Cover crops can provide important benefits to agroecosystems, though growing cover crops in vineyards can also have potential drawbacks. Such drawbacks can vary by site, grapevine genotype, and cover-crop species. Deleterious effects can include decreased vine vigor and yield. Effects of cover crops that are considered drawbacks at one site may be considered benefits at other sites. The objective of this study was to investigate the influence of seven different alleyway cover-crop treatments on soil moisture and vine response in western Oregon vineyards. The main goal was to determine whether various cover-crop mixtures grown in vineyard alleyways and mowed in the spring and summer would compete with grapevines for water and/or nutrients.