Virtually any plant can be grown in a hydroponic system. However, many plants only grow well in specific hydroponic systems, and some plants don't grow particularly well in any. Leafy greens and most herbs are perfect for almost any hydroponic system.
The basics of hydroponics: answers to beginners' questions
Climbing plants such as tomatoes, cucumbers and peppers do well in hydroponics, but they take up more space and may need to be trellised. Melons are in the same situation: they do very well without soil, but they are big and need support.
What can be grown hydroponically?
Most root vegetables are not ideal for hydroponics, with the exception of green onions and garlic. It's not that you can't grow a potato in a hydroponic system, but it's simply inefficient and results in poor yields and wasted resources.
Do hydroponic vegetables taste different?
There is some debate about the flavour of hydroponically grown vegetables. The quick answer is yes, hydroponically grown vegetables taste different to those grown in soil. In fact, the flavour of all plants varies according to many factors, such as the type and quality of the soil or the time of year. A tomato grown in my garden will taste slightly different from one grown in yours.
The advantage of hydroponics is the control you have over the growing conditions of your plants. Nutrient levels, hydration and temperature can all be controlled to achieve the desired taste. In short, plants grown in different conditions may taste different, but hydroponic plants taste just as good as those grown in soil - there's no evidence to the contrary.
What does ‘hydroponics’ mean?
Hydroponics describes a method of growing plants without soil, in which nutrients and minerals are supplied to the root system by a nutrient solution. By first clarifying what plants need, we can understand what hydroponics is and how it works. Plants grow through the process of photosynthesis. Plants use sunlight and chlorophyll (a chemical in their leaves) to convert carbon dioxide and water into glucose and oxygen.
Soil is not a necessary ingredient in this recipe. Hydroponics means that the functions of soil in the growing process are replaced by simple alternatives that give the grower greater control.
How does hydroponics work?
In a hydroponic growing system, the plants receive light from the sun or grow lights, carbon dioxide from the air and water from the nutrient solution you provide.
In nature, soil is needed to provide nutrients and support the plant. In hydroponics, growers eliminate the need for soil by mixing nutrient-rich liquids or powders with water to create a nutrient solution. The structure and support usually provided by soil is replaced by plastic, or soilless growing media such as rockwool, perlite or coco-coir.
Let's look at a simple hydroponic system to see how it all fits together
In deep water culture, a plant is suspended above a reservoir of nutrient solution so that its roots are immersed in the liquid and its stem and leaves are in the air. The roots absorb water and nutrients, while the leaves absorb carbon dioxide and light. In this way, the plant receives everything it needs without soil - that's the magic of hydroponics.
Can you make your own hydroponic nutrients?
You can make your own hydroponic fertilisers at home, which saves you money and gives you greater control over the balance of nutrients. While many growers enjoy the convenience of a pre-mixed container of liquid fertiliser, others buy dry ingredients in bulk and mix them themselves with water.
