Do I Qualify?

Make an Appointment

Content Hub


Find a Dispensary Read Articles


Applying for your medical marijuana card is easier than ever. Just book an appointment. Talk to a doctor. And get your card. Bing. Bam. Boom.

Marijuana Doctors

Get your medical marijuana card

Cannabis Consultation

One on one with a cannabis coach

Patient Login

Sign in to your Veriheal patient account

Guides, Research

What Is PGR Weed and How Do You Spot It?

Chane Leigh

by Chane Leigh

July 23, 2024 08:00 am ET Estimated Read Time: 9 Minutes
Fact checked by Kymberly Drapcho Medically reviewed by Dr. Carlie Bell
What Is PGR Weed and How Do You Spot It?

​With PGR weed growing in popularity, staying safe is the highest priority.

PGR weed is grown with plant growth regulators to produce higher yields and fatter nugs. However, these potential benefits come at the risk of compromising flavor, visual appearance, and more extreme health effects. 

What is PGR Weed?

PGR weed is cannabis flower grown with plant growth regulators to boost yield and nug size. PGRs, or Plant Growth Regulators, are any substances, fertilizers, or mixtures that can be used to speed up or slow down the growth rate in plants and food crops by targeting physiological actions that then change the natural behavior of the plant. The main function of PGRs is to mimic or inhibit the plant’s normal growth hormones during the growth cycles. 

PGRs can have an impact on when fruits ripen and also on the length, width, and shape of the plant’s roots, stems, trichomes, and leaves. It’s time consumers start asking the right questions to ensure not only the best value for their money but, more importantly, to minimize health risks.

For cannabis, PGRs are likely commonly used to increase the plant’s health and resistance to fungus but often at a cost of flavor and visual appearance. More extreme risks of PGR cannabis include risks of organ damage, cancer, and infertility. They can also cause more minor health effects, like skin or eye irritation.

Types of Synthetic PGRs Used While Growing Weed

When you see the words synthetic before anything, you should already be approaching with caution. Synthetic means that it was man-made using chemicals, compounds, or materials that imitate natural products for human consumption. If we have learned anything at all about the difference between synthetic and organic products is that the synthetic versions are often accompanied by less effective as well as adverse or undesired side effects. With that in mind, let’s have a look at some of the synthetic PGRs on the market:

  • Paclobutrazol
  • Daminozide
  • Chlormequat Chloride
  • In a not-so-unexpected shift of events, these synthetic PGRs are bad for our environment. Additionally, the Environmental Protection Agency (EPA) recently identified daminozide as a probable carcinogen.

The residual PGRs in the soil and water can cause some serious damage to the fish and waterways. Additionally, growing cannabis has been known to boost biodiversity in the soil but when synthetic plant growth regulators are used, biodiversity becomes negatively impacted.

Regulatory Status of PGRs

  • Discuss the legal status and regulatory concerns regarding these chemicals, including bans and health warnings.

Impact on Cannabis

How is it that PGRs can have such an impact on buds? Well, simply put, the PGRs have an impact on the phytohormones-which are the plants’ hormones. These phytohormones play a key role in the growth and development of the plant. The plants’ hormones are also regulated naturally through environmental cues, receptors, and genome. The five major phytohormone classes include gibberellin, auxin, cytokinin, ethylene, and abscisic acid. PGRs are used to manipulate those hormones. 

The growth process is divided into stages where each of these hormones serves an important purpose.

Phytohormone Growth Stage
Gibberellin Gibberellin impacts the most during the germination, growth to maturity, and flowering stages with less of an impact, but still an impact, on the fruit development stage. 
Auxin & Cytokinin Auxin and Cytokinin impact the most during the growth, maturity, flowering, and fruit development stages. 
Ethylene Ethylene impacts the most during the flowering and fruit development stages and then again after the seed dormancy stage in the abscission stage.
Abscisic Acid Abscisic acid (ABA) impacts the most during seed dormancy and abscission (when ripe fruit drops). 

How Do You Spot PGR Cannabis?

Though PGR cannabis is impossible to spot without proper chemical testing, there are a few tell-tale signs to flag for at your local dispensaries.


Cannabis plants grown with PGRs are super dense and tightly curled. PGR buds will be elongated and feel thicker than healthy, leafy buds, with a spongy consistency. They’re also rock hard, so they’ll feel weighted than healthy nugs.Also, PGR cannabis will have more brown and red hairs than naturally-grown cannabis. Coupled with the yellow-brown trichomes typical of PGR weed, the red and brown hairs will cause the flower to have a duller, orange or brown appearance.

Texture and Smell

Not only are the trichomes a yellow-brown color, but there are also fewer trichomes on PGR cannabis. Because trichomes produce the plant’s terpenes, PGR weed will have a weaker smell compared to natural cannabis. 

These nugs will also feel either spongey and wet or extremely dense and rock hard. 

Taste and Effects 

Because of the lack of trichomes on PGR weed, the plant carries less terpenes and cannabinoids. As such, this type of weed typically has a harsher, chemical-like flavor.

Generally, PGR weed also has a lower CBD and THC content than other cannabis products, as these cannabinoids are also produced in the trichomes of the plant. To make matters worse, the synthetic chemicals used in the PGR process disrupts the production of the plant’s cannabinoids, further diminishing its effects. 

Is PGR Weed Safe to Use?

Health Concerns

Consuming cannabis grown with PGRs poses several health risks due to the harmful chemicals involved. These risks include carcinogenic effects, toxicity to vital organs, respiratory issues, and potential endocrine disruption. In particular, some plant growth regulators have been found to affect reproductive function in humans and animals

Chronic exposure to PGRs can also weaken the immune system and reduce the therapeutic efficacy of cannabis by altering its cannabinoid and terpene profiles.

Consumer Safety

To avoid the risks of PGR cannabis, it’s best to avoid this type of weed altogether. The best way to ensure you’re consuming safe cannabis is to purchase from a licensed dispensary that provides a certificate of analysis with their products. A certificate of analysis can not only show the cannabinoid and terpene profile for the product you’re consuming, it also details how the product was tested before hitting the shelves – including whether or not the flower was texted for toxins and other pollutants.

Why You Should Get Your Medical Marijuana Card

Veriheal has satisfied millions of patients nationwide by giving them access to these benefits

  • Larger purchase limits
  • Peace of mind
  • Enhanced legal protection
  • Access to higher potency strains
  • Save up to 25% on cannabis purchases
  • Skip the line at the dispensary

PGR Weed vs Natural

Comparison with Natural Cannabis

While PGR-treated cannabis often offers higher yields and more visually appealing buds, consuming PGR weed can pose significant health risks due to the potential presence of carcinogenic and toxic chemicals. Plus, the plant growth regulation process alters the natural cannabinoid and terpene profiles of the cannabis flower, which can reduce the therapeutic and medical efficacy of the weed, as well as the flavor, aroma, and texture. 

In contrast, naturally grown cannabis is generally free from harmful synthetic chemicals, especially when it is purchased from a trusted source. Though it may produce lower yields and less aesthetically uniform nugs, naturally grown cannabis retains its rich cannabinoid and terpene profile. Not only does this natural profile mean better-tasting weed, but it can also provide stronger therapeutic benefits and richer, more balanced effects overall. 

Advantages of Natural Growing Practices

Naturally grown cannabis is significantly better for the environment compared to PGR-treated cannabis. By avoiding synthetic chemicals, natural cultivation promotes healthier soil, reduces harmful runoff, and supports local water quality.

Plus, organic farming practices can protect local ecosystems and promote sustainable energy use – ultimately reducing the carbon footprint and energy consumption associated with commercial cannabis grows.

Overall, naturally grown cannabis not only minimizes pollution but ultimately ensures a healthier, cleaner, and more balanced ecosystem among plants.


Overall, though PGR weed may produce uniform nugs and higher yields, dangerous synthetic chemicals can pose serious health risks and lead to weaker, less flavorful cannabis. 

To ensure you’re using cannabis safely in a way that is best for you, consult with a medical marijuana doctor. Having your med card can open doors to a number of benefits — from tax breaks to enhanced legal protection — but it is ultimately the key to ensuring you’re making the best decisions for your health and your individual symptoms while ensuring easy access to safe medical cannabis. 

FAQs on PGR weed

What does PGR do to weed?

PGRs or plant growth regulators can increase cannabis yield and lead to bigger nugs. However, it can also weaken the effects, flavor, and aroma of weed. 

What is the difference between PGR weed and real weed?

PGR weed is grown with plant growth regulators, which can make for more uniform bud, but also can weaken the cannabinoid and terpene profile of the natural plant. In contrast, naturally grown cannabis keeps its terpene and cannabinoid profile, leading to a richer, more balanced, and overall safer experience.

Is PGR harmful?

Yes, PGR weed can lead to serious health risks such as liver toxicity, lowered immune system, or even cancer. 

Is PGR weed illegal?

While PGRs are banned for use on food crops in many areas,  some cultivators still use them for cannabis growth, as there are no laws explicitly restricting them in the cannabis industry.

What does PGR cannabis do to the body?

Consuming PGR weed poses several health risks due to the harmful chemicals involved. These risks include carcinogenic effects, toxicity to vital organs, respiratory issues, and potential endocrine disruption.


1. National Toxicology Program. NTP Technical Report on the Toxicity Study of
Chitosan (CASRN 9012-76-4) Administered in Feed to Sprague Dawley
[Crl:CD(SD)] Rats: Toxicity Report 93 [Internet]. Research Triangle Park (NC):
National Toxicology Program; 2017 Dec. Introduction.


3. Xu, C. S., Jiang, Z., Shen, W., & Zou, S. H. (2018). Zhonghua nan ke xue =
National journal of andrology, 24(4), 370–375.

4. Pang, Q., Chen, X., Lv, J., Li, T., Fang, J., & Jia, H. (2020). Triacontanol
Promotes the Fruit Development and Retards Fruit Senescence in Strawberry: A
Transcriptome Analysis. Plants (Basel, Switzerland), 9(4), 488

5. Ali, O., Ramsubhag, A., & Jayaraman, J. (2021). Biostimulant Properties of
Seaweed Extracts in Plants: Implications towards Sustainable Crop Production.
Plants (Basel, Switzerland), 10(3), 531.

6. Gupta, R., & Chakrabarty, S. K. (2013). Gibberellic acid in plant: still a mystery
unresolved. Plant signaling & behavior, 8(9), e25504.

7. Khadr, A., Wang, G. L., Wang, Y. H., Zhang, R. R., Wang, X. R., Xu, Z. S., Tian,
Y. S., & Xiong, A. S. (2020). Effects of auxin (indole-3-butyric acid) on growth
characteristics, lignification, and expression profiles of genes involved in lignin
biosynthesis in carrot taproot. PeerJ, 8, e10492.

8. Corbineau, F., Xia, Q., Bailly, C., & El-Maarouf-Bouteau, H. (2014). Ethylene, a
key factor in the regulation of seed dormancy. Frontiers in plant science, 5, 539.

9. Gupta, K., Wani, S. H., Razzaq, A., Skalicky, M., Samantara, K., Gupta, S.,
Pandita, D., Goel, S., Grewal, S., Hejnak, V., Shiv, A., El-Sabrout, A. M.,
Elansary, H. O., Alaklabi, A., & Brestic, M. (2022). Abscisic Acid: Role in Fruit
Development and Ripening. Frontiers in plant science, 13, 817500.

Post Your Comments

Mike Gintoli says:

October 3, 2022 at 7:02 pm

Great article! I suspect that the medical suppliers in Connecticut are using some version of PGR.
Can organic pgr be detected by testing?


Get your medical marijuana card today
Sign up in under 5 minutes