Earth & Sky

Hydroponics: growing plants without dirt

Plants don’t really need dirt to grow.

But plants do need the things that dirt provides.

So you might think of dirt as a sponge that holds everything a plant needs. Plants need water, oxygen, and many different nutrients – you know, food for plants. Throw in sunlight and carbon dioxide – and you have everything needed to grow a plant.

Dirt holds onto nutrients and helps keep them from being washed away. Dirt also helps hold plants upright. But, as long as a plant is getting the things it needs – and if you have a way to keep it standing upright – even a big plant, such as a tree, can grow in sand or even water.

There’s a special name for growing plants in water. This process is called hydroponics. People who use hydroponics have a lot of control over their plants – because they control the nutrients, oxygen – all the things the plants need. They can change how fast and how big the plants grow by changing the conditions in the water.

Also, it takes less room to grow plants using hydroponics than to grow plants in dirt. That’s one reason why some people imagine a day when hydroponics may be used in outer space – to grow food for space travelers. They might even use water taken from a comet!

Written by Tara Ross, Deborah Byrd, Marc Airhart

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3 Comments for Hydroponics: growing plants without dirt

1. 1

   Aug 28, 10:19 PM #

   alyssa says:

   How? Will the plant/plants be healthy?

2. 2

   Sep 6, 10:13 AM #

   John Scheer says:

   hi i like eggs

3. Sep 6, 06:05 PM #

   Deborah Byrd says:

   Hi Alyssa, yes, the plants will be healthy. You put their food right into the water.

   Hi John. I like eggs, too.

   Have fun!

   Deborah