Cannabis Cross-Pollination: What Are Its Risks?

Cannabis Cross-Pollination
Cannabis Cross-Pollination

Cannabis cross pollination is not an altogether new idea to cannabis farmers. The possibility was well known ever since the time when large scale cannabis cultivation for medical purposes started. When cannabis plants like marijuana or CBD hemp are grown outdoors close to industrial hemp farms, the industrial hemp pollen may pollinate the CBD hemp or marijuana plants, thereby reducing their cannabinoid content significantly.

What Is The Difference Between Industrial Hemp, CBD Hemp And Marijuana?

Industrial hemp is grown for using its fiber in the textile industry and seeds as food supplement. The cannabinoid content of industrial hemp is given no attention, and farming practices intend to increase the yield in terms of seeds and fiber. However, CBD hemp and marijuana is grown to obtain its essential cannabinoids like CBD, THC, CBN and CBG that have several applications in medicine and wellness industry.

Understanding Cross-Pollination In Detail

Cannabis is a dioecious plant, indicating that both male and female flowers are borne on separate plants. However, there are monecious plants also with male and female flowers on the same plant. In some cases, stress can induce the production of male flowers on female plants. But these are exceptional cases. The plant is normally dioecious in nature. The flowering process is initiated in seasons when the lengths of day and night are equal. The flowering period of male cannabis plant ranges from two to four weeks and a single male flower produces about 350,000 pollen grains.

 On finding that preventing pollination by growing female plants alone could increase the crop yield, marijuana farmers started growing female plants only. The same applies for CBD hemp. However, the case of industrial hemp is different. Industrial hemp fields usually contain more male plants due to the higher costs associated with producing female clones.

When industrial hemp and marijuana/CBD hemp farms are close to each other, the pollen from industrial hemp plants pollinates the marijuana/CBD hemp flowers. The cross-pollination has an adverse impact on the yield of marijuana and CBD hemp. A study found that cross pollination decreases the yield of essential oils in cannabis flowers by 56%.

How To Prevent Cannabis Cross Pollination?

Here are some of the steps to decrease cross-pollination.

  • Geographic or physical isolation: Maintaining a minimum distance of 10 miles between outdoor CBD hemp/marijuana farms and industrial hemp farms is a generally recommended solution to prevent cross-pollination.
  • Indoor farming: Growing marijuana and CBD hemp indoors can prevent them from being pollinated by industrial hemp pollen from outdoor fields. However, the indoor growing environment should be equipped with proper air filtration systems.

Predicting the possibilities of cross-pollination and employing measures to prevent them beforehand is critical in ensuring optimum cannabinoid contents in marijuana and CBD hemp.