Growing Organic vs. Chemical Cannabis Fertilizers for Your Grow Trevor Hennings December 6, 2016

Cannabis plants are resilient and resourceful. However, much like any other living organism, cannabis plants need nutrients. Also known as fertilizers, nutrients can be either organic or inorganic (chemical).

Before chemical fertilizers, traditional farming practices required you to keep the soil healthy and rich in nutrients by either using nitrogen fixers such as leguminous plants (e.g. beans, peas) as cover crops or by spreading manure. These were the basic methods used for centuries to keep gardens productive.

Then along came a new style of modern day farming. It was shaped in 1840 with a publication, Chemistry in Its Application to Agriculture and Physiology, by Justus Von Liebig. This book introduced the concept of N-P-K (Nitrogen, Phosphorus, and Potassium) as the essential nutrients needed for a healthy plant. However, creating these nutrients chemically was costly, especially nitrogen.

This all changed at the start of the 20th century due to a discovery made by Fritz Haber. Fritz figured out how to fix nitrogen from the air and then combine it with hydrogen pulled from natural gases to create ammonia. Ammonia then could be produced and used as a nitrogen fertilizer at a very low cost.

Today, there is continual debate around which type of fertilizer is the right choice for your cannabis plants. Both methods can produce quality product, but they each have disadvantages to consider as well.

Organic Cannabis Fertilizers



Organic fertilizers are described as nutrients that come from organic sources such as animal and vegetable waste. They also extend to sediments like glacial rock dust and gypsum that contain beneficial minerals for the soil and plant.

The benefits of organic fertilizers:

Slow release of nutrients protects the plants from overfeeding/burning

Overtime organic fertilizers can improve the quality and diversity of life in your soil

Improved airflow and water retention in soil

Renewable and sustainable

Organics stay in the soil with a lower chance of nutrient run-off

When working with organic fertilizers, you are given the opportunity to improve your growing medium while at the same time improving the quality of your flowers. The benefit from organics largely comes from the ability to nurture this balance. Growers often find that growing organically increases the flavor profile of the cannabis as well as the yield.

Another substantial benefit comes from the fact that this fertilization process can repeat itself year after year as the soil continually improves. This makes using organic fertilizers a popular choice for outdoor gardeners who use the same soil repeatedly. Using organics is also preferred for those who want to be more aware and in tune with their natural environment. Organic fertilizers are readily available from renewable sources, and when applied, they ground down in the medium, preventing nutrient run-off and thus making organic fertilizers the earth-friendly option.

The disadvantages of organic fertilizers:

Take time to be absorbed by the plant

Require microorganisms to break down the nutrients which may slow in colder temperatures

Can introduce insects and pests

Costly

There are complications and difficulties that come from working with organic fertilizers. For example, when faced with a nutrient deficiency in the middle of flowering, adding nutrients from organic fertilizers might not work as quickly as desired, leaving the plants damaged. Also, organic fertilizers can sometimes introduce pests into your garden which can be difficult to handle, especially indoors.

Chemical Cannabis Fertilizers

Chemical fertilizers are synthesized and extracted to a specific chemical form. The nitrogen comes from the aforementioned Haber-Bosch process. Phosphate and potassium are extracted from minerals, and other impurities that can harm the plants are removed. The results of these extractions are highly refined specific quantities of N-P-K nutrients.

The benefits of chemical fertilizers:

Exact nutrient ratios

Increased growth and THC production

Rapid nutrient uptake

Affordable and widely available

The main benefit of using chemical fertilizers lies in their precise ratios of nutrients that can deliver big results in terms of yield. When applied to your garden, they are readily available and can start to impact a plant’s health immediately. The specific ratios of different fertilizers allow you to customize what works best for individual strains, leading to higher yields and THC contents.

The disadvantages of chemical fertilizers:

Do not feed into the development of the soil

Can burn and kill plants by overfeeding

Leech from growing medium, impacting surrounding environment

Produced from non-renewable resources

Chemical fertilizers do have downsides. Because the nutrients are readily available, they can also burn and kill a plant by overfeeding. Also, these readily available nutrients do not add to the quality of soil before being used by the plant, leaving the soil quality diminished. Weakened soil quality allows for nutrient run-off to occur, which wastes nutrients and can negatively impact the surrounding environment.

Lastly, these chemical fertilizers are not produced by renewable resources. Producing nitrogen is an energy intensive process that takes a toll on the environment especially as climate change and environmental issues become more pressing than ever before.

Other Considerations

A good analogy for organic and chemical fertilizers is the comparison between baking and cooking. Organics are like cooking. You can take away, add, and alter the recipe and find a unique delicious meal at the end of the day. Chemical fertilizers are like baking. You know what you have, and if you know what you precisely need you will end up with a beautiful loaf of bread. If you stray from the recipe, however, problems will arise.

Of course, the goal of any gardener is to produce the highest quality product, but it should be noted that as cannabis production increases in scale, there’s more room for nutrient run-off, environmental impacts, and resource depletion. Thankfully, the cannabis community has a lot of forward-thinking individuals, and as the industry continues to develop, there’s a lot of opportunity to look at what can be done to make this crop as sustainable as possible.

Trevor Hennings Trevor is a freelance writer and photographer. He has spent years in California working in the cannabis industry. View Trevor Hennings's articles