There have been some fantastic crop yields reported this year. Early harvested sugar beet crops are yielding particularly well, with 100t/ha already talked about and plenty of growth to come from crops still in the ground. Forage maize crops are also performing very well, as did the hybrid rye crops foraged earlier this year. The cereal harvest was clearly incredibly frustrating with the stop, start and protracted duration but it did include some very high yielding first wheats. However, second wheats and barley crops fared less well.
So, why am I talking about yield performance? Clearly the positives are great to hear and vital for profitable business, but they must also be understood in regard to the phosphate and potash that is removed from the soil by these yields. It's so important to understand this to be able to maintain the fertility in your soils. If you look at the table below, you can see the influence yield has on P & K removal. These figures are from the Nutrient Management Guide (RB209), except for hybrid rye which come from our replicated variety trials for the last two harvests.
Obviously, the other side is that if you had fields where the yields were lower than normal, the offtakes would also be lower.Accurately taking account of your yields this year, and including any extra or lower removal in this year's P & K applications, will significantly improve the management of your soils.To help accurately calculate your removals and plan this year's applications, please use the Potash Development Association (PDA) Calculator. It will also highlight the nutrients required to build your soil levels if you are below the target levels for arable and forage crops of P Index 2 and K index 2-.
Alternatively, you can use the SOYL Calculator which shows the P & K removal over the rotation.If you need any further help with this, please speak to your local Frontier or SOYL contact.
Once you've worked out your P & K requirements for this year, do make sure you are using good quality, water soluble materials where the nutrients are readily available to your crops.Along with the normal straight fertilisers (TSP, DAP & MOP), this also includes PK and NPK products and the organic materials such as livestock manures, digestate and sludges.There are other materials on the market, but before you buy them be sure to question the availability of the nutrients they contain and the subsequent value for money they represent for your farm.
Edward Downing
National crop nutrition technical manager
For specific advice for your business related to this blog or any other aspect of crop production get in touch with Frontier.