We tested the effects of herbaceous vegetation enhancement on the abundance and richness of plants and arthropods in a wine-producing vineyard in Israel. We compared the abundance and species richness of plants and arthropods between a plot seeded with local annual plants and an unseeded plot. We also compared soil content and grape quality parameters in seeded versus unseeded plots in the vineyard. Seeding increased plant cover and plant species richness in the spring, but reduced plant cover and did not affect species richness in summer. Arthropods, and especially parasitoids and generalist predators, were more abundant and diverse in the seeded than in the unseeded plots in spring, both on the herbaceous vegetation and on the vine foliage. Arthropods were more abundant in the herbaceous vegetation than on the vine foliage in spring, but not in summer. The soil in seeded plots was richer in ammonium nitrogen and organic matter, while the grapes were smaller and sweeter. Our findings showing a general increase in biodiversity, combined with additional considerations, led the managers of the vineyard to implement these vegetation enhancement practices in 85% of their vineyards.