Purple-stemmed marijuana plants can be a bit scary, especially if you‘ve never seen such a sight before. However, rest assured, it probably just looks a lot worse than it really is and is easily remedied.
If you are an indoor grower, your plant is relatively young with leaves of average size, and the purple stems emanate from the top then that purpling is related to genetics.
Some marijuana strains naturally grow purple stems which cause their budding seedlings to appear even more purplish in cooler temps at night.
Other strains, especially those that show stems of seedlings that have turned purple, and have no other issues, have been genetically modified to do so. You will notice over time that purpling will come and go depending on climate and other factors.
A solution for purple stems
Although you may feel worried when seeing purple stems on your marijuana plants for the first time, it’s important not to rush into any changes for the first 1-2 weeks after discovering them.
This is particularly important if the plant and its leaves both appear to be otherwise healthy. In many cases, waiting for this period will give the plant ample time to return to its lively green color, if it’s capable.
If your plant is experiencing slowed growth, on the other hand, or if its leaves are fading, your plant might have a magnesium deficiency. This nutrient deficiency is one of the most common non-genetic reasons for purple stems.
If this is the culprit, fortunately, it is easily treatable. To ensure your plant has the minerals it needs, simply add magnesium in your next watering by carrying out one of these strategies:
- Use Epsom Salt, by adding one tablespoon per gallon of water.
- Use Cal-Mag per package instructions.
- Use a nutrient system that provides time-released magnesium for your plant.
If you think the purple stems on your plant can be attributed to a magnesium deficiency, make sure to read our other article about how to best identify magnesium deficiency.
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