the required response for these assumptions, not a predicted response. With unchanged yield and no other benefit, the loss is the full €90/ha.
| Extra saleable yield | Net change |
|---|---|
| 0 kg/ha | −€90/ha |
| 250 kg/ha | −€45/ha |
| 500 kg/ha | €0/ha |
| 750 kg/ha | +€45/ha |
Stress-test the purchasing decision
In the same example, if sale price falls to €0.16/kg while all costs stay unchanged, the break-even gain rises to about 643 kg/ha. A 750 kg/ha response then leaves €15/ha, rather than €45/ha. Keep this sensitivity beside the central case. ARVALIS’s wheat evaluations also illustrate why economic thresholds depend on both input cost and crop price.
A positive average is not a guarantee for every field. Review variation between replicates, seasons and sites with the agronomist; do not select only the best strip. If plausible responses cross the break-even threshold, keep the commercial area limited while gathering more evidence. Price uncertainty and uncertainty in the crop response are separate risks.
Turn the calculation into a purchase record
Keep one dated sheet containing the product and lot, approved route, area, delivered price, each changed cost, measured marketable yield, actual sale basis, central and downside results, and the decision. A favourable result supports only the programme and conditions tested. Do not transfer it automatically to a different crop, formulation or application route.
Use the linked SOIL-G, WSG Core and K18 pages to discuss product form and application infrastructure with MetraHum. Bring your soil and water results, planned area and existing programme so the technical discussion and commercial quote describe the same job.
PRACTICAL ANSWERS
Frequently asked questions
Does a higher yield automatically mean a profit?
No. Additional marketable revenue must exceed the programme cost and the extra costs associated with that output. Check grade, moisture and actual sale terms before assigning value.
Can I count a fertiliser saving in advance?
Only as an explicitly labelled scenario. A verified saving needs a separate comparison showing the actual input reduction and its effects on saleable yield and quality. Do not assume that adding humic material permits a fertiliser reduction.
Are the example prices MetraHum prices?
No. They are invented solely to explain the calculation. Use a current quote and your own crop-sale assumptions; the example does not predict a product response.
Technical references
- Iowa State University — Partial Budgeting: A Tool to Analyze Farm Business Changes
- University of Nebraska–Lincoln — On-Farm Research Standard Protocols
- Utah State University — On-Farm Research Guide
- ARVALIS — Résultats technico-économiques de biostimulants sur blé
This article provides product-selection and operating logic, not a legally binding application rate. Final use follows the registered label, batch documentation, water and soil analysis, and local technical guidance.