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  • Writer's pictureQueenoftheNorthGenetics

Septoria Cannabis Blight

Septoria Cannabis is a fungal pathogen specific to Cannabis; unlike Septoria leaf spot that affects potatoes and tomatoes.  Septoria Cannabis is becoming far more prevalent in outdoor gardens especially in the Northeast.  

Part of the reason that Septoria Cannabis can become so destructive is because the environment that modern cannabis strains are bred is most often indoors or on the West Coast.  Indoor environments are tightly controlled and rain doesn’t exist.  When growing cannabis outdoors in Western climates there is often a lack of the cool, humid conditions we find in the Northeast. Nearly all modern breeding is not done with cool humid conditions in mind. While the quality of cannabis being created by Modern breeders is incredibly high, none of that breeding takes into account the types of climate and disease prevalent in the Northeast and Mid Atlantic.  

The spores of Septoria Cannabis easily overwinter on infected plant material and in the soil. Over the last two years Septoria Cannabis has entered our gardens.  At Queen of the North Genetics we employ multiple measures.   Several of these measures have demonstrated varying amounts of success due to the weather of the season which also plays a big part in how rampant the spread of the disease can become.  Cool wet, windy seasons will propagate the pathogen far more than warm dry seasons will.  

These measures include:

  1. Keep the area clear of infected debris from the previous season.

  2. Tilling soil to bury active pathogens

  3. Using a biofumigant such as mustard greens tilled into soil

  4. Mulching heavily to bury pathogens

  5. Keeping plants thinned and spread to ensure good airflow

  6. Spraying plants with a number of preventative sprays including Bordeaux mix, sulfur, and a number of other preventative sprays available.

  7. Planting strains that have been chosen or bred for Septoria resistance.

Over the last two years we have found that the best measures to control the spread of Septoria Cannabis is to rotate crops and plant genetically resistant strains. While it is important to do everything that you can to minimize Septoria Cannabis in your garden,  Crop Rotation can be difficult and not always a viable solution with the infrastructure often associated with cannabis. 

This is where our work at Queen of the North Genetics comes into play.  Many Eastern outdoor growers have been fine the first 4 or 5 years because the cannabis blight was not present in their grow space. But once it arrives it is here to stay and only good breeding is a long term viable option. 

What we do here at Queen of the North genetics is vital to outdoor cannabis production in the Northeast.  We have yet to find any other growers/breeders selecting strains that hold up to our climate.   Each year we plant out hundreds of phenotypes and strains, and only save the plants that not only are disease resistant in our conditions but also provide high quality, tight, buds that show unique terpene profiles.  

Thanks for choosing our genetics we are sure you will see the difference.


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