Alex M. Ilukena
Utete N. Christina
Food security is a global concern – and Namibia is no exception.
Over the years, there has been a profusion of deliberations on food production and security – and to reduce hunger and sustain food production, other agricultural practices had to evolve.
Among these is a technique called Hydroponics that has become inherently lucrative – and it is being used worldwide to improve food production.
The term hydroponics emanated from Greek words, hydro (water) and ponos (labour) – a soilless culture used to grow vegetables such as lettuce, tomatoes, scallions, cucumbers and bell peppers in a nutrient-rich solution (water and fertilisers) with or without using an artificial medium.
Food security in Namibia is crucial, and improving local food production, supplemented by food imports, has relatively addressed the issue of hunger.
Lately, soil-based practices have been impinged upon by factors such as floods, drought, climate change and the continuous use of chemicals, which led to the depletion of land fertility.
Additionally, another contributing factor is the alarming rate of urbanisation that has led to the curtailment of cultivatable land.
Withal, hydroponics can play a very important role in the agriculture sector if training workshops are conducted and materials that are used to construct the hydroponic system structure are made less exorbitant and obtainable.
To maintain a flourishing hydroponic system that works efficiently, the following major components should be in place: a growing media, the substitute for soil, to support the crop’s weight, anchors the root system, and delivers moisture and nutrients to the crop; it should be PH –neutral so that it does not influence the balance of the nutrient solution, air stones and pumps; crops need sufficient aeration when submerged in water.
They obtain their oxygen in form of bubbles from the air stones attached to the oxygen pump by opaque plastic tubing.
The opacity prevents algal growth.
Net pots are mesh planters that hold the crops, provide drainage and allow roots to protrude sideways and at the bottom, increasing the surface area for maximised exposure to oxygen and nutrients.
In addition, the water level, composition of nutrients and frequency of applying nutrients to the plant need consistent regulation.
Furthermore, light, as a source of energy, is a vital factor in crop production – and its absorption is maximised by growing the crops vertically in mobile multi-level bedding structures.
Superbly, if compared to soil crops, the hydroponic technique offers outstanding benefits such as fast crop growth, higher quality of crop taste and nutritive value, higher production yield, low water consumption, labour reduction in weeding, spraying, watering, no mechanical hindrance to root system, and less soil-borne diseases.
Crops are cultivated year-round, as they are not affected by climate change; water and nutrients are fed directly to the root structure and recycled within the hydroponic system.
Some of the limitations include lack of technical knowledge and skills, high initial cost, maintenance of pH and electrical conductivity (EC), hot weather, and limited oxygenation can limit crop production.
Crops share the same nutrient solution and can spread water-borne diseases from one crop to another.
Succinctly, it is important to educate people in hydroponics so that they can easily grow crops for their daily consumption in their compounds, and community members can also go commercial, improve their financial status, and eventually alleviate poverty.