Why Are Stems and Leaves Of Cannabis Plants Turning Purple?

When a cannabis plant or seedling has a purple stem without any other signs of problems, it is often the result of genetics. However, sometimes you’ll see red stems which can sometimes be caused by stress, environment or pH problems.

Below are some things you need to know about this.Let’s say you are growing your plants indoors, the plants are still fairly young and the leave are average in size, but you notice the stems have turned a purple color starting from the top.

Purple stem

If you notice the stem of your seedling or marijuana plant has turned purple and there are no more indications of issues, this means their problem is genetic. There are certain marijuana strains that automatically grow with purple stems, more so when the seedlings are budding, or even once the plants start receiving cooler temperatures during the night.

Solution for purple stems

If your plant seems to be in good condition aside from the stems being purple, refrain from making any changes for a one or two weeks. The majority of the time the plants will turn green fairly quickly. Provided that your leaves appear to be healthy and there aren’t any of issues you are aware of, most likely the purple stems are nothing to be concerned about.

If you suspect that your marijuana plant may have a nutrient deficiency, maybe because the plant growth has slowed down or the color of the leaves is fading, then your plant could be magnesium deficient. This can sometimes create purples stems.

Plant with all stems purple

If this is the case, the issue will be resolved with ease by adding more magnesium the next time you water your marijuana plant.

Here are some great magnesium sources for your plants:

  •  Epsom salt, just add 1 tablespoon per gallon
  •  Cal-Mag
  •  A nutrient solution that works well with marijuana has the proper amount of magnesium for your plants

Usually, your purple stem problem is nothing to worry about at all. But to be on the safe side check for any signs of magnesium deficiency. Take a look at our article on identifying magnesium deficiency for more detailed information. If there is no nutrient deficiency, then luckily, purple stem will only last for a short time.

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