Background and Aims: Spatial and temporal variability of vine vigour within a vineyard block, associated with variation in soil physical and chemical properties, affects yield, and fruit and wine composition. The objectives of this study were to measure this variability and possible causes for a commercially important vineyard area in Hawke's Bay, New Zealand. Methods and Results: Three vigour classes, and measurement of vine nutrient and water status, vegetative growth and canopy attributes, yield, fruit ripening profiles, and grape and wine composition over two seasons characterised vigour variability of Cabernet Sauvignon vines growing on the 'Gimblett Gravels' area of Hawke's Bay, New Zealand. Vine nutrition and growth differed between vigour zones with extreme nitrogen deficiencies recorded. Vigour did not affect vine phenology. Normalised Difference Vegetative Index measurements quantified vigour differences. High vigour vines showed a higher yield, but fruit ripeness, wine anthocyanins and phenolics, and some sensory attributes were significantly reduced. Excessively leafy canopies associated with high vigour were responsible for these effects. Conclusions: Soil-induced vine nutrient deficiencies, rather than differences in vine water status, influenced vine vigour. Measures of vegetative growth and canopy attributes suggested negative implications of excessive shading with high vine vigour. Significance of the Study: This study showed the relative significance of nutrition in affecting vine vigour on sandy gravel soils. A good correlation between remotely sensed vigour zones, and grape and wine composition permit on-ground zonal management to minimise the negative effects of spatial variability.

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Cluster removal during the growing season is a widely utilized vineyard management practice aiming to balance crop load to the capacity of the vine to ripen the fruit. Research was undertaken over two growing seasons (2008-2009) in Hawke's Bay, a cool climate region of New Zealand, to establish the influence of different times of crop removal on Merlot vine growth and fruit and wine composition. The test vineyard was high-yielding, to 23 t/ha, and vigorous. A commercial standard of apical cluster thinning to remove 20 clusters per vine from vines with ca 44 clusters in 2008 and ca 47 in 2009, was carried out on uniform vigour, 7yo grafted Merlot vines at nine times between prebloom and six weeks post veraison. The 2009 season was naturally higher yielding. Timing of crop removal had no significant effect on vine vegetative growth in terms of enhanced shoot growth as measured by cane weights at pruning, or canopy leaf density. Time of thinning also had no effect on overall grape yield, cluster weight, and berry weight. There were limited effects on fruit ripeness in one season (2009) at the veraison time of thinning only, with increased Brix and lower TA levels. Berry anthocyanin concentrations were enhanced by cluster thinning in 2008, and more so when undertaken at or soon after veraison. There was however no influence of removal timing on anthocyanin levels and total phenolics in the wines. Grape ripeness, must and wine composition tended to respond more from crop removal at veraison than the other times evaluated. Data suggest that vine response was modified by excessive leafiness and shading.