Can you grow without fertiliser?
With synthetic fertiliser you fix a shortage within days. Without it, nitrogen is released when the soil is ready. FairGrow works out, day by day, whether that is in time for your crop.
Heavy models under the hood, one clear answer for you
Behind every day on the card sits a model that links weather, soil, decomposition and crop demand. That is our job. Yours is growing food. So you only see what you need: does the nitrogen arrive in time, and if not, when not.
Three days short of nitrogen. Weather, soil and your compost are already included.
What we do
Collect the data, build the models and run them every day with the weather at your location.
What you do
Enter what you applied, when, and what you grow. That is all. A sensor or soil test is welcome, not required.
What you get back
One answer per day: in time, or not. No formulas, no spreadsheet.
Not “is there enough”, but “will it come in time”
A grower using fertiliser asks whether there is enough in the soil right now. Without fertiliser that is the wrong question: a shortage you see in July can no longer be fixed in July. So FairGrow runs forward from today, day by day, adding what your sources release and subtracting what the crop takes up.
- If the balance drops below zero, you see on which day, and how long the shortage lasts.
- Cold soil explains a standstill. When the ground is frozen nothing is released, so adding more does not help.
- Too much at once is a signal too: leaching is likely and a catch crop is a good idea.
Nitrogen balance, the next 16 days
Four layers, every day
Measure your green manure with a folding ruler
How much nitrogen is in your green manure? Measure the height of three to five plants, choose how dense the crop stands, and read it off. The numbers come from the NMI chart for nitrogen content of green manures.
- Spring or autumn makes a big difference: if you work it in during autumn, you lose about half to leaching over the winter.
- Clover and vetch fix nitrogen from the air themselves.
- Try it here. The same calculator is in FairGrow, and nothing is stored.
Green manure calculator
Two tools alongside
The lead-time calendar
How many weeks ahead does each source need at today’s soil temperature? That tells you when to apply compost or manure so it is in time.
If a source has more than 25 times as much carbon as nitrogen, it actually locks up nitrogen in the first year. Then FairGrow gives a warning instead of a number.
The balance across the rotation
Nitrogen, phosphate, potash, magnesium and sulphur: what goes onto your field against what the harvest removes, at the yield you expect. Without fertiliser you do not close a phosphate or potash shortage within one season.
Plus organic matter: do you stay above roughly 2,000 kg of effective organic matter per hectare per year?
What FairGrow watches for you
Sources
What it does now, and what is coming
Today
Eleven crops plus a general profile: tomato, cucumber, sweet pepper, lettuce, cabbage, potato, onion, strawberry, courgette, bean and maize. The calculation runs to the end of the weather forecast, 16 days ahead, and the card says so. For now in Dutch and English.
Coming
Calculating to harvest instead of 16 days, the full library of 135 crops, and the other 55 languages. See what we are building now.
Answered briefly
Is this only for organic growers?
No. It is for anyone who wants to use less or no fertiliser and wants to know whether compost, manure and green manures feed the crop in time.
Do I need a soil sensor?
No. Without a sensor, FairGrow uses the soil temperature and soil moisture from the weather at your location. Your own sensor or a soil analysis makes the calculation more precise, and the card shows how much confidence it deserves.
How does this relate to the regular nitrogen balance?
The nitrogen balance looks at today and the next thirty days: is there enough now? This card asks whether it is released in time. With fertiliser the first question is enough, without fertiliser it is not.
Where do I record my compost and manure?
In the nitrogen card on your dashboard: per application the type, the amount and the date. You keep your soil analyses in crop registration.