Wine grape producers witnessed the performance of cover crops on different soil types in September and October thanks to the Gen-Z Vineyard Project, hosted by Vinpro. This year, the cover crop demo’s included site visits to the Swartland, Stellenbosch and Breedekloof regions.
“The Gen-Z cover crop demo sessions facilitated discussions and information sharing between producers, viticulturists and vineyard managers,” says Emma Carkeek, Gen-Z viticulturist. “This includes suitability of cover crop species to specific soil types, effective weed suppression and the effect of cover crops on soil health.”
Ivan Jansen van Rensburg of Barenbrug, who sponsored cover crop seeds for the project, says Gen-Z allows them to show producers which cover crops are best suited to specific areas and soil types. “Cover crops perform many functions, including improving soil health. It is evident that solutions do not only come from bottles, but from nature itself.”
He says the goals, challenges and conditions of each producer must be taken into account when selecting cover crops to obtain the best possible results.
At Heldersig, for example, white mustard showed excellent growth and provided good weed suppression. Forage rye and bitter lupia performed well on the weathered coarse granite soils at Olifantskop.
On the Oakleaf soils at Kanonkop, the mixture of forage rye and white mustard, as well as the application of medics was particularly successful. On the sandy loam soils at Klipdrift in Rawsonville, forage rye showed outstanding growth, as did the saia oats.
“The trials show that cover crops are site specific, so we would recommend that producers trial one or two in their vineyards to determine which mixes work best and allow for rotation of mixes to cultivate diversity,” says Emma.
There has been an increased focus on cover crops and its benefits. “While we know more now than we did a few years ago, more research is needed on the effects of species and mixtures on soil microbial populations, nutrient cycling and water usage,” she says.
For more information on the Gen-Z Vineyard Project contact Emma Carkeek at tel 021 276 3212, e-mail firstname.lastname@example.org.