FERTILIZER. A brief introduction.

Ask any group of gardeners whether they prefer organic or chemical fertilizer, and chances are you’ll spark a lively debate.
However, if you could ask your plants the same question, you’d find out that they can’t tell the difference and actually do not care, nutrients are nutrients and all plant food first has to be acted on by soil microbes to be converted into a format the plant can use.
(This does not apply to hydroponics which uses a specially formulated plant food)

I have, however, noticed that many people do not understand what the numbers on a fertilizer bag mean.
Those numbers like 2-3-2 (14) or 3-1-5 (22)
They tell you the N-P-K ratios and the strength of the mix.
The 1st number is Nitrogen. (Promotes leaf growth.)
The 2nd number is Phosphorus. (Promotes root growth.)
The 3rd number is Potassium. (Promotes flower and fruit growth.)
The number in the brackets tells you what the concentration is.
The higher the number the more concentrated the fertilizer and the less you need to use.

The N-P-K ratios are important as you need different ratios for different crops.

Leafy plants like lawns, spinach, onions etc. need high Nitrogen.
Root plants like potatoes, sweet potatoes, carrots etc. need high Phosphorus.
Flowers and fruiting plants like roses, tomatoes, berries, pumpkins etc. need high Potassium.

ALL of these elements are essential for plant growth.
They are collectively called MACRO nutrients as they are what plants need most.
There are also many MICRO nutrients, equally essential for plant growth and health, but plants need these in tiny doses.

So where do these elements in "chemical" fertilizer come from.
Nitrogen is extracted from the air, (Did you know that the air is 78% Nitrogen)
Phosphorus and Potassium are produced from mined ores.
So while there may be a chemical process to extract them they are made from natural earth elements.

Some alternative sources of:
Nitrogen - blood meal, animal manure, plant material, urine
Phosphorus - chicken and horse manure, bone meal, fish emulsion, rock phosphate.
Potassium - animal manure, wood ash, kelp meal, granite dust, comfrey, banana peels, eggshells, coffee grounds, tea leaves, alfalfa pellets

I hope this brief introduction gives you a better idea of plant food.

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