Fertility of Vinifera Grapes in NC SERA 2008 Meeting Fertility of Vinifera Grapes in NC SERA 2008 Meeting David H. Hardy and John Havlin NCDA&CS and NC State

NC Wine Industry is Growing wineries NC Grape Council created wineries wineries Today- over 70 wineries

NCDA Grape Recommendations Soil testing –Muscadine grapes Plant tissue –Vinifera grapes at full bloom Where did they come from???

P Grape Recommendation

K Grape Recommendation

Present Liming & Fertilization

Objectives 1.Evaluate nutrient status in common red and white vinifera varieties 2.Establish critical nutrient concentration ranges in both leaf and petiole samples 3.Correlate plant nutrient status with soil test information

Effect of topography Leaf-cluster position Mature leaf at veraison Effect of topography Leaf-cluster position Mature leaf at veraison Additional Considerations

1 Black Wolf 12 Round Peak 13 Shelton 16 Surry CC 1 Black Wolf 12 Round Peak 13 Shelton 16 Surry CC 3Creek Side 6Grove 8Iron Gate 3Creek Side 6Grove 8Iron Gate 2 Buck Shoals 2 Buck Shoals 8 Laurel Gray 8 Laurel Gray 9 Raffaldini 9 Raffaldini 14 South Creek 15 South Mountain 4 Flint Hill 4 Flint Hill 7 Hanover Park 7 Hanover Park 10 RagApple 11 RayLen

Cabernet Sauvignon 15 Chardonnay 14 Merlot 11 Cabernet Franc 11 Syrah 10 Viognier 7 Chamborcin 6 Sangiovese 5 Sauvignon Blanc 3 Chardonell 2 Chancellor 1

6 cores per variety 4 – 8” 0 – 4” 8 – 24” Sampling away from fertilizer or lime application Cecil fine sandy loam Fine, kaolinitic, thermic Typic Kandhapludults

Upper 4 inch depth Little variability

Upper 4 inch depth Little variability Good lime practices

NC Vineyard Soils

Mehlich STP ppm

Mehlich 3 K ppm

FB and veraison- all sites 4 intensive sites- every 2 wk

Laurel Grey select varieties Petiole N Concentration Petiole N- FB 0 – 0.39 D 0.4 – 0.79 L 0.8 – 1.0 S 1.01 – 1.25 H 1.26 – 1.5 E FB

Laurel Grey select varieties Petiole P Concentration Petiole P- FB 0 – 0.09 D 0.1 – 0.14 L 0.15 – 0.6 S 0.61 – 1.0 H 1.01 – 2.0 E FB

Laurel Grey select varieties Petiole K Concentration Petiole K- FB 0 – 0.99 D 1.0 – 1.49 L 1.5 – 3.5 S 3.51 – 4.5 H 4.51 – 5.5 E FB

Selected Tissue Levels Petiole P > 0.40 # Sample Sites % Sample Sites Petiole K > 2.50 # Sample Sites % Sample Sites P = 0.15 – 0.6 Sufficient K= 1.5 – 3.5 Sufficient

Nutrient Content Relative to Cluster Position

Topographic Effects on Nutrient Content

Maintain primary objectives – *** increase # mountain sites 2.Quantify sampling error 3.Draft diagnostic nutrient ranges (???) 4. Assess nutrient response 1.Maintain primary objectives – *** increase # mountain sites 2.Quantify sampling error 3.Draft diagnostic nutrient ranges (???) 4. Assess nutrient response