Vegetables growing in a large hydroponic greenhouse

Hydroponics for beginners

If you are new to the world of hydroponics, then this method of growing plants can look pretty intimidating. You’ve probably seen pictures of enormous greenhouses, packed with rows and rows of neatly arranged lettuces and thought little of it. Then you’ve looked again and realised that the lettuces are sprouting out of holes in plastic tubes rather than 3 foot of soil. 

It all looks very space-age and as if you need a couple of degrees in biology before you can successfully grow a bunch of parsley.

The reality could not be further from the truth.

Hydroponic vegetables growing in a greenhouse

What Does Hydroponic Mean?

Hydroponic is a word made by putting 2 words from the ancient Greek language together. The ‘hydro’ part means water and the ‘ponic’ comes from ‘ponos’ which relates to labour or toil. So hydroponics literally means working with water, which is exactly how plants are grown using this method.

For more on the origins of the term ‘hydroponics’ please see A Quick History of Hydroponics

What is Hydroponics?

Hydroponics is a way of growing plants without soil.

A plant gets the same nutrients as it would from a patch of soil, but through a specially prepared nutrient-rich solution. This is basically water but  bumped up with all the minerals etc that the plant needs to grow. These minerals can be added to the water either through traditional sources like fish excrement or specially created solutions.

What are the Advantages of Hydroponics?

There are multiple advantages to growing plants, in particular certain crops, using hydroponics.

Water Conservation

To grow a lettuce using conventional methods, you would plant the seedling in a patch of soil and water it. This can cause a number of problems:

  • The water seeps into the soil and only a tiny amount of it actually goes to the seedling.
  • The water can actually go to other plants, like weeds, which can ‘strangle’ your crop.
  • The grower needs to be knowledgeable about how much and how often to water the lettuce. Too much and the roots will be starved of oxygen. Not enough and the lettuce will shrivel and die.

In contrast, with hydroponics:

  • The roots of the lettuce are in direct contact with the nutrient enriched water.
  • The only plant getting the nutrients is the one that you want to grow.
  • Any water that isn’t used by the seedling can be recycled back into the watering system and used again.

To emphasise the difference in the water usage between traditional soil farming and hydroponics, it can take up to 400 litres to grow 1 kilogram of tomatoes with regular intensive farming. Hydroponics can produce the same kilo of tomatoes from only 70 litres of enhanced water.

When you apply that to the thousands of tonnes of tomatoes that are grown in Australia alone each year, you can imagine the incredible difference this makes to water consumption. Especially in a country like ours where drought is a major problem in many farming regions.

Oxygenated Water

The reservoir that holds the water can be oxygenated. This means that the grower can ensure that the plant’s roots are getting the ideal amount of oxygen to it to thrive.

Control over the Nutrients Supplied to the Crop

The grower has incredibly precise control over the amount of water, oxygen and concentration of nutrients that each individual plant gets. 

Hydroponic vegetable garden illustrating pipes and pump

Soil-Based Diseases & Pests are Eliminated

Obviously, if there is no soil, then any harmful bacteria or bugs that need some kind of earth to survive are no longer a threat.

More than this, hydroponic systems are generally up off the ground and self-contained, which means that it’s harder for many insects and pests to get to them.

Hydroponic kits are also portable. So if you are unlucky and get an infestation of some kind of bug, you can physically pick up your lettuce plants and move them to a new, safe location. Try doing that with a field of cos!

Remember: There is a reason why pesticides are such a huge cost for conventional farmers. Hydroponics systems help to combat this expense.

Space Efficient

You can grow far more of a crop in the space that you have as you can plant things more densely using hydroponics.

Plants Grow Quicker

As you are providing your crop with a custom-made cocktail of nutrients in a perfectly controlled environment, they will mature faster.

Produce grown hydroponically also tends to look better than it’s soil-raised cousins and it lasts longer too.

Strawberries growing hydroponically

It Outplays the Rain Gods

With hydroponics, you can plant your crop all year round without worrying about rainfall patterns or even the possibility of drought seasons. 

You are controlling the water supply, not the heavens.

Can Grow Crops In Unexpected Locations

As long as you have a water supply and the right nutrients, you can practice hydroponics.

This means that you can raise crops in places not known for their arable land. Growing tomatoes in a desert is perfectly possible using hydroponics, though possibly not very environmentally friendly!