An Introduction to Hydroponics

One of the greatest struggles when growing any plants is how much space is needed to effectively go from seed to harvest. Whether you’ve tried growing tomatoes in a pot, a full garden, or even just herbs, once you start to deal with soil, the plants themselves, and all of the various fertilizers, lights, and tools – it can become a bit overwhelming. Hydroponics simplifies the process down, using less space, reducing waste all while still producing healthy plants with amazing yields.

Hydroponics is a method of growing plants without the use of soil. The word originated in 1929 with Dr. Gericke, a California professor, based on the Greek words ‘hydro’ (water) and ‘ponos’ (labor). The method of growing was noted during World War 2 in providing food for troops who were stationed on desolate Pacific Islands. Ultimately it began to come into commercial use during the 1950’s.

At KindCare, our facilities grow cannabis using a hydroponic system. We’re able to fit more plants into a smaller space, vertically scale easier, and ultimately run a successful breeding program within our own warehouse. If you are considering growing your own cannabis, a hydroponic set-up may be an ideal method to consider.

The Pros and Cons of Hydroponics

There are a large number of pros to using a hydroponic system. Some of the most noteworthy are:

• Available anywhere regardless of climate or soil quality (e.g. dry desert areas or cold climate regions)
• Significantly higher crop yields
• No weeding, mess, or cultivation required
• Easier control over nutrient content, pH and growing environment
• Low water and nutrient costs due to redistribution of these elements
• May induce faster growth thanks to more available oxygen in the root area
• Greatly reduces the risk for most fungi, insect, and bacterial issues

In addition, some cons that should be considered are: the higher cost of initial set-up for a hydroponic system over that of a soil based system; the set-up and maintenance may have a higher learning curve; and some water-borne plant diseases may spread and threaten plants easier.

Types of Hydroponic Systems

Once you feel confident that a hydroponic system is right for your situation, you will need to decide which style you want to pursue. There are a wide variety with pros and cons to each. The two main systems are either Liquid or Aggregate.

Liquid Hydroponic System:

A liquid hydroponic system does not use any medium to hold the roots. Instead, they are fully exposed and periodically water or mist with nutrients is added. This provides the plant with all of the required elements needed to thrive.

Aggregate Hydroponic System:

An aggregate system utilizes a medium to support the roots. Some common mediums are rockwool, sand, and gravel. Water with nutrients is added to the system which allows the plants to thrive.

Both systems are very effective, but one of the simplest versions of a hydroponic system is utilizing a high-wick action aggregate and wicking delivery system. By utilizing wicking, there are fewer motors and electronics involved. The only electronic required for this is an air-pump with an air-stone.

Managing The Water

Hydroponics can have a steeper learning curve due to the multiple variables that need to be considered when managing the water itself. The key variables that should monitored are:

PH levels, which should be kept between 5.0 and 6.0.
EC levels, which should be kept between 1.5 to 3 dS m-1
Nutrients, which may vary for plants, but an example may be

Major Elements
Nitrogen (N) NO–3, NH+4 100 to 200
Phosphorus (P) HPO2-4 , H2PO–4 30 to 15
Potassium (K) K+ 100 to 200
Calcium (Ca) Ca2+ 200 to 300
Magnesium (Mg) Mg2+ 30 to 80
Sulfur (S) SO-24 70 to 150

Micronutrients
Boron (B) BO3- 30.03
Chlorine (Cl) Cl–
Copper (Cu) Cu2+ 0.01 to 0.10
Iron (Fe) Fe2+, Fe3+ 2 to 12
Manganese (Mn) Mn2+ 0.5 to 2.0
Molybdenum (Mo) Mo0–4 0.05
Zinc (Zn) Zn2+ 0.05 to 0.50

(Source: https://extension.okstate.edu/fact-sheets/hydroponics.html)

Maintaining high quality water is important for the success of your system and is why hydroponics may be considered more difficult to use and maintain than their soil-based counterparts.

Delivering the water to the plants can be accomplished in many ways. A pump can be run to either move the water across the roots or mist the water against the root system. Otherwise we can use a wicking system, gravity, or drip irrigation system. Each method of delivery changes the set-up slightly but offers their own advantages and disadvantages.

Shedding Some Light

The final component that is typically part of a hydroponic system are grow lights. Grow lights are not unique to hydroponics and are utilized in soil-based solutions as well, but significant care should be taken to ensure the lights utilized in your personal system are effective.

Some notable light wavelengths are 400-500nm (blue) and 620-740nm (red). Young cannabis plants utilize the blue light spectrum while flowering plants rely more on the red light spectrum. Due to this, it is common for hydroponic systems to utilize full spectrum lights as the primary light source.

A consideration can be made on the type of lighting you utilize. Fluorescent, LED, and incandescent are all options, however fluorescent and LED are the most common. Fluorescent lights offer a wide range of options and are often considered more cost effective to purchase. LED lighting however tends to require less energy to run.

A Simple Full System

While there are a large number of options in creating your own hydroponic system, we could describe one system from the top down as:

Lighting: Full Spectrum Fluorescent Grow Lights
Plant Container: A large container with perlite promote water wicking
Water Container: A large container with a wicking mechanism to the perlite. An air pump and air rock. Refilled daily to maintain water at proper levels.

This may be an over-simplification, however it demonstrates that starting your own hydroponic system doesn’t need to be an overly complicated process.

As you become more familiar with hydroponics, or if you are more adventurous in getting started, you could move to a water pump delivery method like a drip, ebb and flow system, or NFT system.

If you have any questions, our staff would love the opportunity to talk more in depth about the specifics you are considering for your own hydroponic system. In addition, KindCare offers seeds to get you started in your first cannabis growing experience!