Cranberry Nutrition: An A Z Guide Joan R. Davenport Soil Scientist Washington State University
Soil Derived Plant Essential Elements Macro Micro Nitrogen (N) Phosphorus (P) Sulfur (S) Potassium (K) Calcium (Ca) Magnesium (Mg) Iron (Fe) Copper (Cu) Zinc (Zn) Managanese (Mn) Boron (B) Chloride (Cl) Molybdenum (Mo) Nickel (Ni)
Soil Derived Cranberry Essential Elements Macro Micro Nitrogen (N) Phosphorus (P) Sulfur (S) Potassium (K) Calcium (Ca) Magnesium (Mg) Iron (Fe) Copper (Cu) Zinc (Zn) Managanese (Mn) Boron (B) Chloride (Cl) Molybdenum (Mo) Nickel (Ni)
The Elements Elements Ionic forms Soil mobility Plant mobility N NH + 4 Immobile Immobile NO - 3 Mobile Mobile P HPO 2-4, H 2 PO - 4 Very immobile Mobile K K + Immobile Mobile Ca Ca ++ Immobile Very immobile Mg Mg + Immobile Mobile Cu Cu 2+ Very immobile Immobile Fe Fe 3+, Fe 2+ Very immobile Immobile Mn Mn 2+ Very immobile Immobile Zn Zn 2+ Very immobile Immobile B H 3 BO 3 Mobile Very immobile
Elements of Cranberry Fertilizers Macro Micro Nitrogen (N) Phosphorus (P) Potassium (K) Sulfur (S) Calcium (Ca) Magnesium (Mg) Iron (Fe) Copper (Cu) Zinc (Zn) Managanese (Mn) Boron (B) Chloride (Cl)
Know your soil! Nitrogen
Nitrogen Cranberries only use ammonium (NH 4+ ) Actual crop utilization is between 15 30 lbs/a per year Recommended fertilizer rates 0 60 lbs/a per year Key timings bloom, fruit set, bud set Tissue test only no soil test
Nitrogen Nos! Do not apply nitrate (NO 3- ) Do not apply N late in the season Too much N early can lead to vegetative growth Yellow plants may or may not be low N N is not the only element cranberries need
Looks can be Deceiving
Phosphorus Is easily tied up by Fe and Ca Is associated with surface water pollution Energy relations in the plant Fertilizer P vs actual P* 45 lbs/a yearly After frost & at least 1 ½ month preharvest *fertilizer P *0.43 = actual P
Phosphorus NO soil test method works for P
Potassium A cation Gatoraid for plants Fertilizer K vs actual K 60-120 lbs/a yearly *fertilizer k *0.82 = actual K
Potassium A cation Gatoraid for plants Fertilizer K vs actual K 60-120 lbs/a yearly Does NOT control overgrowth Does NOT accelerate dormancy Does NOT affect fruit color or Brix
N-P-K Relatively high annual fertilizer needs Granular fertilizer preference Fertilizer form makes a difference!
N-P-K According to Joan MAP (11-52-0) Rock Phosphate Urea (45-0-0) Ammonium Sulfate (21-0-0) Anything with nitrate Potassium Sulfate (0-0-50) Potassium Chloride (0-0-60)
A Few Other Granular Fertilizer Facts Super and Triple Super Phosphates Sul-Po-Mag (K Mag, 0-0-22) Slow Release Materials (Osmocote, Polymer coated)
The Other Macros Sulfur Calcium Magnesium
The Other Macros Sulfur S containing fertilizers Calcium Cranberries have a relatively low Ca requirement Ca can increase soil ph Magnesium Rarely needed in cranberry
The Micros Boron Copper Zinc
The Micros Boron Pollen tube germination Copper Enzymes Zinc Enzymes and energy
Boron SoluBor, CaB Copper Chelates or Sulfates Fungicides Zinc Chelates or Sufates Fungicides The Micros 1 5 lbs/a (kg/ha) per app, granular or foliar
Tissue Nutrient Standards http://www.prosser.wsu.edu/faculty/davenport.htm
Soil Test Results Organic Matter CEC ph Nitrate Phosphorus
SOIL STANDARDS (ppm) Ammonium acetate extraction Deficient Normal Excess Element below above Potassium (K) 10 10-40 50 Calcium (Ca) 20 20-80 90 Magnesium (Mg) 10 10-25 25 ph 4.0-5.0 Base saturation: Ca should roughly equal the sum of K and Mg. Base saturation is the proportion of the various positive cations in the soil. In acid soils 45-70% should consist of hydrogen ions (these replace much of the Ca that would be found in higher ph soils) Cation Exchange Capacity (CEC): If CEC is low (<10), base saturation proportions are important. If CEC is high and all cations are in the normal range, the proportions in the base saturation are less critical. http://www.umass.edu/cranberry/downloads/chartbooks/2009/nutrition2009.pdf
Soil and Tissue Test Matrix Soil Test High Tissue Test Low Soil Test High Tissue Test High Soil Test Low Tissue Test Low Soil Test Low Tissue Test High
Soil and Tissue Test Matrix Soil Test High Tissue Test Low Root or Water Problem Soil Test High Tissue Test High Too much nutrient hold back! Soil Test Low Tissue Test Low Not enough nutrient add some! Soil Test Low Tissue Test High Contamination?
Based on Tissue Tests If low, add more If high, cut back Norms N 0-60 P 45 K 60-120
The Elements Elements Ionic forms Soil mobility Plant mobility N NH + 4 Immobile Immobile NO - 3 Mobile Mobile P HPO 2-4, H 2 PO - 4 Very immobile Mobile K K + Immobile Mobile Ca Ca ++ Immobile Very immobile Mg Mg + Immobile Mobile Cu Cu 2+ Very immobile Immobile Fe Fe 3+, Fe 2+ Very immobile Immobile Mn Mn 2+ Very immobile Immobile Zn Zn 2+ Very immobile Immobile B H 3 BO 3 Mobile Very immobile
Foliar Dos and Do Nots Quick Fix N P Boron K Micros in season Micros long term These are fertilizers, not fungicides!
Fertilizing Cranberry Know your soil Know your plants Yield history Balanced amounts Avoid drastic changes Avoid fad material
Soil and Tissue Testing Don ts Samples throughout the growing season Uncalibrated test procedures Impact of foliar sprays Under or over compensating with fertilizer
Something Looks Wrong Many potential causes Nutrition is one Not always easy to detect Not always easy to eliminate Trained eyes
Trouble Shooting Both soil and tissue Good and Bad areas Any time of year Same practices regarding bags and material
Nutrient Management Golden Rules Soil and Tissue Sampling is for planning next season Fertilizer at the wrong time can be worse than no fertilizer at all If it sounds too good to be true, it is Show me the data Water and Nutrient Management are inextricably linked