What does hydroponics have to do with Martian omelets?

Lemme tell you, if you were stuck on the space station for six months and started craving a Denver omelet, Hydroponics would save the day. 

But let's back up.  First, what is this Hydrowhatchamacallit?  Although we are used to seeing plants grown in soil, they do not actually need soil to grow.  Hydroponics is a growing method which utilizes water and dissolved nutrients.  “Hydro” = water and “ponos” = labor.  Thus, hydroponics basically means “working water”.

There is a whole grocery aisle of benefits to hydroponics farming.  First, by growing in water the absorption of nutrients is accelerated.  The growth rate on a hydroponics plant is 30-50 percent faster than in a soil plant grown under the same conditions.  This makes for greater yields (more!) over less time and utilizing less space.  Hydroponics systems pump the necessary nutrients right to the plant.  Thus, roots do not spread as much as they do in soil.  Scientists believe that the growth rate of hydroponically grown plants is greater because the plants do not have to search in the soil for the nutrients they require and this saved energy allows them to grow faster and produce more.  Pretty cool.
Martian omelet? 

That's right.  For many years NASA has been developing ways for space station astronauts and eventually planetary colonizers to generate their own food.  It's a must as there is no economical or feasible way for them to bring 3 years of food supplies with them.  In space, where longer term life will need to be sustained as we venture out further and further, hydroponics proves to be the most efficient way to generate fresh foods.  it will  help reduce the weight of the supplies that need to be lifted off the Earth. 

And, since space is at a premium in outer space settlements, colonists will need to use  more efficient agricultural techniques than those used on Earth. Even though hydroponics does not require soil and takes up less space than  normal methods, plants grown hydroponically are often larger and healthier than plants  grown normally. Hydroponics also is a cleaner method of growing plants than soil-based  systems. It is also thought that dirty water produced by the astronauts could be cleaned by  cycling it through a plant system.

Enough with the geeky stuff?  What can they eat?

As long as they have the seeds and the space to do so, astronauts can literally grow anything their tummy's desire.  Basil.  Tomato.  Spinach. Oranges.  Bananas.  Mushrooms.  Anything.  So what we'll have are happy, healthy astronauts with some green, yellow and red goodies from home to keep their tummy's smiling.  All thanks to hydroponics.