Advanced Liner Nutrient Management Topics What do we start with Nutrition under mist Finishing the crop Identifying and correcting problems Bill Argo, Ph.D. Blackmore Company Tissue Nutrient Levels Survey Details: Tissue levels above or below the "low" or "high" levels do not necessarily indicate a problem. Samples were entire unrooted cuttings (including stems and leaves) from healthy crops 10% of samples were below the "low" level and 10% of samples were above the "high" level. Only species with at least 10 samples are included. The more samples and number of locations increases the confidence that the survey represents typical numbers for the species. Published as: Santos, K.M., P.R. Fisher, and W.R. Argo. 2011. Survey of tissue nutrient levels in vegetative cuttings. Comm. Soil Sci. Pant Analysis. 42:669-693. Petunia Nutrient Low High Mean N % 4.5 6.9 5.7 P % 0.4 0.7 0.6 K % 4.1 6.0 5.0 Ca % 0.7 1.8 1.1 Mg % 0.3 0.8 0.5 S % 0.4 1.1 0.8 Fe ppm 61 183 110 Mn ppm 50 124 81 Zn ppm 29 81 50 Cu ppm 4 16 10 B ppm 25 64 41 Mo ppm 1.8 11.5 5.8 Al ppm 0 185 82 Samples 291 Locations 10 Nutrition under Mist (Stages 0 2): Initial sticking, callus, and root initials. trogen % Nit Mist Fertigation 7 6 5 4 3 2 1 0 0 7 14 21 Days after Sticking Petunia 1
Stock Effects on Initial Nutrient Levels with Petunias Stock Treatment Initial Nutrient Concentration N P K High (200 mg N L -1 ) 5.6 0.75 5.1 Moderate (100 mg N L -1 ) 4.9 0.50 4.3 Low (50 mg N L -1 ) 4.7 0.39 3.7 Control (0 mg N L -1 ) 3.4 0.24 2.5 en % Nitroge 6.0 5.5 5.0 4.5 40 4.0 3.5 3.0 2.5 2.0 1.5 1.0 Initial Tissue N Affects Likelihood of Deficiency during Propagation 0 2 4 6 8 10 12 14 16 18 Time (days) en % Nitroge 5.5 5.0 4.5 40 Initial Tissue N Affects Likelihood of Deficiency during Propagation 6.0 6.9% N (High tissue level) 5.7% N (Mean tissue level) 4.0 4.5% N (Low tissue level) 3.5 3.0 2.5 2.0 1.5 1.0 0 2 4 6 8 10 12 14 16 18 Time (days) Petunia Nutrient Low High Mean Acceptable range N % 4.5 6.9 5.7 3.5-5.5 P % 0.4 0.7 0.6 0.3-1.0 K % 4.1 6.0 5.0 2.0 8.0 Ca % 0.7 1.8 1.1 0.8 1.5 Mg % 0.3 0.8 0.5 0.2 1.5 S % 0.4 1.1 0.8 0.2 0.5 Fe ppm 61 183 110 60 200 Mn ppm 50 124 81 50 200 Zn ppm 29 81 50 30 150 Cu ppm 4 16 10 5 25 B ppm 25 64 41 30 125 Mo ppm 1.8 11.5 5.8 0.5 10 Al ppm 0 185 82 Samples 291 Locations 10 Petunia % Nitrogen Does adding fertilizer in the mist help? Mist Fertigation 7 100 ppm N 0 ppm N 6 5 4 3 2 1 0 0 7 14 21 Days after Sticking A B Treatments were varied in intervals of two (A & B) fertilizer solutions 75 (NO 3 -N) 25 (NH 4 -N) 12 P 83 K 20 Ca 10 Mg 21.7 S Fe Fe 1 Mn Mn 1 Zn Zn 0.5 Cu Cu 0.5 B 0.2 Mo Treatment Week 1 Week 2 Week 3 1 A A A 2 A A B 3 A B B 4 A B A 5 B B B 6 B B A 7 B A A 8 B A B A = Complete fertilizer solution B = Micronutrient fertilizer solution 2
Mist Fertigation Mist Fertigation 7 6 100 ppm N 0 ppm N 0 ppm N Constant 100 ppm N Constant 5 rogen % Nitr 4 3 2 1 0 0 7 14 21 Days after Sticking 0 ppm N 100 ppm N Extended N applications can reduce rooting and increase shoot growth Extreme deficiency also reduces growth and plant health Is it better to foliar feed, or supply nutrients to the roots? Response by Cutting Clear Above Fertilizer Above Clear Below Fertilizer Below Clear Below Fertilizer Below Species Response to Fertilizer in Mist during week 1 Positive Neutral Negative Petunia Osteospermum Helichrysum Calibrachoa Vinca Lavender Coleus Poinsettia Phlox Spathyphyllum Scaevola Anthurium Dahlia Guzmania Bacopa Ferns Lantana Fertilizer application on Poinsettias during propagation Avoid P in foliar fertilizer Rinse foliage after fertilizer application Photos by Harvey Lang, Syngenta 3
What happens to Starter Fertilizers under mist? Leaching, ph, and EC under mist Finishing phase (Stages 3 & 4): Root and shoot growth through to shippable plug Applying Soluble Nutrients Plant growth is based on the amount of fertilizer you apply. The amount of fertilizer you apply is based on: 1) Concentration 2) Volume applied 3) Frequency What are my fertilizer sources? Water-soluble Fertilizer Media Irrigation water Grower #1 Petunia Liner crop - Use 13-2-13 fertilizer at 125 ppm N Preplant Fertilizers Nutrient Lime Reactive Residual Peat/perlite mix with dolomitic lime but no starter - Peat/perlite mix with dolomitic lime, but no starter - Pure water source (0.05 ms/cm) Other 4
Water-soluble fertilizer Irrigation water Lime Preplant Media Other N P K Ca Mg S Grower #2 Petunia Liner crop - Use 13-2-13 fertilizer at 125 ppm N - Peat/perlite mix with dolomitic lime and starter - Water source with high alkalinity, calcium, and magnesium, and sulfur (0.5 ms/cm) - Uses sulfuric acid (93%) for acidification - Low rate of a 90-day 19-6-12 resin-coated fertilizer (2 lbs./yd 3 ) added to the mix Water-soluble fertilizer Irrigation water Lime Preplant Media Other N P K Ca Mg S Fate of applied to a crop 1)Remains in the pot 2)Plant uptake 3)Leaching How much fertilizer does it take to grow a plant? 5
Fate of applied to a crop Leaching 1)Remains in the pot 2)Plant uptake 3)Leaching Leaching Fraction (LF) Leaching Fraction is a relative term. Difficult to predict how leaching fraction will influence nutrient removal. Container Capacities Leached (CCL) Container Capacities leached is a consistent term based on the water-holding capacity of the media and pot. Leaching Leaching Effects on WSF Rates Leaching Fraction (LF) Container Capacities Leached (CCL) Volume leached Volume leached = = LF CCL Volume applied Container capacity of the pot 5 fl.oz 5 fl.oz = 25% 20 fl.oz. 20 fl.oz. = 25% 1 fl.oz 1 fl.oz = 25% 4 fl.oz. 20 fl.oz. = 5% Yelanich and Biernbaum, 1993 The more you leach (withdraw), the more fertilizer you must apply (deposit) conductivity er 16 wks Media-Electroc (ms/cm) afte 10 8 6 4 2 0 100 ppm N 200 ppm N 400 ppm N Optimum EC range 0% 15% 35% 55% Leaching fraction (%) with each fertigation Yelanich and Biernbaum (1993) Yelanich and Biernbaum (1994) 6
As leaching rates increase, the fertilizer concentration applied must also increase to compensate for the loss of nutrients. As leaching rates decrease, the fertilizer concentration applied must also decrease because nutrients are no longer being lost from the pot. 2008 Survey of water used in cutting production CC Leached per tray (4 week avg.) Grower A 0.8 Grower B 4.7 Grower C 1.3 Grower D 0.4 Grower E 1.0 Grower F 1.3 Grower G 2.2 Grower H 2.0 Average 1.7 What fertilizer concentration should I use? Santos, Fisher, and Argo, 2008 Typical in-house media ph and EC levels 2:1 Method Saturated media extract method Pour-thru Method Squeeze Method No fertility 0 0.25 0 to 0.75 0 to 1.0 0 to 1.0 Low fertility 0.30 to 0.75 1.0 to 2.0 1.0 to 2.5 1.0 to 2.5 Acceptable range 0.30 to 1.50 1.0 to 3.5 1.0 to 6.0 1.0 to 5.0 High fertility 0.75 to 1.50 2.5 to 3.5 4.0 to 6.0 2.5 to 5.0 Potential root damage >2.50 > 5.0 > 8.0 > 8.0 7
Phosphorus Concentrations in common water-soluble Phosphorus Concentrations (ppm P) 50 ppm N 100 ppm N 150 ppm N 200 ppm N 14-0-14 0 0 0 0 13-2-13 3 6 9 13 12-4-12 7 14 21 28 14-4-14 6 12 18 24 17-5-17 6 12 18 25 20-10-20 10 21 32 43 20-20-20 21 43 63 86 9-45-15 107 214 321 430 Nutrient Concentration (at 200 ppm N) General Purpose 20-20-20, 15-16-17, 21-7-7 Fe Mn Zn Cu B Mo 0.5 0.1 0.1 0.05 0.05 0.03 Peat-lite Formula 20-10-20, 17-5-17, 13-2-13 Fe Mn Zn Cu B Mo 1.0 0.4 0.4 0.3 0.2 0.08 General group ph Problem: Usually none Ideal ph 5.8 to 6.4 What are acceptable ph ranges for plants? Petunia group ph Problem: Iron-inefficient, prone to iron deficiency at high ph, especially at low EC). Geranium group ph Problem: iron-efficient, prone to iron/ manganese toxicity at low ph, especially at high EC 5.4 to 6.2 6.0 to 6.6 Iron deficiency problems Can be used to modify these acceptable ph ranges? 4.4 4.7 5.1 6.0 7.0 Media ph 8
Nutrient Concentration (at 200 ppm N) Media ph = 7.0 General Purpose 20-20-20, 15-16-17, 21-7-7 Fe Mn Zn Cu B Mo 0.5 0.1 0.1 0.05 0.05 0.03 Peat-lite Formula 20-10-20, 17-5-17, 13-2-13 Fe Mn Zn Cu B Mo 1.0 0.4 0.4 0.3 0.2 0.08 0.5 ppm 1.0 ppm 2.0 ppm FeEDTA 100 ppm N 200 ppm N 400 ppm N Peat-lite 200 ppm N 400 ppm N 800 ppm N G.P. Forms of Iron Form % iron Other names Iron sulfate 20.5% Fe Ferrous sulfate ph = 5.1 Iron-EDDHA Applied Fe (ppm) 0.25 0.5 1.0 2.0 Iron EDTA 13% Fe Sequestrene Fe Dissolzine EFe13 Iron-EDTA Iron DTPA Iron EDDHA 10-11% Fe 6% Fe Sequestrene 330 Sprint 330 Dissolzine DFe11 Sequestrene 138 Sprint 138 Dissolzine QFe6 Iron sulfate ph = 6.4 Applied Fe (ppm) ph = 6.9 Applied Fe (ppm) 0.25 0.5 1.0 2.0 0.25 0.5 1.0 2.0 Iron-EDDHA Iron-EDDHA Iron-EDTA Iron-EDTA Iron sulfate Iron sulfate 9
Calibrachoa Trailing White at ph 6.6 Control 0.5 1.0 2.0 4.0 ppm Fe-EDDHA Fe-EDTA FeSO 4 ilizer Concentration Applied Ferti 300 ppm N 1.50 ppm Fe 225 ppm N 1.11 ppm Fe 150 ppm N 0.75 ppm Fe 75 ppm N 0.38 ppm Fe 3.8 4.3 4.8 5.5 Root-media ph Holding Liners What about your customers? Using Nutrient Deficiency for Height Control Nitrogen Deficiency Phosphorus Deficiency Phosphorus Concentrations in common water-soluble Phosphorus Concentrations (ppm P) 50 ppm N 100 ppm N 150 ppm N 200 ppm N 14-0-14 0 0 0 0 13-2-13 3 6 9 13 12-4-12 7 14 21 28 14-4-14 6 12 18 24 17-5-17 6 12 18 25 20-10-20 10 21 32 43 20-20-20 21 43 63 86 trogen % Nit 7 6 5 4 3 2 1 0 0 7 14 21 Days after Sticking 9-45-15 107 214 321 430 10
Fixing i Problems Correcting nutritional problems!!a Disclaimer!! The following recommendations for raising or lowering media-ph are for crops already under stress. Prevention of ph problems is better than relying on a cure. Phytotoxicity or staining is very likely with these chemicals, and applications should be tested on a small number of plants before applying to the entire crop. Necrotic tissue will NOT recover, and the goal is to produce new healthy foliage that will cover damage. It is up to you to balance the risk of applying caustic chemicals to yourself or to the crop against the potential for damage caused by high or low medium-ph. General Rule: The concentration used for a 1-time corrective application should be 5x to 10x the maintenance concentration Maintenance 5x rate 10x rate Nitrogen 50 ppm N 250 ppm N 500 ppm N Phosphorus 8 ppm P 40 ppm P 80 ppm P Magnesium 25 ppm Mg 125 ppm Mg 250 ppm Mg Iron 1.0 ppm Fe 5 ppm Fe 10 ppm Fe Boron 0.25 ppm B 1.25 ppm B 2.5 ppm B Correcting high media-ph induced iron deficiency Actions needed when media-ph is too high: 1. Try to lower the media-ph with fertilizer and low alkalinity Ammonium fertilizer combined with low alkalinity (may require water acidification). e.g. 21-7 7 (all ammonium + urea) 9-45 15 (all ammonium) Correcting high media-ph Actions needed when media-ph is too high: 1. Try to lower the media-ph with fertilizer and low alkalinity 2. Correct micronutrient deficiencies Masking the symptoms of high ph with micronutrient applications can be effective. If EC is not already high, 2 applications 300 ppm N. Otherwise if EC is high, leach with clear water first, then apply. 11
Mask symptoms of high-ph with iron Mask symptoms of high-ph with iron ppm iron 20 40 80 Iron-EDDHA Iron-DTPA Media ph = 7.3 37.5 ppm Fe Drench Control (water) Calibrachoa 7/5/01 (10 days after single drench application, ph 7.0) Correcting low media-ph induced iron/manganese toxicity Flowable lime and potassium bicarbonate are the best options to raise ph quickly. Nitrate, calcium hydroxide solution, potassium hydroxide, top dressing lime are other options. Choosing between flowable lime and potassium bicarbonate Potassium bicarbonate for flood floors, low-volume drippers, hard-to-reach corners 2 lbs./100 gals (2.4 grams/liter) Otherwise flowable lime - more reliable and stable effect on media-ph, without increasing media-ec. 4 qts./100 gallons (= 10 ml/liter = 1:100) Potassium bicarbonate Flowable lime Test after 5 days, and reapply if ph is not at the target level. Tips for Potassium bicarbonate Tips for Flowable Lime Can be delivered through emitters or on flood floors. Apply in cool weather so that salt does not dry quickly on foliage. Apply in cool weather so that lime does not dry quickly on foliage. Immediately rinse foliage after application using fine spray. One day after application, apply a basic fertilizer (e.g. 13-2-13) with moderate leaching to wash out salts and to reestablish nutrient balance. Leaf distortion from potassium bicarbonate residue Immediately rinse foliage after application using fine spray. Immediately clean equipment. Flowable lime residue after washing 12