UK Kelp Biostimulant Grower Savings Calculator

Based on our current trial data, WK26-C has the potential to reduce nitrogen requirements by 30% without impacting yields. Given so much volatility in today's fertiliser prices, we would like to know if this is something you would be interested in exploring. 

Winter Wheat Example: WK26-C is applied at 2 litres per hectare, across three applications during the growing season — a total of 6 litres per hectare at £7/L, giving a full-season program cost of £42 per hectare. Using our calculator and today's fertiliser pricing, this would amount to a saving of £3,235. 

You can find our nutrient use efficiency data sheet here.

< TerraMara WK26-C — Fertiliser Savings Calculator
TerraMara
WK26-C Cultivated Kelp Biostimulant
× Fertiliser Savings Calculator
Understand whether WK26-C can reduce your nitrogen costs — and by how much — at today's fertiliser prices.
Grower decision tool WK26-C Cultivated Kelp Biostimulant
Nitrogen use efficiency model
Based on AHDB RB209 guidance
This calculator helps you estimate the net fertiliser cost saving you could achieve by incorporating WK26-C into your programme. Enter your crop, your current nitrogen rate, and today's fertiliser price to see whether WK26-C pays — and at what fertiliser price level it stops paying. The model is based on a single agronomic assumption: that WK26-C improves nitrogen use efficiency sufficiently to allow you to reduce applied nitrogen by a set percentage without sacrificing yield. Adjust the N reduction slider to reflect your own trial experience or risk appetite.
How to use this tool
1
Set your fertiliser pricesUse the price panel below to enter current spot prices, or click "Refresh via AI" to auto-populate from AHDB data.
2
Select your crop & N productChoose the crop you're evaluating. RB209-recommended N rates load automatically as a starting point.
3
Adjust your nitrogen rateOverride the RB209 default with your actual planned rate if it differs from the guide.
4
Read your breakeven priceThe highlighted box shows the fertiliser price at which WK26-C stops delivering a cost saving — your buffer from today's market.
Current fertiliser prices
AHDB prices ↗
Ammonium nitrate (UK)
34.5% N · UK-produced
£/t
Ammonium nitrate (imported)
34.5% N · imported AN
£/t
Granular urea
46% N · granular
£/t
Liquid UAN (UAN32)
30% N w/w · liquid
£/t
DAP
46% P₂O₅ · 18% N
£/t
MOP / potash
60% K₂O · muriate of potash
£/t
Your inputs
Crop type
Nitrogen product
Your nitrogen rate 180 kg N/ha
RB209 guide rate loaded as default. Adjust to your planned application.
Area to treat 200 ha
N reduction with WK26-C 30%
Current efficacy data suggests 30%. Adjust to test sensitivity.
WK26-C rate per application 2.0 L/ha
Applications per season 3
WK26-C is typically applied 1–3 times across the growing season. Total volume = rate × applications.
WK26-C price £7.00/L
Cost breakdown — per hectare
Net saving per hectare across a range of fertiliser prices
Net saving/ha — above zero means WK26-C is cost beneficial Breakeven — zero net saving Today's fertiliser price
Fertiliser prices sourced from AHDB GB Fertiliser Price series — ahdb.org.uk/GB-fertiliser-prices.
Nitrogen application rates based on AHDB RB209 Nutrient Management Guide (Section 4: Arable crops, 2023 edition).
WK26-C efficacy assumption: 30% N reduction with maintained yields — based on TerraMara trial data. Growers should evaluate against their own soil, variety and agronomic conditions.
TerraMara
WK26-C Cultivated Kelp Biostimulant
terramara.co.uk

Request our biostimulant efficacy data

We’re working with partners at Atlantic Mariculture, James Hutton Institute and UK AgriTech Centre, with funding from Innovate UK, to develop a range of low-energy kelp-based biostimulants and feed additives.

To request our wider efficacy data, or to discuss trial opportunities, simply complete our contact form and we’ll be in touch.

If you have any questions, please get in touch with kerr@algapelago.com directly.