Hydroponics Explained

Hundreds of years ago, agricultural researchers on whose shoulders modern agriculture rests, discovered that soil is unnecessary for plant growth.?

Simply put, plants do not consume, eat or absorb soil.?

What soil does is hold and in the right conditions, avail nutrients to plants for consumption.?

There are 17 essential nutrients. These are classified into 2 categories based on how much plants need them.

• The Macronutrients: Needed in large quantities. They include nitrogen, potassium, and phosphorus (NPK).
• The micronutrients: Needed in smaller quantities. They include iron, zinc, boron, molybdenum etc.

It is a whole periodic table.?

These elements are supplied to plants through the soil (as mentioned previously), water or air.

"What if we availed nutrients to plants without the soil?" Scientists thought.

This understanding gave birth to hydroponic.?

Legend has it that the hanging gardens of Babylon, built by a king for his queen (Ah. The beautiful lengths men go for the women they love) are among the earliest forms of hydroponic.?

Almost all plants can grow without soil. And for the few remaining ones, it is not a question of whether or not the plant physiology allows it to be grown without soil.

No, the question is of cost.

In its purest form, hydroponics is growing plants in water. Hydroponics is 2 words - hydro- (water) and -ponics (agriculture).

One crop that does well in a purely nutrient solution (water plus the 17 nutrients) is lettuce. Dip a seedling of lettuce in a nutrient solution - in 35 days you will have your head of soft leaves to make a burger or salad.

But, like people, crops do not like the same things.

The next form of hydroponic is better called soilless farming. Some crops like tomatoes will not do well when their roots are in constant direct contact with water

Therefore, while we will not use soil we must use another anchor called media to hold plant roots. The media can be cocopeat, pumice, rockwool, peatmoss and gravel.

The only requirement for the media is that it should not decompose quickly and be clean.?A colleague of mine experimented with growing vegetables using cigarette butts as the media.

Realising that plants can grow in anything other than soil was a powerful breakthrough:

1. It allowed farmers to grow plants anywhere. This includes reclaimed soils with zero nutrients, places with limited space, unsuitable weather, and soils where certain crops do not grow.
2. It allowed farmers greater control over plant nutrition.
3. It paved the way for the development of factory farms. These are industrial complexes, where food production occurs within factories using artificial light.
4. It allowed farmers to recycle irrigation water. Hydroponics system minimises water loss through evaporation or seepage into the ground. To urban farmers using county council water, minimising water through ground seepage is good news.

In conclusion, plants have no preference for where they get their nutrition.

It can be from soil, air or water.

To plants, Nitrogen from decomposed greens, urea - O(NH2)2 or calcium nitrate - Ca(NO3)2 is absorbed in the same form of nitrogen ions or N3 -.

Therefore, it is up to the farmer to choose based on her ability, expertise and environmental constraints - in what form to avail nutrients to plants.