2021 Autumn Seed Catalogue

43 CROP NUTRITION The acknowledgement that current practises are unsustainable in the long-term has seen the growth in conservation agriculture and a much greater focus on improving the soils fertility and natural health. Restoring and improving soils will not be a short-term project and in reality we are looking at improving them for future generations rather than our own. However, we still need to be producing crops in an efficient and financially viable manner on the same fields and we therefore need to be tailoring the nutrition of crops in as much detail as possible. The use of soil and tissue sampling to help identify potential issues and any sub-clinical deficiencies is the first step. These analyses will not only show levels of nutrients but also allow agronomists to predict possible problems from not only a lack but also a surplus of certain elements and the ratios that they have to each other. Macro elements (nitrogen, phosphate, potassium, sulphur, calcium and magnesium) are often best addressed through soil application in the first instance while micro nutrients can often be corrected through the use of foliar products. Nutrients such as manganese and copper are widely deficient across large areas of the UK often as a result of soil type and can have a significant impact on crop potential. Every field can have its own strengths and weaknesses so there is no one answer. Increasingly the evidence of yield benefits of applying alternate forms of nitrogen through the leaf alongside other key elements is growing. The adage of “too much of a good thing” can often be very true and the best crop nutrition is not about applying plenty, but more a point of applying targeted well formulated products which can make available the nutrients the crop requires when it needs them. As we understand more about crop physiology we begin to understand more about the subtle effects different forms of nutrients may have on the growth habit of plants and what this means for crop yield which will become ever more important moving forward. Successful crop nutrition is the backbone of good agronomy. However, the complexity and interactions of the various macro and micro elements can result in making the correct decisions and course of action very difficult to identify. For the last four decades the industry has relied on relatively large inputs of manufactured nitrogen to obtain high crop yields from varieties bred to respond to this. But at the same time we have seen a reduction of soil organic matter and inherent fertility through our cropping and cultivation practises due to the over reliance on inorganic sources of nitrogen (N), carbon release from the soil and in many cases a failure to put anything back; practises which only fuelled the need for further inorganic inputs. Nitrogen will always have a fundamental role in crop production but if not in correct balance with other nutrients and soil biota its value is often wasted. Map Plan | April 08, 2019