Vineyard checkups (under revision)

Vineyard checkups. when walking into a established vineyard situation.

Health status: Tissue Analysis

• Bloom: Initial survey of nutrient status
  60 to 80 petioles from single management unit with same rootstock and scion. Sample on both sides of row before any foliar sprays or fungicides. Select an unshaded shoot, and sample near basal leaves opposite flowers. Label the vines and sample them year after year. (full bloom is defined as two-thirds cap fallen off.) Keep samples in paper bag to dry. Order full panel (N, K, Mg, Na, Cl, Zn, B) for three years, then only measure deficient nutrients unless there are changes to irrigation, pruning or trellising. Less common problems are P, Ca, Mn. Cu, Mo are fine in CA.
• Veraison: Follow-up nutrient sampling
  80 to 100 petioles from single management unit with same rootstock and scion. Select a recently matured leaf (eg. second fully expanded leaf, usually 6th to 7th from tip and color of mature leaves). Check if borderline deficiencies during bloom are in deficient range now. eg. K. Keep samples in paper bag and dry, since K, Na, Cl leach out if leaf is necrotic.
• Mid-summer: Disease Diagnosis
  Sample affected leaves (esp. B) and petioles (Na, Cl toxicity) and some unaffected leaves as baseline.

Concentration Range
Nutrient	Deficient	Marginal	Adequate	High	Toxic	Comments
N-NO3	<340	340-499	500-1200	>1200		See reference list: Calif possibly toxic range > 2000. Vigor or leaf color may be better index of N status
P %	<0.2	0.2-0.24	0.25-0.50	>0.50		Pinot noir often has values <0.2%.
K %	<1.0	1.0-1.7	1.8-3.0			When deficiency is suspected sample again in 6-8 weeks. <0.5% in petiole or 0.8% in blade confirms deficiency. Large differences in petiole K between varieties.
Ca %			1.2-2.5
Mg %	<0.3	0.3-0.39	>0.4			Values are often >0.4% with no observable toxic effects
Na %					>0.5
Cl %					>1.0-1.5	See reference list: Calif possibly toxic range > 2000. Vigor or leaf color may be better index of N status
Fe (mg/kg)			>30			Dust contamination may be present since petioles aren’t washed. Leaf symptoms more useful diagnostic aid.
Cu	<3	3-5	6-11			Fungal spray may be present. Values >15mg/kg mean surface contamination with Cu sprays.
Zn	<16	16-25	>26			Fungal spray may be present. Foliar nutrient may be present. Deficient and marginal as used in commerical labs.
Mn (mg/kg)	<20	20-29	30-60		>500	Fungal spray may be present. Foliar nutrients may be present.
B (mg/kg)	<25	26-34	35-70	71-100	>100	If in toxic range, follow up with blade analysis: value > 150 mg/kg is indicative of B toxicity.
Ni (mg/kg)						Critical values unknown.
Mo (mg/kg)						Foliar nutrients may be present to improve fruit set.

* credit: Robinson (2004), Greenspan (2005)
** Fe, Ni (no critical values) and NO3 (very variable)

Further reading:
Christensen, P. Use of Tissue Analysis in Viticulture. Proceedings of the 2004 Varietal Winegrape Production Short Course.
Christensen, P. Monitoring and Interpreting Vine Mineral Nutrition Status for Wine Grapes (2002)
Greenspan, M. Avoiding Poor Fruit Set. Wine Business Monthly.
Robinson, JB. Critical Tissue Values and Application of Nutritional Standards for Practical Use in Vineyards. Proceedings of the Soil Environment and Vine Mineral Nutrition Symposium.