If you've heard of this word, it may have been on the news due to some illegal drug growing operation in someone's garage. That, or you saw the word on the packaging on some very good looking and expensive lettuce. If not - kudos to you :D
What is hydroponics?
Basically, growing plants without the use of a traditional dirt medium and using a nutrient rich water solution. Those mediums range from fiberglass to sand and from fired clay balls to nothing at all. Several branches of hyrdoponics include aeroponics (using air as the grow medium), aquaponics etc.
How do I get started?
Well, you can buy a kit - but its going to cost you... a lot. Or, you can improvise and create your own kit to suite your needs. My local hydroponic supplier's cheapest multiplant kit is $185, does 8 plants but is not very versatile and is very compact. It uses the ebb and flow method. They also offer a single pot (bucket) bubbler system for $50. We are going to combine these two systems into a more versatile and much cheaper system.
What are my options
There are many different methods. NFT (nutrient film technique - stream a thin layer of nutrient solution over the roots) is common among professional kits - a long with ebb and flow (temporary flood your root system and allow to drain). The most interesting method involves suspending your plants in mid-air and spraying the root system very frequently (aka aeroponics). Drip systems are also common and has its own advantages. There are MANY methods - all of which do not use dirt ;)
What method is used here?
By far the simplest and cheapest is a bubbler system. That is, keep your pots filled with your choice of medium just barely above your nutrient solution level -- then keep the solution well aerated. The popping of the air bubbles will keep your medium moist. Remember that more simple and more cheap does not mean less effective ;)
What Medium is used here?
I have used several different mediums in the past. Chopped rockwool, rockwool cubes/blocks/slabs, fired clay and a combination of rockwool and fired clay. This system will work best with chopped rockwool (cubed) or fired clay (extra attention is needed if starting from seed with this medium).
I'm in college - so cost is very important to me. This can be a very cheap project if you collect parts slowly. And luckily, the parts list is not long and they're not rare. I believe I have spent a total of $30 for new materials - however I did buy a few items in bulk and I splurged a little :P
Hydroponically grown foods not only taste better and are more nutritional, you can change the properties of your food, monitor what goes into your food and pollutes less. You can also grow more in less space. This is especially great for those of us that do not have a backyard to grow in. With the right plant selection, you can also keep pests away. I plan on planting a citronella plant - not only do I like the smell of citronella plants, but their oils keep away mosquitoes and other pests.
This design is in no way novel... but, it is easy to do - especially for someone just starting or someone with little money.
Excited? I am. Lets go!
Step 1: BOM - Bill of Materials
Parts and supplies
1.Opaque container that can hold water with lid (I am using an old 18 gallon storage bin)
2. Mesh Pots (how many depends on what you're growing and the size of your container - I am using 6 5.25" pots) ($9.90 for 6 heavy duty)
3. Rockwool Growcube (chopped rockwool) (5.95 for three gallons)
4. Growing Solution (I have used Dyna-Grow brand 7-9-5 with excellent results) ($12.95)
5. Aquarium air Pump (nothing special) (already have/not using)
6. Air Stone(s) and air hose ($3)
7. See the start growing step for additional instruction
Recommended but optional
1. Syringe - for making more precise measurements of growing solution ($2.60 for 60mL)
1. Razor Knife
3. A compass would be nice