ReStory narrator: Ernst Höll
In 2002, when I had to replant a six-year-old sugar cane land, I started thinking about what we strip out of the soil and what we replenish. With a decreasing number of years between rotations, declining yields and water infiltration problems, I knew that something had to be done.
Biological consultant Ronald Schroder convinced me in 2003 to start with a limited trial on DRIS (Diagnosis Recommendation and Integrated System) to identify imbalances, deficiencies and excesses in the crop nutrients and soil. Results indicated low calcium and high magnesium – soil that lack air- and waterholding capacity.
After receiving these results, we started with a poorly performing plot, correcting the calcium and magnesium levels and later adding gypsum to increase waterholding capacity. Further analyses were done in 2005 and more corrective measures were applied. In 2006, we had a suger cane yield of 126tc/ha. After more corrective measures, yields remained consistent at 100-105tc/ha between 2008 and 2011.
However, I knew we could do more to improve the yields and our next phase in the process was to improve soil life. I decided, in consultation with Dr Nico van Vuuren (Director of SoilTech) to improve the soil biology with compost tea. This tea is brewed on the farm and applied through the irrigation system at specific times during planting. After applying the compost tea, yields dramatically improved to 120tc/ha in 2012.
Benefits that we saw, included yields at the same rate of the first cut, in 16-year-old cane, as well as reducing costs of ploughing and planting as the crops did not need to be replanted as frequently.
Although there is never a magic silver bullet, I have experienced soil correction over time using biological methods does yield results even though it takes time.