Fan leaf stems turning purple

I have noticed that the stems of the fan leafs are turning a purplish color on the top side and moving down the stem itself ,more or less with striped purpling. They are into the 3rd week of flowering. I have them set in organic Promix and have been watering with light doses of Pure Blend Pro Bloom 1-4-5
What I have for lighting are 4 Noma full spectrum led grow bulbs. The plants themselves look great. I do not know the strain as they were grown from random seeds. Should this be a cause for worry? Thanks

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What concentration of pro bloom are you using? Their website says you should be using 30ml/gallon at this stage. Pictures will help. Some times it is the strain and some times a deficiency.

Sound like it could be a magnesium deficiency. Do your nutrients contain magnesium?, maybe post some pictures. Could also be genetics, some of my plants have purple on the fan leaf stems

Normal to see this under led lighting. If all else seems good I wouldn’t worry about it.

I finally got a chance to take a few pics. They are not the best quality but you should be able to see what the problem is . I think it’s more like a reddish purple. As you can see apart from that the plants look pretty good.


Bro that’s a healthy ass plant u got there. Lil’ trimming wouldn’t hurt it though. Keep doing whatchu doing. :+1:

Those look amazing! Purple showing up in the plants, for me, is desired. The beauty of a healthy cannabis plant and varieties they have are breathtaking.

Half my Wedding Cake were purple and half were green. The purple ones have cured out to have slight cheese and very strong chocolate with undertones of diesel. The green smells heavenly, like honeysuckle.

Now you might think that the seeds I bought accidentally were mixed and two different strains. However, the three purple ones were in Soft Pots and not directly under the light in the tent and the three green ones were in AutoPot hydroponic and directly under light, I am pretty sure I wouldn’t have managed to separated two strains that well not knowing which was which. I do store the buds separate.


Most of my plants do that same thing at that age. I haven’t found a cure and they end up fine in the end.

Love the colors. I hope my wedding cake that!

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I wish I could tell you why they turned purple. Only difference was position in the tent and the container/grow method.

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It’s just normal coloring in planta. My ak47s have them. No big deal. Doesn’t affect anything.

Typically the purple stems is a result of Magnesium deficiency. But It could also just be the strain. I would just add some Cal-Mag to your water and it probably will help. But those plants look really healthy so… whatever you are doing, KEEP doing it!


Yea, from what I’ve seen the ak47s have it. Like everyone I’ve seen on here has. Mine look great and have them.

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