COVER CROPS in South African Vineyards

CHAPTER 2 REGIONAL TRIAL SITES

TABLE 2.2. Average mean daily temperature and monthly rainfall for Stellenbosch for March 1991 to February 1993. Data supplied by the ARC Institute for Soil, Climate and Water.

Average total monthly rainfall in millimetres

Average mean daily temperature in °C

Month

January February

5.4

21.7 21.4 21.6 17.9 15.5 13.1 12.7 12.4 14.1 17.0 18.8 20.1

44.1 20.3 62.9 99.2

March

April May June

216.8 172.5

July

August

64.4 90.3 70.7 15.0 10.6

September

October

November December

Average total annual rainfall

871.9

The Coastal region represents a relatively cool area with a relatively high winter rainfall. This region receives more rain than the Breede and the Olifants River valleys. Soil types Soil at the ARC Infruitec-Nietvoorbij trial site near Stellenbosch was a medium-textured, sandy loam of a type frequently found in the cooler grapevine-growing regions. Clay content was 17%–19% at 0–300 millimetres and 19% at 300–600 millimetres. The Boschendal site had a sandy soil. Clay content was 6% at 0–300 millimetres. Blaauwklippen had a sandy to sandy clay loam soil. Clay content was 7% at 0–300 millimetres and 24% at 300–600 millimetres. Soil at Plaisir de Merle was of a sandy clay loam type, with a clay content of 23% at 0–600 millimetres. Irrigation practices Different irrigation practices were applied at different sites and for the

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