How to Stop Root Rot If You’re Interested in Cannabis Quality Assurance

Cannabis Quality Assurance
Tending to your plants throughout their growth to get the best out of each harvest. Well-tended plants are more likely to produce larger yields and the higher-quality product in demand from today’s competitive marketplace.

Growers must be vigilant throughout the cannabis plant’s life cycle in order to prevent all kinds of problems that can threaten the health of the crop, including pest invasion and diseases. Root rot is one of those diseases, and can result from pathogen infection.

To understand more about this condition and how to handle it if your plants are affected, let’s take a closer look.  

What Are the Symptoms of Root Rot?

On the outside, root rot can cause your plant’s leaves to appear droopy, curled, and generally unhealthy, just as any soil plant will look following severe over or underwatering. The following can all be symptoms of the condition:

  • Leaves with burnt-looking edges
  • Yellowing or pale leaves with brown spots
  • Old leaves falling and dying off, followed by abnormal and/or slow growth
  • An overall weak or wilted appearance
  • Brown, mushy roots giving off a mildewy or unpleasant odour

If you’re considering a cannabis course, you might be wondering how to confirm that these signs do mean root rot. The easiest way to confirm root rot is to check underneath the plant. Affected roots will look slimy, brown, and twisted, unlike healthy roots, which should be milky white and stringy in appearance.

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Growers need to be vigilant throughout the plant’s growth to spot problems like root rot.

What Causes the Problem? 

All kinds of pathogens can cause root rot. This includes various kinds of algae, bacteria, fungi, and parasites, among other factors. The resulting unhealthy brown roots are referred to as “root rot”. The fungi Pythium is often the culprit, attacking the roots of plants that are already damaged, weak, or nutrient-deficient. The parasite targets seeds and seedlings, threatening a grower’s youngest plants.

A few environmental factors can contribute to the condition, including:

  • Dampness
  • Decaying plant matter
  • Temperature (particularly heat)
  • Lack of oxygen
  • Young roots being moved

Overwatering your plants causes dampness, providing ideal conditions for unwanted fungi growth. The warmer temperatures of the hydroponic reservoir allow spores to thrive, growing especially well between 20–34ºC.

Professionals looking to prevent parasitic invasion should clear the reservoir of any floating organic matter, and be on the lookout for light leaks in the hydroponic system which can lead to dampness. They should also ensure the aeration pump is functioning well, as a lack of oxygen can also produce root rot.

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Unlike the green leaves of this healthy young plant, leaves affected by root rot will wilt and turn brown

How Do Those With Cannabis Industry Careers Address Root Rot?

Those with cannabis quality assurance training will know how difficult it is to get a handle on a problem like root rot once it has set in. Often going undetected for some time with the condition starting at the roots, unwanted microscopic pathogen spores are impossible to spot, and can rapidly multiply and spread through your entire crop. If you do spot a plant with symptoms, remove it immediately so the spores don’t have a chance to spread to nearby plants.

Prevention is your ultimate solution. Root rot develops from spores that can lurk in damp topsoil for a long time, and can also thrive in hydroponic reservoirs. Knowing this, you should do everything you can to prevent the damp and humid conditions most likely to lead to pathogen invasion. Key prevention measures should include:

  • Consistent soil drainage
  • High-quality compost
  • Pest control
  • Root controls
  • Equipment cleanliness
  • Nutrient solutions with beneficial bacteria
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The best solution to root rot is prevention through the right level of plant care and maintenance

Make sure your plants are being fed with the right nutrients, and that you are consistently draining your soil. Ensure your soil is mixed with a foundation of correctly-aged compost, which helps produce good bacteria for combating parasites.

Pest control is also key, as fungus gnats can carry fungi with them. You can keep these pests away by making sure you don’t overwater, and ensuring your topsoil dries completely prior to watering. Finally, be sure to keep all of the equipment of your hydroponic system and the grow-op environment as clean as possible at all times.

Root rot is a dreaded condition for growers that can destroy entire crops, but following these best practices for prevention will give you the best chance of making it to harvest unaffected.

Are you interested in receiving professional training to pursue one of many exciting cannabis industry careers?

Contact the Academy of Applied Pharmaceutical Sciences for more information on its cannabis management diploma program!


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