We’ve been hearing a lot more about PGR’s again in recent weeks and months but what are they, and what do they have to do with Cannabis cultivation?
This week we’ll be exploring the relationship between PGR’s and Cannabis cultivation.
In this piece, we’re not going to give you a science lecture. Instead, we’ll try to avoid the jargon and technicalities, focusing on why growers may use these chemicals and how they can affect the human body when consumed.
What Are PGR’s?
Plant growth regulators are defined by the FIFRA- The Federal Insecticide, Fungicide, and Rodenticide Act (which governs their usage in America) defines PGR’s as “Any substance or mixture of substances intended, through physiological action, for accelerating or retarding the rate of growth or rate of maturation, or for otherwise altering the behaviour of plants or the produce thereof”
PGR’s- Plant growth regulators also sometimes referred to as Plant Growth retardants are a group of chemicals used in agricultural farming on crops such as grape and tomato vines, peppers and aubergines to increase their yield, decrease the frequency of fruit drop and for manipulating fruit development and storage quality.
Although PGR’s have been used in traditional agricultural cultivation of edible crops for decades following their discovery in the late 1920’s with seemingly little harm attributed to their use, it still remains unknown as to the long-term health effects of these chemicals especially when combusted and consumed orally.
It is suspected that when cannabis grown with PGR’s is combusted, the trace amounts of these chemicals become volatile; through heat they break down and become a gas which is inhaled along with the cannabis smoke, potentially becoming toxic and harmful to consumers.
(This is why you see farmers dressed in hazmat suits when spraying these chemicals onto crops.)
Its the potential for inhalation and dermal contact that are of concern here given the concentrated nature of the compound prior to it being sprayed.
These chemicals, when ingested in trace amounts, however, such as in foods produced from sprayed crops, breakdown in the gut and appear to have little detrimental effect on the consumer.
PGRs and The Environment
There is growing evidence that suggests that as well as posing a potential threat to human health PGRs have been found to be environmental pollutants. Residual PGRs in the soil and water are shown to have toxic effects on the digestive organs of fish and their embryos. I would suggest that far more research needs to be done to end this protracted debate once and for all.
PGR’s in food production aren’t even guaranteed 100% safe, as the research and data is seriously lacking to demonstrate beyond any doubt the efficacy and safety of PGRs in food production.
We need more studies that look at the retention of residues in the leaves and fruit of vegetable crops. This should be of interest and concern to regulators and cultivators alike, especially considering that customers are consuming fresh vegetables that have been treated with PGR’s.
So why then are some growers still using PGR’s in the cultivation of Cannabis?
There are three main reasons why:
1. To stop vertical growth and get a head start on flower production during the transition from vegetation to flower stage in cultivation during the first two weeks of flowering.
2. To boost the density and yield of flowers during the mid-phase of flowering weeks three-to-five.
3. To harden the flowers during the final stage of flowering, the final 2 weeks of growth.
Effectively there is only one main driving force behind there adoption of these untested methods and that is profit.
It is interesting to note that the global PGR market is to surge from $3.5 Billion observed in 2014, to $6.4 Billion by 2020 (source) possibly on the back of increased usage in the cultivation of cannabis.
At present, PGR’s seem to be far more ubiquitous in the states than the UK. However, they’re slowly making their way over into the UK market as “Cali” strains and other imports become more popular.
So be aware that the cannabis you’re consuming may have been grown using these untested and unregulated products.
As always, the safest way to access cannabis is to cultivate it yourself. Then you’ll know for sure what has been added to the crop and how the plant has been treated.
As mentioned above, it’s not just PGR’s that are being utilised in the cultivation process, there are also Fungicides, Herbicides and Insecticides all of which are, again being used in domestic food agriculture with little to no detrimental effects to the consumer.
So although these chemicals can be toxic in high doses and require PPE (Personal Protective Equipment) to spray, they seem to be relatively harmless in small doses, such as the amount ingested when eating crops that utilised these or similar chemical compounds in their production. However, in recent years there has been growing evidence showing that PGR’s are carcinogenic, toxic to the liver and may cause infertility.
In Europe and the UK, most PGR’s are either banned or classified and regulated as pesticides. However rather worryingly for us and despite being prohibited in many countries, Paclobutrazol is still licensed for use on apple, cherry, pear and plum trees in the UK.
So keep in mind that your PGR joint and local supermarket apples may both be as potentially harmful to you.
The science is complicated and everyone has their own opinion about PGR’s, the efficacy and the effects of using them in agricultural production, let alone Cannabis cultivation.
That being said, I’d say its far better to air on the side of caution and avoid using these chemicals in cannabis cultivation until there is a great deal more relevant and reliable information available about any potential health risks arising from using PGR’s in cannabis products.
On the other hand, it could be argued that if you’re not overly concerned about your physical health anyway, that consuming cannabis tainted with PGR’s is only as bad as eating take away junk food – however do bear in mind that British takeaway food is linked to obesity, heart attack, Stroke, diabetes and early death. (Source)
Ultimately there is not enough evidence either way on the efficacy of PGR’s in cannabis cultivation.
Until there is sufficient evidence either way, I’d recommend avoiding these compounds and Cannabis cultivated using them.