Hydroponics

Hydroponics is a great way to garden if you have problems with mobility.

Using hydroponic techniques, it is possible to create gardens that are partially or fully automated, on table tops, or raised stands; and which don't require any heavy work such as digging.

Hydroponics has become popular amongst many disbled and elderly gardeners across the world, as well as hobby gardeners who simply find it fascinating to grow plants without soil, or through application of technology.

ACS Conducts a Home Hydroponic Distance Education Course (click here for details)

Hydoponics in simple terms is the growing of plants (commonly herbs, vegetables and annual flowers) without the use of soil. It can involve growing the plants in rocks, sand, in a channel that has a thin film of water flowing in it, or even suspended in air. Nutrients are supplied to the plants by a liquid solution either continuously or applied periodically.

The advantages of hydroponic culture for food include:

  • More control over growth - it is possible to make plants grow taller or encourage quicker flowering.
  • It is environmentally friendly - waste from fertilisers can be caught & and reused or suitably disposed of.
  • There is more control over pests & diseases - as hydroponic plants are kept off the ground they tend to be cleaner and less likely to be affected pests or diseases. Hence, use of pesticides is reduced, if not eliminated.
  • Less manpower/less back-breaking work is required. Using raised benches to grow plants hydroponically ensures a lot less bending is involved compared to in-ground production. This is an important consideration for the elderly or impaired.
  • Crops can be grown out of season - as plants are grown out of the soil and tend to be grown with more environmental protection, crops can be started earlier, and grown later in the season.
  • Hydroponic systems can be more productive per unit area - this means that for a given area of space, hydroponics can produce more edible food than compared to soil culture. For people who have limited space this is great news.
  • You can produce crops with low levels of potential toxins compared to crops grown in polluted soil.

Disadvantages of hydroponic food culture are:

  • You need more expertise than soil growing - growers will need to read about nutrients and irrigation, in particular, in more depth than the average gardener.
  • It is more costly to start up - depending on the type of system you wish to set up the costs may range from under $100 to a few thousand dollars.
  • Food quality is regarded by some people as being poorer - this may relate to the fact that soil has biological organisms that can contribute to the nutrient value of the food. If these organisms are omitted from the plant growth, then it is possible that the food may not be as nutritious as soil grown plants. However, there is strong evidence that ionising the nutrient solution can more than overcome this problem. An Australian company QuantumPONICS has developed systems that use the same principles that nature uses when creating Quantum fields to ionise nutrient solutions and irrigation water . Numerous trials around the world comparing such systems with standard systems, have shown that plants grown in ionised hydroponic nutrient solutions grow much faster, healthier, and tastier with higher yields, and much higher nutrient levels in the harvested produce.

Suitable Hydroponic Systems for the Home Grower

The main types of hydroponic systems available for the home gardener include:

 

NFT - this refers to Nutrient Film Technique. NFT uses a channel (like a pipe) to carry water and nutrient solution into which roots of plants are suspended. Plants progressively take up water and nutrients as they require. This is possibly the most popular and efficient system available. Nutrient solutions can be caught at the bottom of channels and recirculated, or allowed to run-to-waste. The channels are sometimes filled with coarse sand or stones, but water absorbing material such as perlite should be avoided, as it can cause root rots.

 

Suitable plants to grow:

Tomatoes, cucumber, lettuce, beans, broccoli, cabbage, cauliflower, celery, chicory, corn, eggplant,

capsicum, okra, herbs, spinach, strawberry, pepino, snapdragon, stock, chrysanthemum.

 

Aggregate - this type of system is usually the first system people try out. It involves growing the plant in a pot or container that holds rocks, stones or some other type of aggregate. Water and nutrients are generally supplied by a flood and drain mechanism (ie water is flushed into the container then allowed to drain away), or by a simple drip irrigation pipe that continually supplies a small quantity of solution.

If the media used is poorly drained, root rots can occur. Avoid too much vermiculite in any mix. Irrigations should not be too frequent in cool weather.

 

Suitable plants to grow:

Jerusalem artichoke, Asparagus, Garlic, Leek, Lettuce, Melons, Onions, Potato, Cabbage, Cauliflower,

Broccoli, Brussels Sprouts, Pea, Radish, Tomato, Strawberry, Herbs, cut flower Bulbs, Carnation,

Chrysanthemum, Pineapple,

 

Unsuitable plants:

Root vegetables such as carrots and parsnips are more difficult.

 

Rockwool is a spun rock fibre product similar to roof insulation batts, but specifically designed for hydroponics. Slabs of Rockwool are generally laid on the ground or floor surface. These are then planted up with herbs, vegetables or flowers and fertigated (water and nutrients) usually by drip irrigation systems. Large plants become top heavy and need trellising. Algae can grow on the rockwool surface, then die leaving a water resistant coating on the surface. Avoid this problem by keeping as much of the surface as possible protected from light; which can be done by using plastic wrapped slabs. Rockwool slabs are generally not reusable.

Suitable plants to grow:

Jerusalem artichoke, Lettuce, Melons, Onions, Capsicum, Cucumber, Eggplant, Zucchini, Pumpkin,

Tomato , Strawberry, Carnations, Chrysanthemum, Rose, Gerbera,

 

Unsuitable plants: Root crops

Manual Or Automatic?

The systems can be manual or automated. Manual systems will require you to spend more time ensuring water and nutrients are applied, and that the system is running efficiently. An automated system will aim to use monitors and electronic readers to help reduce your maintenance. It can also automatically irrigate and fertilise your plants. Automated systems will be initially more expensive, but can save you a lot of time and effort later on.

 

ACS Conducts a Home Hydroponic Distance Education Course (click here for details)