SHORT TERM TECHNIQUES
The practices evaluated below are fertilisation, irrigation, winter pruning, canopy management, weed control and crop protection. Figure 2 shows that the points awarded for maintenance fertilisation, with the exception of Paarl and the Little Karoo (80 %), are very disappointing. In Olifants River (50 %), Orange River (52 %), Robertson (58 %), Stellenbosch (60 %), Malmesbury (65 %) and Worcester (67 %) more attention to this practice will stand producers in good stead.
Too little or too much fertilisation also influences the vigour of vines and eventually also the final quality of the grapes and wine. Except for the short term disadvantages of excessive fertilisation (overprolific growth, rot, etcetera) there are long term detrimental consequences such as infertility caused by an overly dense canopy.
The direct cost per hectare of fertilisation, and the percentage this constitutes of total production cost per hectare for the 1998 and 1999 production year, are as follows:
FERTILISATION COST (R / ha)
% OF TOTAL PRODUCTION COST
From this figure one may deduct that the cost of fertilisation differs from year to year. However, in none of the districts the fertilisation cost exceeds the maximum level of 8 % of production cost. It is clear, furthermore, that over- or underfertilisation does not make a large contribution to the total production cost per hectare. The result should rather be quantified in the quality and therefore the sales price of the wine.
In this category vigour is evaluated in the light of soil potential, evenness of the block, appearance of the foliage during ripening with a view to wine quality, appearance of the crop during ripening and the general appearance of the farm.
A subsection which is heavily weighted with regard to allocation of points, is the appearance of the crop during ripening. The following aspects are evaluated:
- berry colour
- turgor (freshness, stressed or wilted bunches, bloatedness)
- other damage that may harm quality / quantity
- distribution of bunches
- berry, bunch size not true to type
- quality of crop for wine purpose
Figure 3 shows that the regions generally fared well in this section. The following points were allocated: Stellenbosch (90 %), the Little Karoo (86 %), Paarl (83 %), Olifants River (83 %), Worcester (82 %), Orange River (79 %), Robertson (77 %) and Malmesbury (72 %).
The best application of natural resources as well as the application of short and long term practices with a view to the cultivation of high quality wine grapes are the most important aspects to be evaluated. In the light of the market demand for quality wines and the growth in the demand for wines made from noble cultivars, vineyard practice evaluation presents an excellent opportunity to obtain the opinion of a panel of specialists concerning your own practices. All participants receive the judging panel’s comments to enable them to adjust and improve their vineyard practices.
The evaluation is also a valuable extension tool since workshops or farmers’ days are held annually at the winning blocks in the various districts. Featured are demonstrations and critical discussions of the correct application of the various practices, as well as other topical and relevant subjects concerning the cultivation of wine grapes.
VINEYARD PRACTICE EVALUATION 2001
In 2001 the evaluation of vineyard blocks is continued in all eight KWV districts. Interested parties who would like to enter may contact the following convenors in the various districts:
Orange River Dirk Malan 082 495 7999
Olifants River Jeff Joubert 083 455 5190
Malmesbury Johan Viljoen 082 890 7446
Paarl Bennie Liebenberg 083 455 5197
Little Karoo Stephan Joubert 083 650 5590
Robertson Briaan Stipp 083 455 5196
Stellenbosch Cobus van Graan 082 650 4404
Worcester Schalk du Toit 083 303 0530