Disclaimer: None of the information in this article constitutes medical advice, and is just the opinion of the writer(s). We recommend that patients follow their doctor’s guidance in regard to cannabis use, and follow the laws of their local jurisdiction(s).

There are an increasing number of hydroponic cannabis brands, but not much research comparing the health effects of hydroponically-grown weed to conventionally-grown weed. Some hydroponic weed companies suggest that their products are higher quality than weed grown outdoors.

But what even is hydroponic weed, and how is it grown? Is hydroponic weed healthier than weed grown outdoors? What questions should consumers ask their weed grower? And how does the cost of hydroponic weed compare to the cost of weed grown outdoors?

In this article we’ll answer all of these questions and more, as we explain what hydroponic weed is and how it's grown.

We'll share our thoughts on whether or not hydroponic weed is healthier than weed grown outdoors, feature a video that discusses the relative costs, and provide some questions that consumers may wish to ask their weed grower in jurisdictions where weed is legally available for purchase.

What Is Hydroponic Weed?

Hydroponics is a type of technology that allows for growing plants without soil. Cannabis is a plant traditionally grown in soil, and growing it hydroponically can make the process more efficient and climate-resistant.

Many grow operations prefer hydroponic weed to traditional methods because it’s possible to automate the process to a level of precision not possible with outdoor farming. 

Using hydroponics, a cannabis grower can set nutrient inputs, optimize light exposure, and generally refine every parameter of the grow process for maximal efficiency.

When growing weed outdoors, growers have to simply let nature take its course.

Hydroponic weed is different from greenhouse weed, although both are typically grown indoors. A greenhouse allows growers to manage certain external conditions like sunlight and water, but most greenhouse grow operations still use soil and are still considered traditional agriculture.

A YouTube video from the "Marijuana SA" channel tours one of the largest legal hydroponic weed facilities in South Africa, and shows how it's grown indoors:

Is Hydroponic Weed Healthier?

There is unfortunately little research directly comparing the health effects of hydroponically-grown weed to conventionally-grown weed.

We believe that hydroponic weed is likely to be healthier for two reasons:

Reason 1 — No Pesticides

Many hydroponic cannabis operations are pesticide-free. Since the environment is tightly controlled, the risk of pests destroying crops is much lower, so many operations do not use pesticides.

We know from years of medical research that pesticide ingestion is harmful for human health. This risk is even greater for plants which are smoked like cannabis, since the pesticides are inhaled directly into the lungs.

Reason 2 — Lower Levels of Heavy Metals 

Plants can absorb heavy metals like lead, mercury and cadmium from polluted soil.

These metals are toxic to humans, and are unfortunately present in many foods and supplements due to their pervasive nature in our environment, so minimizing their exposure is important for health.

Since hydroponic weed is grown in a soil-free environment, we consider it less likely to be contaminated with heavy metals.

A 2021 clinical trial found that hydroponically-grown tomatoes were "higher quality" than conventionally-grown tomatoes, in part due to the factors described above.

What Should I Ask My Grower?

Health conscious weed users may want to directly ask their grower or dispensary whether they sell hydroponic weed, and ask whether the hydroponic weed is free of pesticides and heavy metals.

Just because hydroponic cannabis operations may be less likely to contain these contaminants doesn’t mean none do, so asking for proof seems like a good idea.

It may also be beneficial to ask about the tetrahydrocannabinol (THC) content, since this is the psychoactive compound in cannabis and its potency may vary dramatically between hydroponically-grown and conventionally-grown weed.

Environmentally-conscious consumers may wish to ask their weed grower about water inputs, and how much water a hydroponic system saves compared to traditional grow operations.

Hydroponic vs. Traditional Weed

A YouTube creator named "The Cannabis Experts" has a video on the relative benefits of hydroponically-grown weed versus soil-grown weed with over 80,000 views:

Conclusion

We consider hydroponic weed to be healthier than soil-grown weed, due to the likely lower levels of pesticides and heavy metals. These are the most common cannabis contaminants, and are harmful to human health.

While we can't find any clinical studies directly testing the health effects of hydroponic weed versus traditionally-grown weed, a recent clinical trial found that hydroponically-grown tomatoes were of higher quality than outdoor-grown tomatoes, which may support our hypothesis.

As we mentioned in our article on weed and heart attacks, the inhaled toxins from smoking may be the cause of the slightly increased cardiovascular risk associated with cannabis use, rather than the cannabis itself.

This theory makes toxin mitigation via hydroponic sourcing even more vital.

Consumers may wish to ask their weed grower about whether the weed is grown hydroponically, and whether pesticides and heavy metals are tested for, prior to making a purchase.