It is prohibited to plant grains, legumes, or vegetables next to grapes, or vice-versa. If this occurred, one may not eat or benefit from the resulting crops. This prohibition is limited to the Land of Israel and does not apply in the diaspora, except in rare cases. What is the reason for the prohibition? Perhaps because grain and wine are fundamentally different. Grain is an essential we need to survive, while wine is a luxury that gives us pleasure. Mixing them is not appropriate. If we related to wine the way we relate to grain, we might become alcoholics, and if we related to grain the way we relate to wine, we would relax at work.
