Ive heard that grafting a citrus variety can affect the flavor. Does that mean that if I graft an orange onto a grapefruit rootstock, the oranges will acquire a grapefruit flavor?

A: No, each variety will always have the same basic flavor, regardless of rootstock. But the rootstock chosen will affect the intensity of the flavor, as well as the sweetness-to-sourness ratio. Generally, less vigorous rootstocks (Poncirus trifoliata, Sour orange, citrumelo) stocks give a richer-flavored fruit. Very vigorous stocks (rough lemon, volkameriana, Rangpur) give a more bland, diluted-tasting fruit. In the questioners example, grapefruit roots will cause the orange scion to produce bland-flavored fruit.

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