Hydroponic System

Hydroponics is the art of gardening without soil. Hydroponics is a Latin word meaning “working water.” In the absence of soil, water goes to work providing nutrients, hydration, and oxygen to plant life. From watermelons to jalapeños to orchids, plants flourish under the careful regimen of hydroponics. Using minimal space, 90% less water than traditional agriculture, and ingenious design, hydroponic gardens grow beautiful fruits and flowers in half the time.

Though the technology sounds cutting-edge, the history of hydroponics dates back to the famed Hanging Gardens of Babylon, one of the Seven Wonders of the Ancient World. The Euphrates River was diverted into channels that cascaded down the lavish garden walls. In the 13th century, Marco Polo wrote of witnessing floating gardens in China. However, hydroponics is far from merely an innovation of the ancient ages. In the 1990s, NASA grew aeroponic bean seedlings in zero gravity aboard a space station, opening up the possibility of sustainable agriculture in space. Hydroponics continues to be a timeless and dynamic method of water conservation and crop production.

What is hydroponics?
Hydroponics is the cultivation of plants without using soil. Hydroponic flowers, herbs, and vegetables are planted in inert growing media and supplied with nutrient-rich solutions, oxygen, and water. This system fosters rapid growth, stronger yields, and superior quality. When a plant is grown in soil, its roots are perpetually searching for the necessary nutrition to support the plant. If a plant’s root system is exposed directly to water and nutrition, the plant does not have to exert any energy in sustaining itself. The energy the roots would have expended acquiring food and water can be redirected into the plant’s maturation. As a result, leaf growth flourishes as does the blooming of fruits and flowers.

Plants sustain themselves by a process called photosynthesis. Plants capture sunlight with chlorophyll (a green pigment present in their leaves). They use the light’s energy to split water molecules they’ve absorbed via their root system. The hydrogen molecules combine with carbon dioxide to produce carbohydrates, which plants use to nourish themselves. Oxygen is then released into the atmosphere, a crucial factor in preserving our planet’s habitability. Plants do not need soil to photosynthesize. They need the soil to supply them with water and nutrients. When nutrients are dissolved in water they can be applied directly to the plant’s root system by flooding, misting, or immersion. Hydroponic innovations have proven direct exposure to nutrient-filled water can be a more effective and versatile method of growth than traditional irrigation.

How does hydroponics work?
Hydroponic systems work by allowing minute control over environmental conditions like temperature and pH balance and maximized exposure to nutrients and water. Hydroponics operates under a very simple principle: provide plants exactly what they need when they need it. Hydroponics administer nutrient solutions tailored to the needs of the particular plant being grown. They allow you to control exactly how much light the plants receive and for how long. pH levels can be monitored and adjusted. In a highly customized and controlled environment, plant growth accelerates.

By controlling the environment of the plant, many risk factors are reduced. Plants grown in gardens and fields are introduced to a host of variables that negatively impact their health and growth. Fungus in the soil can spread diseases to plants. Wildlife like rabbits can plunder ripening vegetables from your garden. Pests like locusts can descend on crops and obliterate them in an afternoon. Hydroponic systems end the unpredictability of growing plants outdoors and in the earth. Without the mechanical resistance of the soil, seedlings can mature much faster. By eliminating pesticides, hydroponics produce much healthier and high-quality fruits and vegetables. Without obstacles, plants are free to grow vigorously and rapidly.

What are the components of a hydroponic system?
To maintain a flourishing hydroponic system, you will need to become acquainted with a few components that make hydroponics run efficiently.

Growing media
Hydroponic plants are often grown in inert media that support the plant’s weight and anchor its root structure. Growing media is the substitute for soil, however, it does not provide any independent nutrition to the plant. Instead, this porous media retains moisture and nutrients from the nutrient solution which it then delivers to the plant. Many growing media are also pH-neutral, so they will not upset the balance of your nutrient solution. There are a host of different media to choose from, and the specific plant and hydroponic system will dictate which media best suits your endeavor. Hydroponic growing media is widely available both online and at local nurseries and gardening stores.

Air stones and air pumps
Plants that are submerged in water can quickly drown if the water is not sufficiently aerated. Air stones disperse tiny bubbles of dissolved oxygen throughout your nutrient solution reservoir. These bubbles also help evenly distribute the dissolved nutrients in the solution. Air stones do not generate oxygen on their own. They need to be attached to an external air pump via opaque food grade plastic tubing (the opacity will prevent algae growth from setting in). Air stones and air pumps are popular aquarium components and can be purchased easily at pet stores.

Net pots
Net pots are mesh planters that hold hydroponic plants. The latticed material allows roots to grow out of the sides and bottom of the pot, giving greater exposure to oxygen and nutrients. Net pots also provide superior drainage compared to traditional clay or plastic pots.

There are hundreds of hydroponic methods, but all of them are a modification or combination of six basic hydroponic systems.

1. Deep water culture systems
Deep water culture hydroponics are simply plants suspended in aerated water. Deep water culture systems, also known as a DWC system, are one of the easiest and most popular methods of hydroponics on the market. A DWC system dangles net pots holding plants over a deep reservoir of oxygen-rich nutrient solution. The plant’s roots are submerged in the solution, providing it with perpetual access to nutrition, water, and oxygen. Deep water culture is considered by some to be the purest form of hydroponics.

Since the root system is suspended in water at all times, proper water oxygenation is vital to the plant’s survival. If there is not enough oxygen supplied to the plant’s roots, the plant will drown in the solution. Add an air stone connected to an air pump at the bottom of the reservoir to supply oxygenation to the entire system. The bubbles from the air stone will also help circulate the nutrient solution.

It is very easy to assemble a deep water culture system at home or in a classroom without needing expensive hydroponics equipment. You can use a clean bucket or old aquarium to hold the solution and place a floating surface like styrofoam on top to house the net pots. Plants in DWC systems should only have their roots submerged in the solution. No part of the stem or vegetation should be underwater. You can even leave about an inch and a half of the roots above the waterline. The air stone bubbles will pop out of the surface and splash onto the exposed roots, so they will not be at risk of drying out.

What are the advantages of deep water culture systems?
Low maintenance: Once a DWC system is set up, there’s very little maintenance required. Just replenish the nutrient solution when needed and make sure your pump is running oxygen to the air stone. The nutrient solution typically only needs replenishing every 2-3 weeks, but this does depend on the size of your plants.
DIY appeal: Unlike many hydroponic systems, deep water culture systems can be made cheaply and easily at home, with a quick run to your pet store and local nursery to pick up the air pump and nutrients.
What are the disadvantages of deep water culture systems?
Limitations: Deep water culture systems are adept at growing herbs and lettuce but they struggle with larger and more slow-growing plants. DWC systems are not ideal for anything that flowers. However, with some extra work, you can grow plants like tomatoes, bell peppers, and squash in a DWC system.
Temperature control: It’s important that your water solution does not exceed 68°F and does not go below 60°F. In a DWC system, the water is static and not recirculating, so it can be more difficult to regulate temperature.
2. Wick systems
In a wick system, plants are nestled in growing media on a tray that sits on top of a reservoir. This reservoir houses a water solution with dissolved nutrients. Wicks travel from the reservoir to the growing tray. Water and nutrients flow up the wick and saturate the growing media around the root systems of the plants. These wicks can be made of material as simple as rope, string, or felt. Wick systems are by far the most simple form of hydroponics. Wick systems are passive hydroponics – meaning they don’t require mechanical parts like pumps to function. This makes it ideal for situations where electricity is either unreliable or unavailable.

Wicks systems work by a process called capillary action. The wick absorbs the water it’s immersed in like a sponge, and when it comes in contact with the porous growing media, it transfers the nutrient solution. Wick system hydroponics only work if accompanied by growing media that is able to facilitate nutrient and water transference. Coco coir (fibers from the outer husks of coconuts) have excellent moisture retention and the added benefit of being pH neutral. Perlite is also pH neutral and extremely porous, making it ideal for wicking systems. Vermiculite is also very porous, and also possesses a high cation-exchange capacity. This means it can store nutrients for later use. These three growing media are the most suitable for hydroponic wick systems.

Wick systems work quite slowly compared to other hydroponic systems, which does limit what is practical to grow with them. You’ll want to make sure for every plant in the growing tray you have at least one wick running from the reservoir. These wicks should be placed close to the root system of the plant. Though capable of functioning with aeration, many people do choose to add an air stone and air pump to the wick system’s reservoir. This adds extra oxygenation to the hydroponic system.