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¶ Sunflower (Helianthus annus)
¶ A: Emergence to 4 true leaves
Plant Part: Fully developed leaf
Sampling Procedure: Do not sample until plants have at least two true leaves. Collect samples from 25 to 30 plants. Collect the fully developed leaf and petiole, if available.
| Analysis | Tissue Concentration Guidelines | |||||||
| Low/Marginal Range | Sufficiency Range | Excessive, toxic? | ||||||
| Nitrogen, % N | 3.20 | - | 3.70 | 3.70 | - | 5.00 | ||
| Phosphorus, %P | 0.30 | - | 0.35 | 0.35 | - | 0.60 | ||
| Potassium, % K | 1.50 | - | 2.00 | 2.00 | - | 4.00 | ||
| Calcium, % Ca | 0.50 | - | 1.30 | 1.30 | - | 2.50 | ||
| Magnesium, % Mg | 0.15 | - | 0.25 | 0.25 | - | 0.70 | ||
| Sulfur, % S | 0.30 | - | 0.35 | 0.35 | - | 0.60 | ||
| Zinc, ppm Zn | 15 | - | 25 | 25 | - | 70 | 250 | |
| Iron, ppm Fe | 30 | - | 50 | 50 | - | 350 | ||
| Manganese, ppm Mn | 20 | - | 40 | 40 | - | 100 | ||
| Copper ppm Cu | 3 | - | 5 | 5 | - | 15 | ||
| Boron, ppm B | 15 | - | 30 | 30 | - | 50 | ||
| Nitrogen-to-sulfur ratio (N:S) | 7 | - | 10 | 10 | - | 15 | ||
| Sodium, % Na | - | 200 | - | 5000 | ||||
| Chloride, % Cl | - | - | ||||||
¶ Figure A.
¶ B: 8 true leaves to bud stage
Plant Part: Most recently matured leaf
Sampling Procedure: Collect samples from 25 to 30 plants. Begin from the top of the plant and remove the youngest, fully developed leaf and petiole - usually 4th or 5th leaf from the top.
UNDER CONSTRUCTION
| Analysis | Tissue Concentration Guidelines | |||||||
| Low/Marginal Range | Sufficiency Range | Excessive, toxic? | ||||||
| Nitrogen, % N | - | - | ||||||
| Phosphorus, %P | - | - | ||||||
| Potassium, % K | - | - | ||||||
| Calcium, % Ca | - | - | ||||||
| Magnesium, % Mg | - | - | ||||||
| Sulfur, % S | - | - | ||||||
| Zinc, ppm Zn | - | - | 250 | |||||
| Iron, ppm Fe | - | - | ||||||
| Manganese, ppm Mn | - | - | ||||||
| Copper ppm Cu | - | - | ||||||
| Boron, ppm B | - | - | ||||||
| Nitrogen-to-sulfur ratio (N:S) | - | - | ||||||
| Sodium, % Na | - | - | ||||||
| Chloride, % Cl | - | - | ||||||
¶ Figure B.
¶ C: Flowering
Plant Part: Youngest fully mature leaf
Sampling Procedure: Collect samples from 25 to 30 plants. Begin from the top of the plant and remove the youngest, fully developed leaf and petiole - usually 4th or 5th leaf from the top.
| Analysis | Tissue Concentration Guidelines | |||||||
| Low/Marginal Range | Sufficiency Range | Excessive, toxic? | ||||||
| Nitrogen, % N | 2.50 | - | 3.00 | 3.00 | - | 4.50 | ||
| Phosphorus, %P | 0.15 | - | 0.20 | 0.20 | - | 0.50 | ||
| Potassium, % K | 1.20 | - | 1.70 | 1.70 | - | 3.50 | ||
| Calcium, % Ca | 0.50 | - | 1.30 | 1.30 | - | 2.50 | ||
| Magnesium, % Mg | 0.15 | - | 0.25 | 0.25 | - | 0.70 | ||
| Sulfur, % S | 0.20 | - | 0.25 | 0.25 | - | 0.55 | ||
| Zinc, ppm Zn | 12 | - | 20 | 20 | - | 50 | 250 | |
| Iron, ppm Fe | 30 | - | 50 | 50 | - | 350 | ||
| Manganese, ppm Mn | 20 | - | 40 | 40 | - | 100 | ||
| Copper ppm Cu | 3 | - | 5 | 5 | - | 15 | ||
| Boron, ppm B | 15 | - | 30 | 30 | - | 50 | ||
| Nitrogen-to-sulfur ratio (N:S) | 7 | - | 10 | 10 | - | 15 | ||
| Sodium, % Na | - | 200 | - | 5000 | ||||
| Chloride, % Cl | - | - | ||||||
¶ Figure C.
