Dictionary of Terms

Fertilizer labels can be confusing. "Balanced" doesn't mean that nutrient levels are balanced; it just means a fertilizer contains the big three: nitrogen (N), phosphorus (P), and potassium (K). Seeing "organic" on the label won t guarantee that all ingredients are derived from natural animal, plant, or mineral sources

Here's a quick guide to different types of fertilizers. Most fall into more than one of the following categories.

  • Simple fertilizer contains one major nutrient (N, P, or K). ' :
  • Compound fertilizer provides two or more of the major nutrients.
  • quot;Complete" or balanced fertilizer contains N, P, and K (5-10-5 or 5-10-10); may not contain any micro-

nutrients; may be either synthetic or organic.

  • Special-purpose fertilizer is usually a balanced fertilizer, but one that is formulated for particular types of plants rather than for general use. (Bulb fertilizers and formulas for acid-loving plants are examples.)
  • Slow-release fertilizer, also called timed-release fertilizer, is a pelletized form of concentrated, fast-

acting fertilizer treated to make it release nutrients (especially nitrogen) gradually and over a longer period of time. Such formulas won't burn plants or soil organisms. More expensive than ordinary types. Also available as spikes, tablets, and pouches.

  • Liquid fertilizer is a powder or concentrated liquid that's diluted with water and then poured onto soil. Some types are designed to supply nutrients through plant leaves (see "Foliar Feeding" on page 115); these are sprayed onto plants. Fast-acting but more expensive than other types; good for short-term treatment of deficiencies caused by soil alkalinity or acidity.
  • Organic fertilizer may not actually refer to nutrients from natural animal, plant, or mineral sources. To chemists — and therefore to the fertilizer industry — "organic" usually refers to any compounds that contain ^bon. "Organic" may also appear on a blended fertilizer that contains some seaweed or other natural source. If m or more of the N-P-K numbers is higher than 10, a fertilizer has probably been boosted with concentrated, synthetic nutrient sources.
  • Natural fertilizer usually indicates nutrients from natural animal, plant or mineral sources. Fertilizer label-N requirements don't give any definition for this term, though. To be sure you know what you re getting, read the ingredient list carefully (and read up on the ingredients later in this chapter).
  • Synthetic fertilizer is one that contains nutnents forme*, by °f Wmm processes or bY processing mined minerals with chemicals such as sulfuric acid. Sometimes called pxuLesses, oi Dy piucc^i h fertilizers are a so made up of chemicals, chemical fertilizers," but that's misleading, because natural fertilizers a


Reading the Fine P

Here's a guide to the fine print on fertilizer labels. Two examples are shown on the next page, since labels vary greatly The label at the top is from a general-purpose organic fertilizer. The label at the bottom (shown in two parts) is a specialized synthetic fertilizer formulated for acid-loving ornamentals. As you'll see from these exam* ;; pies, the following items don't always appear on labels. ^«H^^^^^^H

A Guaranteed analysis. Often referred to as the N-P-K, gives nutrient content as a percentage of total weight (pounds per 100 pounds of fertilizer). It's confusing because the percentages don't refer to the elements by themselves. The nitrogen number (8% in the evergreen fertilizer; 4% in the organic) is straightforward; it gives the total amount of that element. But the second number refers to the percentage of phosphate (P205) available in the first year (4% and 5%, respectively), not the total amount of pure phosphorus (P), which is greater than the listed percentage. The third number refers to potash (K20) soluble (available) the first year (4% and 4%), not total potassium (K). (vSee box at right for conversions.) The nitrogen figure is often broken down to show what forms are present.

B Micronutrients. May be listed on labels of fertilizers that supply them (not required by labeling laws); the "Organic Plant Food" doesn't list them even though the ingredients (poultry manure) will supply some micronutrients.

C Ingredients. Tells the source of each nutrient. Often listed as a breakdown under the guaranteed analysis ("Derivedfrom..."). M j

D Filler. The weight remaining after the total of the N-P-K percentages is subtracted. Substances used as filler help in spreading fertilizer evenly or control the rate of release in slow-release fertilizers. In organic fertilizers, fillers may also supply some organic matter or micronutrients. Often not listed (as on these samples).

E Acid equivalent. The amount of acidity this product will cause in soils, expressed in pounds of limestone. Cottonseed meal and several synthetic fertilizers increase soil acidity. Unless you're trying to lower the pH, you'll theoretically need to add the listed amount of limestone to the same area covered by the entire bag of fertilizer to restore the pH. (But remember, don't add limestone and nitrogen fertilizers at the same time or you'll convert the nitrogen to a form that evaporates.)

F Recommended application rates. These amounts are general suggestions for soils that are already in balance. Different rates are usually given for different types of crops/plants. If a soil test shows one or more major deficiencies, you'll have to correct them before following these recommendations.

G Special instructions. For special-purpose fertilizers, labels usually list which plants or types of they are designed for. and/or special uses such as foliar feeding.

H Warnings. Label may list precautions for handling, use, or disposal. .: jjtt^^^^^H

112 secrets to great soil


Nature's Way

Organic Plant Food

For Flowers, Vegetables A Herbs Steady, Healthy Crowth

This oil organic fertilizer is blended for oil purpose use in flower, vegetable and herb gardens and even landscaped creos.

New Plantings

Prepare garden for planting. Spread 7 lbs. of Oraonic Plant Food per 20 sq. ft. (4 ft. x 5 ft.) evenly over soil surface and m»x into top 3-4 inches thoroughly. Coverage should look like figure at right.

Established Plantings

In spring when new growth starts, apply 5 lbs. per 30 so ft along rows or spread 1/4 cup per 1 sq. ft. oreo under' the hps of plant branches. Repeat application every 4-4 weeks, stopping 4 weeks before frost. Coverage should look like figure at right.



COVERAGE FORI SQ.FT. Estabfehod Plantings

AGWAY Guarantees Satisfaction

If for any reoson you ore not fuJIjf

Cimmy.n] ¿RmsFAivm, satisfied with the performance of this product, we wont to know. Just bring the Hem back to the store and we will exchange it or issue a refund.

Guaranteed Analysis:

2.20% Water Insoluble Nitrogen 1.80% Water Soluble Nitrogen /VfQnuOiC »nOSpnOTO IrOvVsJ 5.00%

Soluble Potash (KoOJ 4.00%

i Primoiy nutrients derived from: Poultry Manure.

COVERAGE FORI SQ.FT. Estabfehod Plantings


How Much to Use

Nutrient recommendations are often expressed in pounds per acre. To figure how much fertilizer with a particular analysis to apply, divide the recommended rate by the percentage of that nutrient given in the N-P-K analysis.

For example, to find out how much 12-44 fertilizer you need to match a nitrogen recommendation of 45 lbs./acre, divide by 0.12. and then convert to square feet:

45 lbs./acre ~ .12 = 375 lbs./acre 375lbs/acre + 43,560sq.ft/acre x 100sq.ft. = 0.9 lbs/100 sq. ft.

To find out how much phosphorus (P) is present in a given amount of phosphate (P2O5), multiply by 0.44. To translate soluble potash (K20) into plain potassium (K), multiply by 0.83. To convert the other way, divide by these numbers instead of multiplying. For other useful conversions, see page 208.


& AmIK

Guaranteed Anolyii».

Î 56% Ammoniocol Nitroçcn 1 16% Wtf* ln»oJubI* N.»OQ#/> 3 64% Mi'oeen

1 64* Sto»»V Awfaol« Watr Solvbh NfcOMO* AvoHooi9 rnotpkvf (PjO,J . 4 00%

IwM 075%

Pwxwy arte f.ortOory ntrtrfanfa 6+trr+c Wxyr,

Arr.TV>o wrr PhMphol«. Ur»o Sutfele w/ Po'ooh. Mlhytiwe Cop?»' Iron Ox**. MGWie— Owdo, Z/oc 0»id#

- *Sk^5y AraUoblr Mfrogan Ur«0



■is appear courtesy of Agicay Inc.

Lush Green Uaves Steady Growth for Weeks

. Our Evergreen & Azalea Food is custom blended with the growth to promote rich, green needles, deep roots ^¡pers. fir and root rot. Added iron helps prevent yellow,ng. Spruces, pme^em^a^y ji kj^ flourish flowering evergreens such as rhododendrons, azaleas, holl.es, cameras *ith this premium fertilizer.

individual Plants

^nng Wh«n new growt^ starts, spread fertilizer in a bf w^6 ** or $hrub fhe ,ip* of Qnches' but not on leaves or stems. Apply os follows:

I.andscape Areas

Sprood 2.5 Ibs per 90 sq. ft. {10 fî. * 9 h.) evenfy over londscope bed, keeping fertiliser on soîl unéer the tips of branches, r.ot on leavia or stems See diagrom ai right for cc^erogo

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