Technical Yearbook 2023

MAY

Gen-Z interplanting project: preliminary results – Olifants River By Gert Engelbrecht

Most role players in the industry are probably already aware of Vinpro’s Gen-Z vineyard project. The objective of this project is to establish experimental plots in commercial vineyards and then collect information from these plots to share with producers via a more practical approach at demo sites and field day sessions. The project is multidisciplinary and includes inter alia rootstock trials, clone gardens and cover crop plots. With the commencement of the project in 2015, it was decided in the Olifants River to focus specifically on

alternative cultivars not widely grown in the region. These include white and red cultivars that show potential to produce good yield and quality in the region’s hot conditions with its sharp heat spikes. The first grafted vines were already planted between commercial blocks in 2016. The amount varies between 150 and 250 vines per trial which yields enough grapes for the producer cellars in the region to make wine from. The project is still ongoing and would not be possible without the cooperation of a large group of people. This includes the producers who are willing to plant the grafted vines, cultivate and deliver the grapes separately, as well as viticulturists who assist with planning and intakes. Furthermore, the winemakers who make time and space in their cellars during harvest time, plus facilities and man-hours which are made available by Namaqua Wines and Lutzville Vineyards. Vititec has also been very helpful

TABLE 1. Tasting notes, comments and basic production data per cultivar.

Cultivar

Comments

Tasting notes

Production data

Perfume, pleasant mouthfeel, like cool-climate Chenin, good acidity and tropical flavours.

Karoo plains, sandy soil, 38 t/ha (mechanically pruned), 22°B, 3.3 pH, 7.6 acidity. Vredendal, red sandy loam soil, very high yield, 19.3°B, 3.4 pH, 6.8 acidity. Koekenaap, yellow-brown sandy soil, 25 t/ha, late ripener, 19.3°B, 3.4 pH, 5.7 acidity. Spruitdrift, shallow sandy soil, 12 t/ha (potentially 20 t/ha), 24.5°B, 3.6 pH, 5 acidity. Vredendal, Karoo terraces with rock, 10 t/ha, 23°B, 3.6 pH, 4.5 acidity. Vredendal, sandy soil with loam fraction, 25 t/ha, 24.5°B, 3.6 pH, 6.9 acidity. Lutzville, alluvial silt soil, 30 t/ha, 24.6°B, 3.6 pH, 6 acidity. Liebendal, red sandy soil, 25 t/ha and more, 25°B, 3.7 pH, 5.5 acidity. Lutzville, alluvial silt soil, 40 t/ha, 24°B, 3.4 pH, 6.6 acidity.

Ripens very early, will blend well with Chenin blanc and Chardonnay.

Verdelho

Stone fruit, short palate, blending cultivar.

Macabeau

Ripens mid- to late season.

Vermentino Large berries and bunches, low recovery. Tempranillo Ripens early, large bunches, strong vigour.

Good length and mouthfeel, citrus, lime, good acidity, floral, dried fruit. Medium-full style, berries, red and dark fruit flavours, dry tannin sensation. Merlot, Petit Verdot, green tannin, good colour, berry and red fruit flavours. High acidity and good tannin, spicy, light red style. Medium-full style, very good colour, red fruit flavours, soft tannins with berry, red fruit and plum flavours, good length. Dark colour, spicy, prominent tannins, vibrant red fruit, dry, high acidity, dark fruit. Medium-full style, medium colour, cherry, plum, herbaceous and sweet fruit flavours, refined.

Grapes similar to Merlot, long bearers necessary for yield, prone to green flavours, harvest ripe.

Carménère

Carignan

Ripens late.

Very strong vigour, ripens mid- to late season.

Marselan

Durif

Very high yield, mid- to late season.

Sangiovese Medium vigour, big bunches and berries, late ripener.

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TECHNICAL YEARBOOK 2023