Plant Plant NutritionNutrition

Mrs. GillMrs. Gill

Pee-Cyclinghttp://www.npr.org/blogs/thesalt/2014/07/31/336564120/should-we-return-the-nutrients-in-our-pee-back-to-the-farm

Major Nutrition 3 Major Elements

oxygen (O) hydrogen (H) carbon (C)

Considered to be non-fertilizer nutrients and make up 96% of plant’s tissue

Acquired through natural processes from air and water

Macro Elements Divided into two groups, macro

and micro Macro

Nitrogen – NPhosphorus – PPotassium – KCalcium - CaMagnesium - MgSulfur - S

Micro Elements

Chlorine – Cl

Iron - FE

Manganese – Mn

Boron – B

Micro Elements Cont..

Zinc – Zn

Copper – Cu

Nickel – Ni

Molybdenum - Mo

Soil testsDetermines which nutrients are present and which are deficient for growing a variety of crops

Soil Sampling (Simplified)

Take random samples from the area to represent the area you want to test

Mix all of the samples together

Complete the soil test info sheet

Mail the sample and info sheet to a reputable lab Usually a University Extension Program

Analyze results and make production decisions

Plant Requirementslarge amounts of major elements

relatively small amounts of minor elements

Fertilizer Any material added to a growing medium that provides nutrients for plants

Vary in what they contain, how they are applied, and the function they serve

Commercial fertilizers

The fertilizer analysis shows % or pounds per cwt. (100#) of the three major elements in large numbers on the container or bag

Nitrogen (N), phosphate (P), and potassium (K) or Potash

Commercial fertilizers

5-10-5

5% N, 10% P, 5% K

remaining 80% is filler

NP&K are always listed in that order.

Fertilizer Forms• Liquids

Salty so they dissolve in water

Sprayed on root zone or as a foliar application

Have high tendency to ‘burn’ plants

Are usually short-lived

• Granules Most common form

Heavy pellets don’t drift too far

Can be slow-release

Fertilizer Forms• Tablets and Spikes

Large compressed items that are pushed into the soil or placed in a hole

Expensive for the amount of nutrient they contain

Release nutrients very slowly over time

• Several months to more than a year

Nutrient Solutions Nutrients in solution are measured in parts per million or PPM.

Fertilizer rates can be taken from tables in reference books or to instructions with their injector system, or growers can calculate the amount of fertilizer needed to reach a desired PPM.

An example problem might call for 200 PPM nitrogen.

The chosen fertilizer is calcium nitrate with an analysis of 15-0-0.

A rule of thumb in calculating PPM is that 1 ounce of anything in 100 gallons H2O equals 75 PPM.

Problem: Wanted, 200 PPM N 15-0-0 Calcium Nitrate Multiply the percent of the

nutrient in the given fertilizer by 75.

.15 N × 75 = 11.63 PPM N (if 1 oz added to 100 gallons) 200 divided by 11.63 = 17.2 oz of fertilizer needed in 100 gallons to get 200 PPM.

If the injector system delivers 1:100 (one gallon concentrate mixed with 99 gallons water for a total of 100 gallons), 17.2 ounces of fertilizer is needed for each gallon of concentrate.

If the tank holds 30 gallons of concentrate, 516 ounces (32.25 pounds) of fertilizer is needed to deliver 200 PPM

Choosing a Fertilizer

Things to consider Nutritional need Application method Price Availability Personal Preference Safety/Environmental Concerns

Placement is critical—GPS systems

Nitrogenhas most noticeable effect on plants

encourages above ground vegetative growth

regulates use of other elements

Leaches easily

Too much Nitrogenlowers disease resistance

weakens stem because it promotes long, soft growth

lowers fruit quality

delays maturity

increased susceptibility to cold

Symptoms of Nitrogen

Deficiencyyellow or light green color

stunted root and top growth

Nitrogen Deficiency in

Corn

Phosphorousheld tightly by soil particles

not easily leached

Phosphorousencourages cell division

flowers and seeds don’t form without it

hastens maturity, offsetting quick growth caused by nitrogen

Phosphorousencourages root growth

makes K more available

increases disease resistance

improves quality of grain, root and fruit crops

Insufficient Phosphorus

susceptibility to cold

susceptibility to plant diseases

poor quality fruit and seeds

Symptoms of Phosphorus Deficiency

purple color on underside of leaves

reduced flower fruit and seed production

PotassiumWorks with Nitrogen and Phosphorus to improve plant growth

development of chlorophyll

efficient use of CO2

Potassiumincreases disease resistance

encourages healthy root systems

essential for starch formation

Insufficient Potassium

leaves appear dry and scorched with irregular yellow areas on the surface

LimeCaCO3- Calcium Carbonate

acts as a plant food

affects soil acidity

soil acidity affects availability of plant food elements

Is Soil Alive?¼ teaspoon of fertile soil contains approximately:

- 1 Earthworm

- 50 Nematodes

- 52,000 Algae

- 111,000 Fungi- 2,920,000 Actinomycetes

- 25,280,000 Bacteria

Earthworms Decompose organic matter

Mix plant litter with soil

Tunneling helps with aeration of the soil

NematodesExamples are:

Roundworms, threadworms, hair worms

Consume other microbial organisms which help regulate the microbial population

Also found in the roots of the plants

Algae Contain chlorophyll (photosynthetic)

Soil algae are too small to be seen with the naked eye, but in large numbers can give the surface a green color

They favor damp soil that is exposed to the sun

Help with the formation of soil structure

Fungi Examples:

Mushrooms, mold, mildew, rusts, yeasts

Grow on dead and decaying tissue

Primary agent of organic matter decay

Make nutrients available by decomposing organic matter.

ActinomycetesRod-shaped form of bacteria

Can live under drier conditions than bacteria, very abundant in sod

One of the most important agents in the soil for decomposing and breaking down cellulose

Its what gives freshly tilled soil its smell

Bacteria Most numerous and MOST IMPORTANT!

Diverse metabolism aides in breaking down organic chemicals like pesticides

Can also degrade inorganic materials

Fix Nitrogen so it can be used by plants

Why do we need microorganisms in

Agriculture? Decay plant residue

Fix nitrogen

Break down nutrients needed by plants

Break down cellulose

Finally, much of the soil is not available to the plants until the microbes break it down