Technical Yearbook 2023

Vineyard information of the 2019 plantings on Alvi’s Drift Cultivars: Chenin blanc/Ruggeri

Merlot/Paulsen Chardonnay/8-7 Pinot noir/Paulsen

Year planted:

2019

Spacing: Irrigation:

2.4 m x 1.2 m

4 L/hour NOVAP dripper/regulator (2.4 m x 1.2 m spacing)

NOVAP underground irrigation The firm NOVAP’s name is derived from the concept of “No Evaporation”. The NOVAP sub-surface water diffuser facilitates the wetting of the deeper-lying root system of vines (and any other crop). As no irrigation water is exposed directly to the soil surface or atmosphere, water losses through evapotranspiration are dramatically reduced. NOVAP is the brainchild of Jan Nortjé, who is an innovator of note on various fronts. He realised that the evaporation of water with aboveground irrigation and the blockage of underground drippers are major problems, and focused his research on resolving this. A look at the NOVAP system Simplified, the system consists of the following: • Black main supply line pipe. • Dripper/regulator (4 or 8 L/hour), fitted to the main supply line pipe (which is entirely above the soil surface). • 6 mm microtube which connects the dripper/regulator and the NOVAP diffuser with each other. • A NOVAP sub-surface diffuser which is filled with hydrophobic silica.

Schematic representation of the installation of the NOVAP system.

Installation of the system • Dig a hole of 180 - 200 mm deep in the middle between vines (at Alvi’s Drift this is 600 mm from the vines). • Place the NOVAP diffuser in the hole with the vertical pipe positioned upright with the top uncovered, and refill the hole with soil. • Connect the dripper/regulator and diffuser using the microtube. In the case of new plantings, the microtube should not be connected with the diffuser. Let the tube lie on the soil surface initially so that the water applied is readily available for the roots of the developing young vine. It is only connected once the vines’ shoot growth reaches the cordon wire.

The installation at Alvi’s Drift has been done on large scale.

Irrigation of young vines in the first stage after planting (the diffuser is not yet connected).

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TECHNICAL YEARBOOK 2023