So, what’s all the hype about hydro gardens? They seem to be the next big thing in growing but how much do you know? Maybe you have considered making the switch from soil to a hydroponic system but aren’t sure how. Lucky you! We’ve done the research, and have the experience so that you’re in the right place. Read up on the history, what, where, why, and how of hydroponic gardening here!
Hydroponic 101: Hydroponic gardening is a system to grow plants in a way that does not require soil. That’s right, no dirt. It can be used to provide a growing area in regions that do not have arable (farmable) land or to build large-scale gardens in a small amount of space. Hydroponic systems are often simple to assemble and allow for total control of nutrient levels. Hydroponic gardening enables you to design an environment to grow most anything- during any season, anywhere in the world.
One great advantage of growing with hydroponics is the expedited return on investment you see from your plants. Nutrients are delivered directly to the roots. This speeds up growth processes without sacrificing quality. You can increase the number of feedings without risking over-watering your plants. Another advantage is the reduction of fungi and bacteria often associated with soil. Pesticides are not often needed in a hydroponic system when temperature, humidity, and pH levels are carefully managed.
Disadvantages include cost and time investment. Hydroponic systems are time-intensive due to the daily pH level measurements, water temperature checks, nutrient management and pump maintenance. To get the most out of a hydroponic system, it must be treated as the science project that it is. With hydroponic growing, you are creating a synthetic environment for your plants. When playing the gardening god role, you must keep all of your elements in perfect harmony to avoid the imminent death of your crops. Just as fast as your plants benefit from direct contact with nutrient solutions to promote faster growth, deterioration can happen just as quickly when mismanaged.
So, why was hydroponic gardening invented? It allowed for farming and gardening in areas that were too arid or soilless. It also provided larger growing power in smaller spaces. The history and use of hydroponics go back before recorded history. One of the first recorded large-scale hydroponic gardens is also one of the world’s seven natural wonders, the Hanging Gardens of Babylon.
The Egyptians have hieroglyphs of growing soilless crops on the Nile, Marco Polo discovered the hanging gardens in China, and there are records of the Aztecs building floating garden rafts. The Aztecs piled nutrient-rich mud from the bottom of lakes on top of these rafts, then used them to grow vegetables and even trees! The Spaniards made notes about the unexpected sight of floating islands of trees and lush vegetables when they arrived. Minds blown!
In the 1600s, scientists began using hydroponic techniques to learn more about how plants grow, and what elements are needed for a plant to thrive. The first recorded scientific article was written by John Woodward in 1699. He was an English physician that set out to disprove the theory that plants were made up completely of water and could live on water alone. Woodward’s findings proved that plants grown in pure spring water did not grow as fast as those that were grown with dissolved substances from the Thames river, rainwater, or soil. Following these studies, scientists came to understand the biology of plants and continued their research.
German scientists in the 1860s, Knop and Sachs, laid the foundation for many of the hydroponic nutrient recipes we use in our grows today. They discovered macro and micro elements needed for plants' health and growth. The meaning of the name given to this style of gardening is Hydro, from the Greek word meaning water, and ponos meaning labor. The work of water and the experiments of those before us have gifted us with the wonderful world of hydroponic gardening!
Artificial Environment Components
High-powered lights are used to replace the natural sunlight received by plants outdoors. The use of indoor grow lights allows you, the goddess of your grow, to dictate the amount of “daylight” hours your plants receive, as well as regulate the quantity and quality of their light. Alternatively, you can operate a hydroponic system with natural sunlight indoors, in a sunroom or greenhouse. However, hydroponic systems are designed for being used in climate-controlled areas. Keep in mind, that it is easier to manage temperature indoors in an enclosed area.
To simulate the breeze and movement of air, the strategic placement of fans is needed for a successful grow. Plants use the CO2 that surrounds them quickly. Thus, the air within proximity of the plants needs to be replaced with fresh air at regular intervals. This also keeps the air from stratifying by breaking up layers of heat that are overly oxygenated, or CO2-rich atmosphere layers. Install an intake fan near the floor of your grow room to bring in fresh air. Place an exhaust fan near the highest point of your grow room to pull air from the hottest part of the room.
The movement of air, with the help of the oscillating fans, will mimic the movement of air outdoors. Fans are also helpful for temperature regulation. Most plants thrive between 60-80 degrees Fahrenheit. Any higher or lower may stress the plants and prevent them from producing the highest quality product.
A plant’s root system is very sensitive to stress. To provide a consistent, temperature-controlled environment, it may be necessary to implement a water heater or water chilling unit for your grow. We would recommend a titanium water heater over a glass heat for safety and practicality. The nutrient solution given to your plants must be stored and fed to your plants at the same temperature that the system is running at. Your goal should be to keep the root system temperature at or around 72 degrees, allowing temps to dip to as low as 60 degrees during dormant (nighttime) hours. If you are using a pump, remember that it tends to warm the water. You may want to counteract the pump's heat by using a water chiller. We prefer the Active Aqua air pump as they are consistent and affordable.
Since hydroponics does not use soil, it lacks many nutrients that are typically held in the soil. This means you are going to need to supplement these much-needed nutrients in a water-soluble solution. When selecting nutrient solutions, make sure to check that they contain boron, calcium, copper, magnesium, nitrogen, phosphorous, potassium, silica, sulfur, and zinc. There are several products to choose from but our favorite nutrient lines for hydroponics include HGV, Canna, and Athena. At the very least, you must replace what is being lost in the absence of soil, but a solid nutrient solution will help ensure rapid development and healthy production. Synthetic nutrients are not plant-specific. They contain all elements essential to plant growth but may need to be given in different dosages depending on what you are growing.
Other formulas may be best suited for your grow. For example, for more vigorous plants such as tomatoes, adding a silica-rich solution will give them the strength to hold themselves upright without the help of stakes or trellises. In addition to nutrient solutions, indoor growers should also consider adding supplemental CO2 to the growing atmosphere. When growing indoors, you can accelerate growth even more by implementing a CO2 regime during daylight hours. Providing higher levels of CO2, allows the plants to speed up their metabolic processes.
The pH measurement runs on a scale from 1 to 14 and measures the acid-to-alkaline balance. One is the most acidic, seven is neutral, and 14 is the most alkaline (basic). Every full point on the pH scale indicates a 10-fold increase or decrease in alkalinity or acidity. This is very important to understand. A drop of water that reads at a pH of six is TEN TIMES more acidic than a drop of water reading at a pH of seven. Assuming you’re great at math, then you already know that water with a pH reading of five is a HUNDRED TIMES more acidic than a water pH of seven.
Make sure you pay close attention to your pH levels and read them at least once a day to make sure your system is in balance. If a solution is too acidic you run the risk of salt burn. If your solution is too basic, can severely limit nutrient availability. Most plants thrive between a pH of 5.5 and 6.5. If pH levels sway by half a point outside this range, don’t worry too much, but this is a warning that something is off. Make sure you investigate what could be throwing your pH off. Anything more than half a point is cause for concern and immediate action. Make sure you adjust the pH up or down accordingly. One of our favorites is General Hydroponics or Remix as a pH up. If you are looking to adjust your pH down, you may want to reevaluate your nutrient solution. If you have made this evaluation and still need to pH down, we also recommend General Hydroponics or Remix pH down. The plants absorb more elements at different pH levels within the nutrient solution. So make sure you see a healthy swing between the optimum pH levels of 5.5 and 6.5.
How Do I Get Started?
There are several different setups to choose from. It depends on your personal preference of which factors you feel like focusing your energy on. Read on to explore your different growing options when using hydroponics to get the most out of your grow.
Deep Water Culture
Deep water culture, or the reservoir method, is the easiest of all the methods of growing hydroponically. In this system, the roots of the plants are suspended in a nutrient-rich water bath. A pump, similar to what you would use in an aquarium, is used to bring oxygen to the root system of your plants to prevent them from “drowning” in the bath. Water is the way of delivering nutrients to plants. Make sure you are not feeding your plants with chlorine-rich, nutrient-stripped water (i.e. tap water) if you are expecting to see a fruitful crop. We are going to go out on a limb here and assume you do want a decent yield, so make sure you are utilizing a water filtration system such as the HydroLogic Evolution RO system to filter out sediment, heavy metals, and certain water-borne pathogens.
Nutrient Film Technique (NFT)
The nutrient film technique is built on a system that is situated at a tilt. A pump ejects nutrient water to the highest point and gravity feeds it back into a pool at the end of the growing table. The water is continually being pumped and again fed through the root system. This way, there is a continual flow of solution that moves over the top of the root systems of the plants. This system does not require an oxygen-providing pump because just the tips of the roots are exposed to the fluid. The rest of the root is exposed and available to receive the available oxygen in the room.
Ebb and Flow/Flood and Drain
Ebb and flow systems are the most common for beginning hydroponic growers. Typically, you will have your plant roots placed in a reservoir that would be flooded with your nutrient-rich solution according to an automated timer. The reservoir is then drained, providing a resting period for the plants, and then again flooded on demand of the timer. The danger of this system is in relying on a timer and pump to provide nutrients for the plants. If the pump fails, so do you. The ebb and flow work well with plants that benefit from short dry spells and that can survive up to ten hours without getting water if the pump goes out such as tomatoes and gardens.
Drip systems deliver nutrients in small amounts continuously throughout the day. It works best when paired with a material, such as Coco Coir, Rockwool, or Hydroton. These will absorb the nutrient-rich water, and support the root systems. We recommend Netafim and FloraFlex components for attaching your water pump. For a hassle-free, prefabricated hydroponic drip system we like the ExoTower Hydroponic Garden Tower. This dirt-free gardening method is ideal especially if you are wanting to grow indoors.
Aeroponics is another method of using hydroponic growing methods. In aeroponics, the root systems are suspended in the air to be frequently misted by a nutrient-rich solution. Just like in drip systems, if the pump goes out in this system you’re screwed. A typical aeroponic setup consists of gutter-type trays that hold several 3-inch mesh pots. The roots grow outside the pots and reside in the open air. A line of PVC pipe with misters is placed in direct proximity to the root zone to administer the nutrient solution. The misters are fed by a pump that pulls from a reservoir of solution. Make sure your pump is set on a timer to water for 1-3 minutes on and five minutes off. Watering is only needed when the lights are on with this method, with the option to set your timer to administer one or two short sprays during dormant hours to keep the roots moist.
Hydroponic mediums serve as an anchor for the plants and aid in moisture retention. When choosing a growing medium, you will want to choose one that compliments the hydroponic system that you have chosen to implement. Different types of substrates each have beneficial qualities to consider. There are three main types—Rockwool, expanded clay aggregates, and Growstones.
The most popular of the available growing mediums is Rockwool. Rockwool is a volcanic rock that is spun into thin fibers. It is made from the same type of rock, molten basalt, that is often spread on icy roads in the winter. It is lightweight and very porous. When shaped into cubes or blocks it provides a great environment for water and nutrients to flow through. Rockwool is sterile out of its original packaging.
Lightweight clay aggregates are formed into small balls that are fired in a kiln. They resemble a honeycomb in structure. Clay aggregate pebbles have dozens of tiny holes that are useful for storing and providing oxygen, moisture, and nutrients to your plants after flooding stages used in systems like the ebb and flow. A major benefit is that clay aggregate can be sterilized and reused multiple times.
Growstones are made from recycled glass and are largely popular in the green growing community. They are beneficial in use for airflow and are said to have up to three times the amount of water storage than clay aggregate (which can be a positive depending on your growing system). Due to their shape, they provide large porous gaps to allow for adequate airflow and oxygen intake. The larger gaps also provide more space for roots to take hold and thus create a more stable root environment.
Soilless mediums can be mixed and matched to create the perfect balance of porosity and nutrient delivery needed for your grow.
When building up your hydroponic system there are a few items to consider:
- Choose a plastic that is UV resistant and won’t break down over time.
- If repurposing materials, make sure there are no residual materials from their previous use that may cause harm to your plants.
- Don’t use any materials that you wouldn’t yourself drink water from.
- If using silicon, seal your joints so you don’t poison your plants.
- Put a cover on your solution reservoir to avoid evaporation of product and money.
- Build-in an anchor system for your plants so your plants won’t fall over.
- Waterproofing your power sources is a key preventive safety measure.
- Managing your pH will make or break you.
The more you know, the better you grow
Growing with hydroponics is a great way to take complete control over your growing system. It also enables you to create an automated system that requires less time from you as a grower. Your plants also benefit from soilless mediums because it removes potential bacteria and fungi that reside in soil-based systems.
Many growers see their grows as an art form that they can calibrate and adjust to get the most out of their plants and hydro lets you do just that. With the number of growing mediums to choose from, nutrients and flow systems to mix and match—you can create a unique system, unlike any others.