Guide to Commercial Hydroponic Greenhouses

What is Hydroponics?

Simply put, hydroponics is a form of agriculture used in commercial hydroponic greenhouses where soil is replaced by a constant feed of nutrient solution, sometimes with a porous growing media. The adoption of hydroponic systems in the cannabis cultivation industry is a line steadily traveling upwards—not least because it results in healthier, nutritionally superior crops. Read this guide for the different types of commercial hydroponic greenhouses and decide which best suits your venture.

How Do Commercial Hydroponic Greenhouses Work?

Hydroponics tackles the base concern of agriculture: giving your plants what they need when they need it. A hydroponic greenhouse gives you minute control over environmental factors such as pH balance and exposure to water and specific nutrients.

There are currently seven types of hydroponic growing systems in the market. Each type is made up of different tools and equipment that facilitate different soilless methods in achieving one goal: successful maximum yields. Each is either active and functions by pumping or moving the nutrient solutions, or passive and relies on wicks or anchors of the growing media.

Another further classification is recovery and non-recovery, referring to whether excess water in the medium is routed to flow back for reuse, or be run off as waste. Some setups work by anchoring plants with an inert growing media into their containers, others expose plant roots in water or air without any media.

Types of Hydroponic Systems

Nutrient Film Technique (NFT) is an active, recovery hydroponic system that uses water pumps to move nutrient solution into channels that hold various amounts of plants typically suspended by foam net pot inserts. The channels are tilted so that nutrient flows in a shallow stream over the ends of exposed roots—like a film—and back into the reservoir. Grooves in the floor of the channels prevent pooling or damming. This system works best for lightweight plants with a small root system and is a go-to for commercial growers due to ease of multiple plant growing and mass production.

Deep Water Culture (DWC) suspends the roots of growing plants in nutrient solution aerated by a diffuser or air stone. Net pots with grow medium secure the plants over a deep reservoir (also known as a bubble bucket), and a circulation pump connected to the air stone ensures that your plants don’t drown in the constant nutrient solution. This is the kind of hydroponic greenhouse you’d see used for pepper plants, for example, as it specializes in large plants with big root systems or abundant fruit.

Wick Hydroponics is the most passive and simplest of hydroponic growing; it uses no pumps, aerators, or electricity. Typically, plants are placed on a tray of growing medium on top of a reservoir filled with water and dissolved nutrients. Nylon wicks absorb the solution and transfers the nutrients through the porous growing media around the root system of the plants. The best material for the media is coco coir, vermiculite, or perlite because of how well they transfer both water and nutrients. This is a cost effective method for both commercial and hobby growers.

Ebb & Flow, also known as Flood & Drain is an active, recovery method used by many home hydroponic gardeners or smaller greenhouse growers. Plants are situated on large grow beds filled with growing medium, above a reservoir that periodically floods the grow bed with nutrient solution. It’s a very controlled environment; the system is equipped with a timer and overflow tube to avoid over-flooding. This system does not constantly expose plants to water supply. When the roots dry out, oxygenation happens — the process of flooding and oxygenation can be experimented with to grow high quality produce.

Drip Hydroponics is a good choice for an existing greenhouse that intends to experiment and make constant changes. An aerated reservoir pumps nutrient solution through a network of tubes, from which it is dripped gradually into growing media around the root system of individual plants. A drip irrigation system could be configured to be recovery or non-recovery. In highly conservative drip systems, non-recovery is in fact a fair option and popular in larger commercial growing systems that utilize timers to carefully control water flow and nutrient waste.

Aeroponics is an active process of using nutrient mist to feed the exposed root system of suspended plants. Typically structured as towers, an enclosed framework is used to house many plants at once. Of all the growing systems, aeroponics use the least amount of water and grows the fastest due to the high exposure to oxygen. It enables simple, year-round harvesting and works for any plant except those with larger and heavier root systems.

Dutch Buckets, also known as Bato Bucket, is an active recovery system where two or more growing containers are connected to the same irrigation and drainage lines. A pump sends the nutrient water up irrigation, where it flows out of drip emitters into the growing media within each bucket of potted plants. The excess is drained and brought by the drainage line back to the reservoir.

Advantages Of Growing in Commercial Hydroponic Greenhouses

Cultivation in a commercial hydroponic greenhouse eliminates the health risk of pesticides and artificial ripening agents that are used in irrigated fields, due to the lower risks of pests or weeds. This means that your crops are going to turn out healthy, high quality produce.

Plants grown hydroponically are also 30% to 50% faster2 than those grown in soil; the controlled environment allows the perfect amount of nutrients and a distinct lack of environmental stressors like unconducive weather conditions. This also helps with producing bigger yields.

While field farms account for 80% of the United States’ water usage3, hydroponic growing systems use about 10 times less water4. Not to mention, you save space on individual crops because roots don’t need to spread to reach the required water and nutrients; it’s fed straight to them. Read more about commercial greenhouse farming.

How to Create a Hydroponic System

The first decision to be made is which hydroponic system you are best suited to use. Consider the available space you have, including the exact measurements and potential space divisions for your greenhouse. How much sunlight would get through? Do you need to invest in artificial grow lights? Where is your hydroponic power supply coming from — a reliable source of electricity is needed for the pumps and lights. Last but certainly not least, consider the source of your constant water supply.

What Does a Hydroponic System Need?

Whichever method you decide on, you can start planning your commercial hydroponic greenhouse with Prospiant: your one-stop source of growing green. Build your greenhouse tailored for the ideal conditions, from new production automation to LED grow strategies and nutrient-rich water. Our experts are ready to help you, from temperature systems and irrigation systems to CO2 systems, and water storage. It’s all at your fingertips—Prospiant is here to reliably provide as your partner in growth.

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