Chardonnay grape vines grown in lysimeters were given a surface application of ¹⁵N-depleted residue of a five species winter annual cover crop mix containing four legumes and one grass species.  Grape leaf ¹⁵N was measured over a fourteen-week period, after which the whole vines were destructively sampled and ¹⁵N content and biomass measurements were taken of the roots, stems, shoots, and leaves.  Grape leaf percent N derived from the cover crop residue (%Ndfcc) reached 32% in the treated vines after only two weeks, dropping to about 25% by four weeks and remaining at about that level for the remainder of the experiment.  In the first two weeks grape leaf %N rose from 2.9% to 4.2% in vines given ¹⁵N-depleted cover crop residue and from 3.0% to 3.6% in vines given non-¹⁵N-depleted residue while there was no significant increase of leaf %N in vines given no-cover crop residue.  Leaf %N declined steadily to 1.7% by fourteen weeks in all vines.  After 14 weeks, %Ndfcc was 20-22% in leaves, shoots, and roots but only 14% in stems.  Sixty-four percent of cover crop-released nitrogen was recovered in the grapevines after 14 weeks.  This study shows that an untilled cover crop mix containing legumes can provide adequate nitrogen for grapevine growth when residue is made available to the root zone of the vine.