The effects of 7 rootstocks (AxR#1, 110R. 5C, 3309, 420A, 1616 and 039-16) grafted to Cabernet Sauvignon (clone #8) in combination with 3 between row spacings (2, 3, and 4 m) and 2 in-row spacings (1 and 2 m) on the level of minerals in petioles sampled at full bloom and at veraison on the mineral composition of fruits at harvest were evaluated over a 3 year period (1991 to 1993) in a replicated field plot established at Oakville in 1987. 039-16 petioles had the highest level of K, Ca and NO3, whereas 420A had the lowest concentration of these minerals, the other 5 stocks being intermediate. Petiole Mg level was highest in 420A and lowest in 039-16. 039-16 fruits at harvest had the highest level of K, malate, and pH, whereas 420A fruits were lowest in these substances. Between row spacing showed no significant effects on the concentration of minerals in leaves and fruits. However, leaves from vines spaced 1 m apart within rows had lower levels of Ca and Mg than 2 m vine spacing. One m vine spaced fruits were lower in °Brix hut higher in titratable acidity and malate than 2 m vine spaced fruits. Regression analysis showed that the number of roots per unit volume of soil was positively related to the concentration of K in leaves and fruits, regardless of the rootstock used.