Manure Application Rate Calculator
Sizes a manure dressing to the nitrogen your crop needs.
Share sends a link that reopens these numbers. Copy details pastes the full breakdown as a list.
The formula
rate (t/ha) = N wanted ÷ (N in the manure × availability)
Only part of the nitrogen in manure reaches the crop in the first year. The rest stays in slower forms or is lost.
What to watch out for
Manure varies with the animal, bedding, storage and dilution, so a test is worth having. Weigh a spreader load to check what is really going on. For slurry, kg per m³ and t/ha treat one cubic metre as about one tonne.
Frequently Asked Questions
How much manure gives 50 kg/ha of available nitrogen?
At 6 kg N per tonne and 30% availability, 27.8 t/ha.
Why not count all the nitrogen?
Much of it is in organic forms that release over years, and some is lost as ammonia on spreading. Counting all of it would leave the crop short.