WHAT IS HYDROPONICS:
When plants are grown naturally, the soil serves two purposes:
1. provide support for the plant
2. provide the plant with water and nutrients.
Besides water, there are 16 nutrient elements plants need to take up from the soil through their roots. These can come either from organic sources and organic fertilizers (such as compost, animal manure) or anorganic fertilizers (MiracleGro, "no brand" N-P-K fertilizer etc).
In hydroponics (HP), the plants are suspended in some kind of support system, and their roots are constantly or periodically sprayed with or immersed in a water / nutrient mixture.
One of the most popular HP systems both among hobbyists and commercial growers is NFT (Nutrient Film Technique). I'll concentrate on NFT here.
This image will show you the schematics of an NFT system.http://www.simplyhydro.com/images/nft.gif
The plants are grown in a trough or pipe. A thin film of water/nutrient mixture is kept flowing constantly at the bottom of the tray. The nutrient solution is held by the reservoir
, and is recirculated by a small water pump. (The airpump+airstone are optional items)
The roots of the plants grow down, into the nutrient mix, and eventually build a thick "carpet" on the bottom of the tray.
ADVANTAGES OF HYDROPONICS:
* water usage is minimum. (there is no runoff and only little evaporation)
* fertilizer usage is minimum. In a dirt garden, you have apply a lot of water/fertilizer mix to reach the roots of the plant -> a lot of it is wasted.
( For example, MiracleGro recommends 1 tablespoon fertilizer per each gallon of water to fertilize your plants in a dirt garden. In contrast, when using MiracleGro as a hydroponic nutrient (which is possible with some caveats), 1/4 of a tea
spoon per gal is sufficient for some impressive vegetative growth in the system. )
* HP plants are generally larger and faster growing than dirt plants, because the root zone and nutrient conditions are optimal, and the plants never suffer "famine" or "drought". They are always well fed and can develop at a fast speed.
* Because you grow without soil, the chance of soil-born diseases is at a minimum.
* You can grow hydroponically pretty much everywhere. I know that the researchers at the north pole have a small hydroponic garden to grow some greens - the only fresh food they eat. There is quite an acreage of hydro tomato growers in the cooler regions of Canada. There's eggplant growing in New Zealand in the winter. HP can be an interesting niche to get into, making possible to grow unusual, out-of-season, or impossible to grow crops in the given region and to sell it at premium prices.
likes HP include further:
* I have no dirt garden.
* I like to plan and build things.
* I dig the Cyborg theme. (building "green machines" out of man-made materials such as plastic and metal).
* Also, because I don't have a house and am not settled down, it's seems very practical that I can disassemble my gardens and take them with me wherever I may go and live. I can get back to growing quickly and easily, even in an apartment, if only to grow a few herbs.
DISADVANTAGES OF HYDROPONICS:
* Cost & complexity. Obviously, getting into HP requires some learning and and some investment. How much, depends on your abilities, goals and $$$ (see below).
* Some systems (such as the NFT we're discussing) are very sensitive to power outages. If no precautions are taken, it's possible for the whole garden to die within a few hours, if power goes out (or the system breaks down otherwise) on a hot summer day. (However, not all HP systems suffer from this problem, and even NFT's tolerance for system failure can be improved).
* Sometimes the nutrient solution can transmit diseases. This happens very fast and all plants could be infected in only a matter of hours.
They are different from dirt fertilizers, in that they are of higher quality (=high purity, high accuracy of nutrient amount measurement). Store-bought HP fertilizers usually contain a good mix of nutrients, suitable for most any plant and situation.
GETTING STARTED IN HYDROPONICS:
It all depends on your financial situation, your interest in planning and building things, and the time you are willing to invest in your new hobby.
The endpoints of the spectrum are:
* build your own systems, mix your own nutrient solution, start your own plants from seed / cuttings -> cheapest, however most time consuming, requires good knowledge of HP, building things, seed starting, etc.
* buy systems, buy seedlings and buy the nutrient solution -> most expensive, but fastest - gets you growing immediately.
Currently I am (and most other hobbyists are) building my own and starting my own, but I use a store-bought nutrient. This keeps the costs low, and the fun factor high.
STORE BOUGHT SYSTEMS
These are a great way to get growing fast (although I never had one).
Unfortunately, the large number of yuppie pot growers drives the price of hobby hydroponic systems high. The systems are quite posh, and the sellers have large profit margins. (Blame the war on drugs for that one as well...)
But no question, these systems are nice, look good and work very well, and can get you up and growing instantly.
... costs $400, but could be built for less than $100, including pump and reservoir.
If you go the this route, you'll need some tools, but not many. I do all my hobbyprojects with hand tools and a Dremel
. Occasionally I'd rent a larger power tool).
Parts you'll need include plumbing supplies, PVC pipes/gutters, drip irrigation components, pumps, hoses, and plastic boxes / trash cans / totes suitable as reservoir. Your local Home Depot or O.S.H. should have all of these.
Coming up..... One of Oatmeal's gardens.