FERTILISER IS EXPENSIVE – DON’T WASTE IT!
■ Make sure that your soils do not already have enough of the nutrients contained in your fertiliser.
■ Don’t use fertiliser blends containing three or more nutrients when a single-nutrient fertiliser will do.
■ Apply fertiliser correctly and at the right time for plants to make the best use of it. Then apply technology as far as possible.
Test your soil. It’s the only way to know what fertiliser to use, or how much lime or gypsum you need. No farmer would add oil to his bakkie engine without first examining the dipstick. Applying fertiliser without a soil test is the same.
In the laboratory, only a teaspoonful soil is tested. This represents many thousands of tons of soil. About 80% of all mistakes with soil testing happen because the sample was taken incorrectly. Your fertiliser representative usually takes samples, but you must make sure it’s done correctly – you’re paying for it, after all. Remember, a poorly taken soil sample is usually worse than no sample at all! First, get the depth of the samples right: row crops 150mm; pastures 100mm; tree crops and sugar cane 200mm. Take enough sub-samples for each sample submitted to the lab. This also applies to grid (“precision”)
