WINETECH Technical Yearbook 2019

this year and looks very promising. It is exceptionally drought tolerant and produces good material. It will be further evaluated in forthcoming seasons. Sowing rate: 3.5-4 kg/ha. • Mixtures of cereals, for example triticale or forage rye and vetch (Photo 3), fared very well everywhere. It resulted in good weed suppression and produced large amounts of material. The given soil type

will determine which cereal should be present in the mixture. • Among the cereals saia oats also fared very well resulting in good material and excellent weed suppression. • The clovers fared poorly and were overgrown by weeds, because they only really start growing late in the season. They are however better options as cover crops on the berms.

• The white mustard variety, namely Sito (Photo 4), produced very good results. It produced ample biomass and provided very good weed suppression. This cover crop fared extremely well despite last year’s drought. • Soil type also played a significant role in cover crop performance, especially in the Wellington area where lupins fared much better than vetch on the weathered

granite soils. On the weathered shale soils vetch came into its own and produced very good material together with Barpower forage rye. It is therefore extremely important to keep soil type in mind when selecting crops. • Large differences occurred where 100 kg LAN/ha fertiliser was given at four to six leaf stage compared to rows with no fertiliser. Often this doubled the production of material. • Cheeseweed and rye grass were the two weeds that competed most with the cover crops on the demo plots. These weeds can be controlled by selecting cover crops that provide good weed suppression. Some of the results, findings and/or recommendations from the demo sites can be found in future on the Gen-Z website ( www.genz.co.za ), which is currently under construction. ACKNOWLEDGEMENTS: Our producers/farm managers who hosted these demo plots. Barenbrug (Jaco Kellerman and Ivan Jansen van Rensburg), as well as Agricol (Christof Muller) for the donations, advice, time and involvement in farmers’ days.

PHOTO 5. Johan de Jager, Vinpro soil scientist, on the Sito demo plot in Hermon.

– For more information, contact Francois Viljoen at viljoenf@vinpro.co.za.