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by Lee G . Lyzit
Q
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The leaves on the lower part of my plants are turning yellow . Is this normal given they are in day 27 of flowering ? Thanks !
— Chad S .
Thank you for your question . During the final two weeks of the flowering cycle ( days 42-56 for an eightweek flowering cycle ), it is natural for the lower section of a cannabis plant to turn yellow or discolored . In fact , this is a good indicator the plant has been provided with the appropriate ratio of nutrients for blooming and the plant is putting its energy toward flower production during the final weeks . Having said that , yellow leaves on the lower section of a cannabis plant , either during the vegetative stage or in the early weeks of the flowering stage , can be the result of a few different issues . The most common causes for yellowing leaves on the lower section of a cannabis plant are nutrient deficiency , over- or underwatering , and / or temperature . Generally , the discoloration or yellowing of the lower section of a cannabis plant is caused by a macro-nutrient deficiency . Most commonly , the yellowing of leaves on the lower fan leaves is due to a lack of nitrogen . However , this does not always mean the grower is not supplying the garden with adequate nitrogen . In some cases , the deficiency is caused by the pH value of the medium or nutrient solution . If the soil or hydroponic solution ’ s pH value has fluctuated out of the desired range ( 6-7 for soil , 5.5-6.5 for hydroponics ), particular nutrients will become unavailable for absorption , regardless of how much of that nutrient is present . A relatively inexpensive pH meter is a valuable tool a cannabis cultivator can use to ensure the pH value is within the desired range . Over- or underwatering cannabis plants can also lead to discolored or yellow leaves . Overwatering will reduce the amount of available oxygen around the roots , potentially creating the perfect breeding ground for pathogenic anaerobic microorganisms . If the yellowing on the plant ’ s leaves is caused by overwatering , you will likely notice a slight droopiness in the plant ’ s leaves and possibly copper or brown colored spots on the yellowing leaves . Underwatering can also cause a cannabis plant ’ s leaves to yellow . Underwatering is less likely to be the cause because to get to the point where the plant is stressed enough to turn yellow , other tell-tale signs of underwatering would be obvious , such as wilted foliage . Last , but not least , temperature can play a role in the yellowing of leaves on a cannabis plant . If the ambient temperature fluctuates out of the desired range ( 60-80 ° F ), yellowing of leaves may occur . During the lights off period ( night cycle ), the temperature should not drop below 60 ° F . For the lights on period ( day cycle ), the temperature should not exceed 80 ° F ( the exception would be when supplementing CO 2 ) . Temperature fluctuation above or below the desired range , especially when occurring multiple days in a row , can be the culprit of yellowing leaves . During the flowering stage , cannabis plants will and should lose some of their pigmentation . Generally , cannabis growers don ’ t need to worry about yellowing leaves on the lower section of the plant during the later weeks of flowering . However , if the yellowing is happening during the vegetative stage or in the first few weeks of flowering , an examination of the environmental conditions ( temperature ), the pH of the solution and / or medium , and the nutrient concentration will lead the horticulturist to the cause of the discoloration . Once the cause is properly identified , a horticulturist can take action and quickly rectify the problem . I hope this answers your question .
Keep on Growing , Lee G . Lyzit .
LL
Lee G . Lyzit has been involved in the medical cannabis industry for 18 years . His passion for natural healing drives him to learn as much as he can about the miraculous cannabis plant . Lee breeds his own strains of cannabis to create concentrated glycerine and coconut oil extracts . Aside from cannabis education and consumption , Lee enjoys playing music , gardening , hiking , and cross-country skiing .
18 Maximum Yield