Hydroponic gardeningAll about hydroponic gardening information

Control is the key to success here. Having control over every aspect of your mini biosphere is crucial to growing the best plants and having fruit and vegetables all year round. The main limiting factors of this project are of course the cost of construction, the equipment and how much space it’s going to take up. The investment could be worthwhile, as it may well save you a fortune on grocery costs. Home grown produce is also much healthier and fresher!

Humidity can be controlled by having flowing water run around inside the parameter of the structure. It can then be heated or cooled depending on how humid the place should be. Using a series of heating elements is fine for this task, but there is a more advanced way to do it. Thermoelectric units, called Peltiers can be used to heat, cool and even freeze the water. Control of these units is very simple too, as reversing the polarity will cause them to cool or heat the water depending on how it has been set up. The only limiting factor is cost, both in the price of the units and the power required to run them. You are going to need a lot of these units distributed around the water trench depending on the size of your hydroponics structure, and that could mean big power bills. A combination of Peltiers and heating elements could by used to make the system more efficient, using the heating elements to heat the water up to increase humidity and the Peltiers to accelerate the cooling of the water. Since most plants grow well in warm and humid conditions, it may be unnecessary to use Peltiers at all.

Insulation is very important to this project, as it will determine how efficient the whole environmental heating system is. A well insulated hydroponics structure will also save you money on the heating bill! Good insulation will also make the environment more stable as the plants will experience a smooth temperature gradient throughout the day.

It is theorised that plants have circadian rhythms just like people and animals do. So at night it is a good idea to have your system simulate a cooler, but still slightly warm night. You may also want to try out installing a daylight cycle system that simulates sunrise, mid day sun and sun set. This can be done with three separate lighting circuits, each with timed variable resistors so that they seamlessly fade into each other, creating a perfect daylight cycle. Using high quality day light bulbs is also a good idea, so that the full light spectrum of the sun is simulated as accurately as possible.

Obviously you will need some kind of irrigation system to water your plants. A basic hose that runs around near your plants is fine, but it could be made even better. Plants like to get their leaves wet, having your watering system high above to simulate rainfall will hydrate every part of your plants. There is a study which suggests that wind is important to the overall strength of a plants stems and branches. It makes sense because if plants weren’t to adapt to windy conditions, they would snap in the wind. I have also tested this theory out on my own plant. Prior to a weeks worth of 10 minute sessions in front of a fan, the stem was fairly flexible and weak. After one week there was a noticeable difference in the rigidity of the stem and it was much stronger.

It may sound a little crazy, but why not set up a number of fans in your hydroponics structure to simulate anything from light breeze to moderate gusts. You could even set your own programs, such as storm, which could involve strong winds, heavy rain and if you have some speakers around why not add in some thunder sounds!

Another theory is that certain sound frequencies can stimulate plant growth, such as the sound of birds. Some even think that music can help stimulate plants too. Setting up a series of speakers in your structure is quite easy and cheap to do, and can be set to play/loop sounds or music.

The final theory is that electricity can stimulate plant growth too. It has been observed that in some cases where lightening has struck the ground, the surrounding vegetation has grown a lot better than others near by. This could be due to the nitrogen that is deposited on the surface of the ground after a strike, but the amount is minuscule. Plants have been known to grow towards electrostatic field sources, so this may be something to look into!

With taxes skyrocketing along with food prices, now more than ever is a good time to start growing your own food. After all, it’s healthier, fresher and of course absolutely free!

By: Tom C W Higgins

The term hydroponics stands for the technique of cultivating plants in a nutrient solution rather than in soil. It’s a novel technique of growing plants in water which contains dissolved nutrients. This technique is also known as indoor gardening, aquiculture and tank farming.

Studies have proved the fact that plant roots are able to absorb the nutrients from the water even without soil. The new technique hydroponics is based on the concept that plants can be grown without any soil at all.

Professor Gericke of the University of California, Davis, is considered the father of hydroponics. Professor Gericke, in 1929, proved his invention by growing tomato plants in water to a quite remarkable size. The Professor coined the name hydroponics for the culture of plants in water.

Almost any plant can be made to grow through hydroponics. Today, the new techniques of hydroponics gardening and hydroponics farming are becoming popular.

Benefits of Hydroponics:

Hydroponics is a very useful technique when there is scarcity of land, and it is growing extremely beneficial and profitable to farmers. The positive aspects of hydroponics are listed below.

Hydroponics –

o Gets rid of soil-borne diseases and weeds.

o Requires no soil tilling or ploughing.

o Helpful in land scarcity; plants can be placed very close to one another.

o Can be done in small spaces.

o Highly productive; high yield, large amount of food can be produced from small spaces.

o Requires only a small amount of water compared to traditional farming.

o Allows the production of quality plants under controlled environmental conditions.

o Makes it possible to grow plants all year round.

Future of Hydroponics:

The future of hydroponics seems to be quite bright. As plants are grown indoors, they can be made to grow almost anywhere, in any condition and any weather.

It’ll make it possible to grow plants in Antarctica. The techniques such as hydroponics or aeroponics may make it possible to grow vegetables and fruits in space in some near future.

By: Paul MacIver

Hydroponics literally means “working water” (hydro=water, ponics=work). Practically, it means growing plants without using soil, delivering nutrients only by a aerated nutrient solution.

Hydroponics systems can be either closed or open systems. In closed systems the same hydroponic nutrient solution is recirculated and the nutrient content is monitored and adjusted.

Keeping the nutrient balance in such systems is a challenge and the hydroponic nutrient solution has to be sampled and analyzed every week. The nutrient solution composition has to be adjusted according to the results.

In open systems a fresh nutrient solution is introduced for each irrigation cycle.

Inert growing media are usually used in hydroponics. Unlike soil, that stores nutrients and directly interacts with the plant, the growing media used in hydroponics have little effect, if any, on the plant nutrition. As a result, the only source of nutrients is the nutrient solution, and therefore you have total control over your plant nutrition.

While soil allows more tolerance for inaccuracy, hydroponics leave very little room for errors. Because changes are rapid and mistakes can be very costly, hydroponics growers should make highly educated and accurate decisions.

Close monitoring of Water content is extremely important in hydroponics

Naturally, water plays a major role in hydroponics, making their quality and content – paramount.
There are several key questions that should be addressed when dealing with this issue:
Which nutrients are required? Are they all present in the correct concentration in your hydroponic solution?

What are the ratios between the nutrients? Do some nutrients affect the availability of others? What is the total concentration of minerals in the solution? Are there any harmful elements in the water? What is their concentration? What is the pH of the hydroponic solution and how does it affect nutrient uptake by the plant?
First Step – Source Water Analysis

Hydroponics solution consists of minerals in the source water and the nutrients added with fertilizers. The choice of fertilizers type and amount added greatly depend on the initial content of source water. Therefore, testing the source water prior to preparing a fertilizer formula is imperative.

For example, your source water may contain an sufficient amount of calcium for your crop nutrition. In this case, you should not use calcium nitrate, not only because it is redundant, but also because any calcium addition might precipitate with other elements in the hydroponic solution, such as phosphorus, or interfere with uptake of others.

Additionally, source water may contain too large amounts of harmful elements, such as sodium, chloride, fluoride or excess of boron, rendering it unsuitable for hydroponics. This can be solved by pre-treating the source water with desalination or ion-exchange.

Source water analysis must contain at least the following information:
EC, pH, calcium, magnesium, chloride, sodium, sulfur and bicarbonate levels.

If your water source is a bore hole/well, it would also be wise to test for boron, manganese and fluoride levels.

The Essential Plant Nutrients

There are 13 mineral nutrients that are essential for completion of the plant’s life cycle. Macro-elements are required in large quantities: nitrogen, potassium, phosphor, calcium, magnesium, sulfur. Micro-nutrients are required in very low concentration: iron, manganese, zinc, copper, molybdenum, boron, chlorine.

All of these nutrients should be provided in the hydroponics solution, in the right concentrations, and in adequate ratios.

According to the law of “limiting factor” , if one nutrient is deficient, other nutrients cannot compensate for the deficiency, and the crop may suffer, resulting in decreased quality and/or yield.

Nitrogen, phosphorus and potassium

Most water sources contain only very small amount of these nutrients, if at all, therefore they must be provided using fertilizers.

Commonly used soluble fertilizers are MAP, potassium sulfate, ammonium nitrate, potassium nitrate.

Calcium and magnesium

These elements are usually found in source water, sometimes in adequate concentration for our needs, especially in well-water. If the concentration is higher than required, the source water should be pre-treated.

Calcium nitrate is the only fertilizer appropriate for calcium addition to hydroponics irrigation water. Magnesium nitrate and magnesium sulfate are both appropriate sources for magnesium addition. Note that calcium nitrate and magnesium nitrate also contribute nitrogen to the solution.

Sulfur

Sulfur is present in a wide range of concentrations in various water sources, and plants growing in hydroponics can tolerate relatively high concentration. But sulfur excess might have untoward effects and even limit nitrate uptake.

Micro-nutrients

Iron, manganese, zinc and copper can be provided in the sulfuric form, but their availability is greatly decrease in pH greater than 6.5. The chelated forms, may also be used, because they are available for uptake in a wider range of pH. Some growers regard EDTA as harmful for plants, and avoid its use.

Molybdenum is usually provided using sodium molybdate. The presence of sodium in this fertilizer should not be a cause for alarm. Because molybdenum is needed in minute quantities, very small amounts of this fertilizer are usually used, and the sodium addition is negligible.

Boron can be provided through boric acid or solubor. Solubor also contains sodium, but again, quantities are small enough as to not have a significant effect on sodium concentration in the solution. Range for adequate boron levels is very narrow (0.2-0.5 ppm) and can easily be missed, resulting in either deficiency or toxicity. Therefore boron supplements should be carefully added. Well water often contain sufficient boron levels, so no boron addition is needed.

Harmful elements – Sodium – Chloride

Chloride is required by plants in minute quantities and most water sources contain chloride concentration well above and beyond plants require, so chloride deficiency is extremely rare. Chloride related problems are more commonly those of toxicities rather than of deficiencies. Therefore, using fertilizers which contain chloride is uncommon in hydroponics.

Sodium can be very harmful in recirculating systems, since it builds up with time in the hydroponic solution. Threshold concentration of sodium and chloride for most hydroponics grown plants is 75 ppm.

Electrical Conductivity (EC)

Electrical conductivity is a measure of the total salts dissolved in the solution (learn more about EC). It is used for monitoring daily applications fertilizers. Note that the EC reading doesn’t provide you with information regarding the ratios between nutrients.

In closed hydroponics systems, with recirculating solution, nutrients which are not absorbed by the plants (such as sodium, chloride, fluoride etc.) or ions released by the plant, build up in the hydroponic solution. In this case you need more information about the solution content, that EC cannot provide. Frequent water analysis tests will help you decide on the timing for replacing the nutrient solution or dilute it with good quality water.

pH

The optimal pH range for the nutrient solution is 5.8-6.3. micro-nutrients are more available in lower pH, but when pH levels drop below 5.5, you run the risk of micro-nutrients toxicity, as well as impaired availability of calcium and magnesium. In hydroponics, especially in closed systems, the roots readily affect the hydroponic solution pH, so pH tend to fluctuate.

Appropriate products for acidifying the hydroponic solution are sulfuric acid, phosphoric acid and nitric acid. The preferred one is sulfuric acid because the EC control and pH control are kept separate. This makes the grower’s job much easier.

Ammonium/nitrate is one of the major factors affecting the pH of the nutrient solution

Nutrient balance

Several nutrients compete with each other over uptake by the plant, so keeping adequate ratios is important for avoiding deficiency. For example excess of potassium compete with calcium and magnesium absorption. A high iron/manganese ratio can result in manganese deficiency, and high sulfur concentration might decrease the uptake of nitrate.

As mentioned in the beginning of this article, the nutrient balance in a closed hydroponics system changes frequently and has to be closely monitored and managed. Harmful minerals like sodium, chloride and fluoride build up in the solution and might reach toxic levels.

By: Guy Sela