By making the most of the nutrient content of organic manures, savings can be made on inorganic fertiliser costs and environmental losses can be reduced.
Organic Manure Use in Arable Systems
To make the best use of manure and inorganic fertiliser N inputs, both nutrient supplies need to be integrated.
In order to make the most of available nutrients in organic manures what should I do?
Know the nutrient content of the manures and slurries that are applied
Apply manures evenly at a known rate
Plough in any manures applied quickly or use a low level application method to minimise losses through leaching, and get the nutrients where they need to be to help crop growth
Apply in spring where possible to reduce leaching losses and to allow the crop to use the manures most effectively
Take the nutrient supply of manures into account when planning artificial fertiliser applications, don’t apply it twice
Using slurries and manures on grassland could provide up to 20% of the N, 100% of the P and 80% of the K needed by the grassland for silage or hay production.
Top tips for applying organic manures to grassland
To make the best use of N, apply it when the crop is actively growing and the N demand is greatest (usually late winter / early spring.)
Control the application rate to control smothering / scorch of grassland and poor silage quality.
Target application rates should always relate to the nutrient requirements of the next crop.
Using manures on grazing land can lead to problems – apply it where possible to ground for silage.
How does the spreading method impact on available nutrients?
Ensuring that what you want to be available to the crop during the growing season is applied at a time and in a way that the crop can use it, will mean that you can reduce artificial fertiliser use (and therefore costs).
Livestock manures are a valuable source of nutrients in many organic rotations. Making best use of these nutrients can contribute to better profit margins and minimise pollution risks on your farm. Read more here.
For more information on how to integrate organic manure use with inorganic fertiliser use, click here to download a copy of MANNER, an interactive tool designed to accurately predict the fertiliser nitrogen values of organic manure on a field specific basis.
Want to find out more about manure use efficiency, improve your nutrient management planning and explore the different options available to you when looking at manures and slurries? Click here to visit our Think Manures section to proactively plan nutrient applications.
To download RB209 to plan crop requirements of nutrients and adjust fertiliser for manure applications please click here.
Interested in looking at the different types of organic manures which can be used to save money on bagged fertilisers well as improving soil organic matter? Click here to read the Nutrient Wise Demo Factsheet.
Want to know more about the benefits of digestate? Click here to read the Nutrient Wise Factsheet.
Could you benefit from green waste compost? It largely comes from municipal green waste and is usually composted on the farm where it is used. To find out more about it click here.
James Johns farms 450 acres outside Truro in Cornwall. Mr Johns recently invested in a trailing shoe slurry applicator and a GPS guidance systems to make best use of the slurry from his dairy cows.
