With the massive increases in fertilizer prices over the last year (DAP has trebled in price from Aug 2007 to Aug 2008), farmers need to prioritize where they will spend their money on their costs of production. Eucalyptus fertilizer trials conducted by the ICFR in SA show that fertilizer showed significant responses in only 65% of the trials conducted. The trials that showed most positive results were mainly in the Zululand region with very low clay percentage in their soils. Results from other areas are not always conclusive for fertilizer.

Growers should consider carefully whether they should spend their money on fertilizer or instead spend it on improved genetic material. Seedlings from improved seed cost approximately R200 per thousand more. One is far more likely to get a return on investment from genetic improvement at just over R300per ha rather than fertilizer at approximately R2000 per ha.


Further genetic improvements can be made by planting clonal material. Trials conducted by NCT in PMB have shown that GxU clones have out-yielded Grandis seedlings by 21%. Results such as these are common if clones are matched correctly to the specific site. The most expensive clones will cost a grower about R2000 per ha extra to plant. Is it therefore not worth rather spending R2000 on clones rather than R2000 per ha on fertilizer where results are unpredictable?

Ideally, if costs are not too limiting, growers should use clones as well as fertilizer. However if establishment budgets are limited, then investing in clones seems a far better investment than fertilizer.

The economics are simple to show that this is a good investment. Assuming a yield of 150 tons at 8 years on Nitens is expected on a particular site, changing to the correct GxN should give an increase in yield of at least 15 tons and possibly up to 30 tons. Assuming a net standing value of R350 per ton, an investment of R2000 per ha could reap rewards of a minimum of R5250 and possibly up to R10 500 per ha. Taking the time value of money into account, an IRR of above 15% per annum can be expected, which is a very good investment. All growers should therefore look carefully at planting some compartments to clones on their farms.

Contact: Bryn Pollard or Ken Leisegang at Sunshine Seedlings for further advice
H/O Number 033 390 3047

Acknowledgments to Craig Norris and Jacob Kotze of NCT for information