Planet Veggie Garden

Jumping on Sandy’s compost post, I thought I’d explore fertilizers a bit.

The end purpose of composting is to create nutritionally dense organic material to feed - or fertilize - the soil.
The definition of fertilize being: to make fertile, to enrich the soil by adding organic (or chemical) substances.

Agriculture has been around for 11,000 years give or take. As you may guess, fertilizing the soil isn’t a “new” thing.

The core plant nutrients are Nitrogen (N), Phosphorous (P) and Potassium (K).
How much of what you need depends on the breakdown of your soil and what you’re growing in it.

Nitrogen is the most needed nutrient. It’s an essential building block used to assemble amino acids, nucleic acids and protein. Nitrogen is crucial to life.
Nitrogen needy plants are more “life less”… yellowed, smaller and less fruiting.

Before commercialization

Organic manures and guano were popular fertilizers.

There are two classes of manures: green and animal.
Green manures are crops that are grown with the specific intent of plowing them under. These are also called “cover crops”.
For instance Legumes are nitrogen rich… when they’re plowed under they add nitrogen back into the soil. Soy beans were originally only used as a cover crop.

Animal manure is the feces from certain mammals including horses, cows and chickens. All are grass/plant eating animals and produce nitrogen rich manure.

Guano is feces from sea birds, seals and bats… again, nitrogen rich and high in phosphorous as well. Also has fungi and bacteria that act as a natural fungicide for plants.
The term originated in Peru.

Commercialization of farming and fertilizers

There wasn’t much in the way of commercial fertilizers before 1900.
In the 1890’s agriculture started becoming less family farm with a horse drawn plow and more mechanized and commercialized.
Along with that trend, commercial fertilizers became part of the mix.

Chemical fertilizers came along in the mid 1800’s. Ammonium Sulfate, Ammonium Nitrate, Calcium Nitrate, Sodium Nitrate.

Ammonium Sulfate was originally a by-product from coal gas manufacturing. The quality wasn’t great as a fertilizer but it was used some in the 1800’s.

Sodium Nitrate was the first popular fertilizer and used in the early 1900’s.

Ammonium Nitrate came into vogue after World War I.
Ammonium Nitrate was the principal ingredient used in explosives. Following War I, it made it’s way to the fields in significant volume… more so in Europe than the US. Following World War II with a large surplus in the US… why not “explode” crop growth ;).

Ammonium Nitrate is an inorganic source of nitrogen.

Big versus Small; Inorganic versus Organic

Large industrial agriculture is still a big user of chemical inorganic fertilizers. However, organic farms, home gardens and some smaller farms favor organic fertilizing.

In the US this is most typically in the form of compost and animal manures.
Being urban farmers, we go for the horse manure from a nearby stable and we’re working on our little compost factory.

Farms (organic and smaller) also are conscientious about crop rotation and may use “cover crops”.

 

Here are a few more like this one:

• NPK: Plant macronutrients
• Brief history of pesticides
• Compost your way to great veggies