woodsmaneh!
Well-Known Member
[FONT="]OK I'll give in at 6.5 because it's OK for dirt, and lots of supporting references, but it does depend on what your trying to feed your plant as pointed out below. I posted thepH info first but the rest is intresting also, for a text book.
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[/FONT][FONT="]The pH determines solubility in the soil[/FONT][FONT="]
[/FONT][FONT="]1)[/FONT][FONT="] more available at low pH (below 5.5), and less available at high pH. [/FONT][FONT="]
[/FONT][FONT="] Fe, Zn, Cu, Mn, B [/FONT][FONT="]
[/FONT][FONT="]2) more available at high pH (above 6.5), and less available at low pH.[/FONT][FONT="]
[/FONT][FONT="] N, K, Mg, Ca, S, Mo [/FONT][FONT="]
[/FONT][FONT="]3)[/FONT][FONT="] more available at intermediate pH (6-7) [/FONT][FONT="]
[/FONT][FONT="] P [/FONT]
[FONT="]Ideal pH[/FONT][FONT="]
[/FONT][FONT="]slightly acid:[/FONT][FONT="]
[/FONT][FONT="]a)[/FONT][FONT="] around 6.5 for field soil [/FONT][FONT="]
[/FONT][FONT="]b)[/FONT][FONT="] around 5.5-6.0 for artificial growing media made with peat moss or composted bark[/FONT]
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[FONT="]ESSENTIAL ELEMENTS, MOBILITY AND pH EFFECT[/FONT]
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[FONT="]ESSENTIAL ELEMENTS, MOBILITY AND pH EFFECT[/FONT]
[/FONT][FONT="] of its life cycle, and which cannot be substituted for by other chemical[/FONT][FONT="]
[/FONT][FONT="] compounds.[/FONT]
[FONT="]17 ELEMENTS ARE REQUIRED BY PLANTS[/FONT][FONT="]
[/FONT][FONT="] 3 supplied naturally by air and water - comprise the bulk of the plant [/FONT][FONT="]
[/FONT][FONT="] C, H, 0 [/FONT][FONT="]
[/FONT][FONT="] 6 macronutrients[/FONT][FONT="] - required at 0.1 to 6% of the dry weight of plants [/FONT][FONT="]
[/FONT][FONT="] N, P, K, S, Ca, Mg [/FONT][FONT="]
[/FONT][FONT="] 8 micronutrients[/FONT][FONT="]- required at 1 to 300 ppm of the dry weight of plants [/FONT][FONT="]
[/FONT][FONT="] Fe, Zn, Cu, Mo, B, Mn, Cl, Ni [/FONT][FONT="]
[/FONT][FONT="] Cl and Ni are ubiquitous - hence, will not be addressed in detail [/FONT]
[FONT="]The essential elements can be easily remembered by a catch phrase such as [/FONT][FONT="]
[/FONT][FONT="]C[/FONT][FONT="]. HOPKiNS CaFe, CuB, Mn, C.l. MoNiZnsky, Mgr[/FONT][FONT="]
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[FONT="]NUTRIENT MOBILITY[/FONT][FONT="]
[/FONT][FONT="]Two directions of movement in plants[/FONT][FONT="]
[/FONT][FONT="]1)[/FONT][FONT="] acropetal[/FONT][FONT="] - means towards the apex; transport up the in xylem [/FONT][FONT="]
[/FONT][FONT="]2)[/FONT][FONT="] basipetal [/FONT][FONT="]- means towards the base; transport down in the phloem [/FONT]
[FONT="]Two classifications of nutrient mobility [/FONT][FONT="]
[/FONT][FONT="]1)[/FONT][FONT="] mobile [/FONT][FONT="]- moves both up and down the plant by both acropetal and basipetal transport (in both [/FONT][FONT="]
[/FONT][FONT="] the xylem and the phloem). [/FONT][FONT="]
[/FONT][FONT="] Deficiency appears on older leaves first. [/FONT][FONT="]
[/FONT][FONT="] N, P, K, Mg, S [/FONT][FONT="]
[/FONT][FONT="]2)[/FONT][FONT="] immobile[/FONT][FONT="]- moves up the plant by only acropetal (in the xylem) transport [/FONT][FONT="]
[/FONT][FONT="] Deficiency appears on new leaves first. [/FONT][FONT="]
[/FONT][FONT="] Ca, Fe, Zn, Mo, B, Cu, Mn[/FONT][FONT="]
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[FONT="]EFFECT OF pH[/FONT][FONT="]
[/FONT][FONT="]The pH determines solubility in the soil[/FONT][FONT="]
[/FONT][FONT="]1)[/FONT][FONT="] more available at low pH (below 5.5), and less available at high pH. [/FONT][FONT="]
[/FONT][FONT="] Fe, Zn, Cu, Mn, B [/FONT][FONT="]
[/FONT][FONT="]2) more available at high pH (above 6.5), and less available at low pH.[/FONT][FONT="]
[/FONT][FONT="] N, K, Mg, Ca, S, Mo [/FONT][FONT="]
[/FONT][FONT="]3)[/FONT][FONT="] more available at intermediate pH (6-7) [/FONT][FONT="]
[/FONT][FONT="] P [/FONT]
[FONT="]Ideal pH[/FONT][FONT="]
[/FONT][FONT="]slightly acid:[/FONT][FONT="]
[/FONT][FONT="]a)[/FONT][FONT="] around 6.5 for field soil [/FONT][FONT="]
[/FONT][FONT="]b)[/FONT][FONT="] around 5.5-6.0 for artificial growing media made with peat moss or composted bark[/FONT]
[FONT="]FERTILIZER ANALYSIS AND RATIO[/FONT]
[/FONT][FONT="]analysis[/FONT][FONT="] - sequence of 3 numbers on the fertilizer label that gives the percent composition of [/FONT][FONT="]
[/FONT][FONT="] N-P205-K20 in a fertilizer; required by law to be on the label of every fertilizer sold. [/FONT]
[FONT="]Example: 8-8-8 means the fertilizer contains:[/FONT][FONT="]
[/FONT][FONT="]8% N [/FONT][FONT="]
[/FONT][FONT="]8% P205 [/FONT][FONT="]
[/FONT][FONT="]8% [/FONT][FONT="]K20 [/FONT][FONT="]
[/FONT][FONT="]24% total nutrient content [/FONT]
[FONT="] Buy fertilizers by price per pound of fertilizer, not price per bag.[/FONT]
[FONT="]100 lb. of 8-8-8 @ $4.99
[/FONT][FONT="]100 lb. @ 24% = 24 lb. of nutrients
@ $4.99 = 20.8 cents per lb[/FONT]
[/FONT][FONT="]100 lb. @ 24% = 24 lb. of nutrients
@ $4.99 = 20.8 cents per lb[/FONT]
[FONT="]100 lb. of 13-13-13 @ $5.99
[/FONT][FONT="]100 lb @ 39% = 39 lb. of nutrients
@ $5.99 = 15.3 cents per lb.[/FONT]
[/FONT][FONT="]100 lb @ 39% = 39 lb. of nutrients
@ $5.99 = 15.3 cents per lb.[/FONT]
[/FONT][FONT="]FERTILIZER RATIO[/FONT][FONT="]
[/FONT][FONT="]ratio[/FONT][FONT="] - the relative proportion of N to P205 to K20 in a fertilizer.[/FONT]
[FONT="]Analysis
[/FONT][FONT="]8-8-8
20-20-20
10-20-10
18-6-12[/FONT]
[/FONT][FONT="]8-8-8
20-20-20
10-20-10
18-6-12[/FONT]
[FONT="]Ratio
[/FONT][FONT="]1-1-1
1-1-1
1-2-1
3-1-2[/FONT]
[/FONT][FONT="]1-1-1
1-1-1
1-2-1
3-1-2[/FONT]
[/FONT][FONT="]USING FERTILIZER RATIOS TO MANIPULATE GROWTH[/FONT][FONT="]
[/FONT][FONT="]a)[/FONT][FONT="] to favor vegetative growth [/FONT]
- [FONT="]use a high N, low P and K fertilizer[/FONT]
- [FONT="]for example, use a 2-1-1 or 3-1-1 ratio fertilizer (higher 1st number) [/FONT]
- [FONT="]use a low N, high P and/or K fertilizer[/FONT]
- [FONT="]for example, use a 1-2-2 or 1-3-2 ratio fertilizer (higher 2nd and/or 3rd number) [/FONT]
[FONT="]FUNCTION OF NUTRIENTS[/FONT]
[FONT="] Symbol[/FONT]
[FONT="]Function[/FONT]
[FONT="]nitrogen[/FONT]
[FONT="]N[/FONT]
[/FONT][FONT="] nucleic acids (RNA and DNA); some auxins and cytokinins. [/FONT]
[FONT="]phosphorus[/FONT]
[FONT="]P[/FONT]
[/FONT][FONT="] NADP; nucleic acids (DNA and RNA); and phospholipids. [/FONT]
[FONT="]potassium[/FONT]
[FONT="]K[/FONT]
[/FONT][FONT="]2)[/FONT][FONT="] Involved in maintaining proper water balance [/FONT][FONT="]
[/FONT][FONT="]3)[/FONT][FONT="] Needed for photosynthesis. [/FONT]
[FONT="]magnesium[/FONT]
[FONT="]Mg[/FONT]
[/FONT][FONT="]2)[/FONT][FONT="] Activates many enzymes. [/FONT]
[FONT="]calcium[/FONT]
[FONT="]Ca[/FONT]
[/FONT][FONT="]2)[/FONT][FONT="] Required for normal cell division and meristem growth. [/FONT][FONT="]
[/FONT][FONT="]3)[/FONT][FONT="] Stabilizes membranes[/FONT]
[FONT="]sulfur[/FONT]
[FONT="]S[/FONT]
cysteine).[/FONT]
[FONT="]iron[/FONT]
[FONT="]Fe[/FONT]
[/FONT][FONT="]2)[/FONT][FONT="] Component of many enzymes and carriers, especially those of [/FONT][FONT="]
[/FONT][FONT="] electron transport chain.[/FONT]
[FONT="]zinc[/FONT]
[FONT="]Zn[/FONT]
[FONT="]manganese[/FONT]
[FONT="]Mn[/FONT]
[/FONT][FONT="]2)[/FONT][FONT="] Activates many enzymes.[/FONT]
[FONT="]copper[/FONT]
[FONT="]Cu[/FONT]
[/FONT][FONT="]2)[/FONT][FONT="] Component of many enzymes and carriers, especially those of [/FONT][FONT="]
[/FONT][FONT="] electron transport chain.[/FONT]
[FONT="]boron[/FONT]
[FONT="]B[/FONT]
[/FONT][FONT="]2)[/FONT][FONT="] Involved in translocation of carbohydrates and hormones. [/FONT]
[FONT="]molybdenum[/FONT]
[FONT="]Mo[/FONT]
[/FONT][FONT="]2)[/FONT][FONT="] Component of enzymes in nitrogen fixation (N gas to ammonia)[/FONT]
[FONT="]chlorine[/FONT]
[FONT="]Cl[/FONT]
[/FONT][FONT="]2)[/FONT][FONT="] Stomatal functioning [/FONT]
[FONT="]nickel[/FONT]
[FONT="]Ni[/FONT]
down urea)[/FONT]
[FONT="]TISSUE CONCENTRATION, DEFICIENCY SYMPTOMS AND FERTILIZER SOURCES[/FONT]
[FONT="]Tissue Concentration[/FONT]
[FONT="]Characteristic Deficiency Symptom[/FONT][FONT="]*[/FONT]
[FONT="]
[/FONT][FONT="]MACRONUTRIENTS[/FONT]
[/FONT][FONT="]MACRONUTRIENTS[/FONT]
[FONT="]N[/FONT]
[FONT="]2-6%[/FONT]
[FONT="]NH4 nitrate, sulfate, phosphate; [/FONT][FONT="]
[/FONT][FONT="]K, Na, or Ca nitrate; urea [/FONT]
[FONT="]P[/FONT]
[FONT="]0.2-1.2%[/FONT]
[FONT="]superphosphate; NH4 or K phosphate; phosphoric acid [/FONT]
[FONT="]K[/FONT]
[FONT="]1-6%
(luxury
consumption)[/FONT]
(luxury
consumption)[/FONT]
[FONT="]K nitrate, chloride, phosphate, or sulfate; K frit [/FONT]
[FONT="]Mg[/FONT]
[FONT="] 0.2-1%[/FONT]
[FONT="]dolomite (Ca/Mg carbonate), [/FONT][FONT="]
[/FONT][FONT="]Mg sulfate (Epsom salt)[/FONT]
[FONT="]Ca[/FONT]
[FONT="]0.5-2% [/FONT]
[FONT="]limes (Ca carbonate/hydroxide); [/FONT][FONT="]
[/FONT][FONT="]Ca sulfate (gypsum) or nitrate; [/FONT][FONT="]
[/FONT][FONT="]superphosphate[/FONT]
[FONT="]S[/FONT]
[FONT="]0.3-0.7%[/FONT]
[FONT="]sulfate carriers; elemental S; [/FONT][FONT="]
[/FONT][FONT="]air pollution; superphosphate[/FONT]
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[/FONT][FONT="]MICRONUTRIENTS**[/FONT]
[/FONT][FONT="]MICRONUTRIENTS**[/FONT]
[FONT="]Fe[/FONT]
[FONT="]50-300 ppm[/FONT]
[FONT="]Fe chelate; Fe sulfate; some pesticides [/FONT]
[FONT="]Zn[/FONT]
[FONT="]5-75 ppm[/FONT]
[FONT="]Zn chelate; Zn sulfate; [/FONT][FONT="]
[/FONT][FONT="]some pesticides[/FONT]
[FONT="]Mn[/FONT]
[FONT="]30-300 ppm[/FONT]
[FONT="]Mn chelate; Mn sulfate; [/FONT][FONT="]
[/FONT][FONT="]some pesticides[/FONT]
[FONT="]Cu[/FONT]
[FONT="]5-30 ppm[/FONT]
[FONT="]Cu chelate; Cu sulfate; [/FONT][FONT="]
[/FONT][FONT="]some pesticides[/FONT]
[FONT="]B[/FONT]
[FONT="]30-200 ppm[/FONT]
[FONT="]borax; boric acid[/FONT]
[FONT="]Mo[/FONT]
[FONT="]1 ppm[/FONT]
[FONT="]Na or NH4 molybdate [/FONT]
[FONT="]Cl[/FONT][FONT="] &[/FONT][FONT="]Ni[/FONT]
[FONT="]?[/FONT]
[FONT="]ubiquitous[/FONT]
[FONT="]*chlorosis[/FONT][FONT="] = yellowing; necrosis = browning; interveinal = between the veins [/FONT][FONT="]
[/FONT][FONT="]**micronutrients[/FONT][FONT="] are often applied as a multi-micronutrient mix; ex. STEM, PERK, Micromax[/FONT]
[FONT="]NUTRIENTS WITH SIMILAR DEFICIENCY SYMPTOMS[/FONT]
[FONT="]Nutrients That Cause Interveinal Chlorosis[/FONT]
[FONT="]Deficiency Of[/FONT]
[FONT="]Interveinal Chlorosis Occurs On[/FONT]
[FONT="]With No Necrosis[/FONT]
[FONT="]Plus Necrosis[/FONT]
[FONT="]Young Leaves[/FONT]
[FONT="]Fe[/FONT]
[FONT="]Mn[/FONT]
[FONT="]Old Leaves[/FONT]
[FONT="]Mg[/FONT]
[FONT="]K[/FONT]
[FONT="]Nutrients That Cause Overall Chlorosis[/FONT]
[FONT="]Overall Chlorosis Occurs on[/FONT]
[FONT="]Deficiency Of[/FONT]
[FONT="]Old Leaves[/FONT]
[FONT="]N[/FONT]
[FONT="]New Leaves[/FONT]
[FONT="]Mo[/FONT]
[FONT="]New Leaves, Then Spreading to Old Leaves[/FONT]
[FONT="]S[/FONT]
[FONT="]Nutrients That Effect the Shoot Tip[/FONT]
[FONT="]Various Deficiency Symptoms
on Growing Point, Emerging Leaves or[/FONT][FONT="]Shoot Tip [/FONT]
on Growing Point, Emerging Leaves or[/FONT][FONT="]Shoot Tip [/FONT]
[FONT="]Deficiency Of[/FONT]
[FONT="]Small New Leaves and Rosetted New Growth[/FONT]
[FONT="]Zn[/FONT]
[FONT="]Thick and Brittle New Leaves[/FONT]
[FONT="]B[/FONT]
[FONT="]New Leaves Distorted and Necrotic[/FONT]
[FONT="]Ca[/FONT]
[FONT="]Vague Symptoms: New Leaves Small, Wilted, Translucent or Necrotic[/FONT]
[FONT="]Cu[/FONT]
[FONT="]NITROGEN CYCLE[/FONT]
[FONT="]
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[/FONT][FONT="]1) [/FONT][FONT="]leaching[/FONT][FONT="] (especially nitrate which is negatively charged)[/FONT][FONT="]
[/FONT][FONT="]2)[/FONT][FONT="]plant absorption[/FONT][FONT="]
[/FONT][FONT="]3)[/FONT][FONT="]microorganisms consume[/FONT][FONT="] (see C:N ratio next page)[/FONT][FONT="]
[/FONT][FONT="]4)[/FONT][FONT="] denitrification[/FONT]
[FONT="]NITROGEN CONVERSIONS[/FONT]
[/FONT][FONT="]mineralization [/FONT][FONT="]or[/FONT][FONT="] ammonification [/FONT][FONT="]-the conversion of organic nitrogen (in the -NH2 form) to[/FONT][FONT="]
[/FONT][FONT="] inorganic nitrogen (in the NH4 form).[/FONT][FONT="]
[/FONT][FONT="] - the speed of conversion depends on the C:N ratio (see below).[/FONT][FONT="]
[/FONT][FONT="]nitrification [/FONT][FONT="]- [/FONT][FONT="]a two step process converting ammonium to nitrite, then nitrite to nitrate.[/FONT][FONT="]
[/FONT][FONT="] - the soil bacterium Nitrosomonas converts ammonium to nitrite[/FONT][FONT="]
[/FONT][FONT="] - the soil bacterium Nitrobacter converts nitrite to nitrate[/FONT][FONT="]
[/FONT][FONT="] - this occurs very quickly so little ammonium (which can be toxic if high) and[/FONT][FONT="]
[/FONT][FONT="] virtually no nitrite (which is highly toxic) accumulates in the soil.[/FONT][FONT="]
[/FONT][FONT="]denitrification[/FONT][FONT="] - the conversion of nitrate in the soil to gaseous nitrogen that escapes into the[/FONT][FONT="]
[/FONT][FONT="] atmosphere.[/FONT]
[FONT="]nitrogen fixation[/FONT][FONT="] - the conversion of gaseous nitrogen to ammonia.[/FONT][FONT="]
[/FONT][FONT="] - only nitrogen fixing microorganisms can cause nitrogen fixation; [/FONT][FONT="]
[/FONT][FONT="] some form symbiotic relationships with plants (see table below)[/FONT][FONT="]
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[FONT="]CARBON:NITROGEN (C:N) RATIOS IN ORGANIC MATTER[/FONT][FONT="]
[/FONT][FONT="]C:N[/FONT][FONT="] Ratio - proportion of carbon to nitrogen present in organic matter. [/FONT][FONT="]
[/FONT][FONT="]a)[/FONT][FONT="] high C:N ratio- wood, sawdust, uncomposted bark [/FONT][FONT="]
[/FONT][FONT="] - microbes use up all nitrogen in organic matter when consuming carbon, [/FONT][FONT="]
[/FONT][FONT="] - then the microbes use up the nitrogen in the soil [/FONT][FONT="]
[/FONT][FONT="]b)[/FONT][FONT="] low C:N ratio - manure, bone meal, fish emulsion, organic fertilizers [/FONT][FONT="]
[/FONT][FONT="] - microbes consume carbon, [/FONT][FONT="]
[/FONT][FONT="] - then release excess nitrogen from the organic matter into the soil [/FONT][FONT="]
[/FONT][FONT="] - thus, low C:N organic matter acts as an organic nitrogen fertilizer[/FONT][FONT="]
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[FONT="]MICROORGANISMS THAT CAN FIX NITROGEN[/FONT]
[FONT="]Type Microorganism[/FONT]
[FONT="]Nitrogen-Fixing
Microorganism[/FONT]
Microorganism[/FONT]
[FONT="]Forms Symbiotic
Relationship With[/FONT]
Relationship With[/FONT]
[FONT="]Rhizobium[/FONT]
[FONT="]Legumes
(soybean, clover, mesquite)[/FONT]
(soybean, clover, mesquite)[/FONT]
[FONT="]Azotobacter
Clostridium[/FONT]
Clostridium[/FONT]
[FONT="]free living only[/FONT]
[FONT="]some Actinomycetes[/FONT]
[FONT="]Some woody plants,
(Alnus and Elaeagnus)[/FONT]
(Alnus and Elaeagnus)[/FONT]
4)[/FONT][FONT="] Blue-green algae[/FONT][FONT="]
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[FONT="]Anabaena[/FONT]
[FONT="]Azolla[/FONT][FONT="] and Cycads
(can also be free living)[/FONT]
(can also be free living)[/FONT]