purple stems

[lildog]

stem and petioles are reddish purple and turning a lighter green. Not sure if its the strain or some sort of imbalance.

[DW2]

Howdy lildog, I have noticed the same purple color on the stems of my plants in the past. It is always on the side facing the lights. I believe that it is a normal reaction to the light (a cannabis tan, if You will) as it does not appear on stems that are shaded by the other leaves.
I would not worry about it as I have not had ant problems with my plants that did the same.

[Cannabliss]

Purple stems and petioles may be the beginning signs of a Magnesium deficiency. It's doesn't look as serious, but I'd keep an eye on that. Might want to add a little Mag supplement.

[Shade]

Purple stems can be either just a normal genetic expression or a sign of phosphorus deficiency. I think there would have to be brown spots on leaves before making that call.

What is your growing medium? It looks like coco coir. What are all the nutrients you're using? I looked up those 2 in your pictures and so far I don't see micronutrients aside from calcium. Also, does the feeding schedule say to mix them during veg? There's very low potassium(1/10 nitrogen) and no phosphorus.

Just curious, because otherwise the leaves are looking very good and healthy to me. They are light green, but from what I've seen, color fluctuations without spots are normal.

[Flockshot]

Red stems can be N-P-K-or Mg, or genetics, so you will need something more to know for sure.
If it was N you would already be seeing yellowing in the leaves
If it was P you would see light green spots in the leaves that will become dead spots
If it was K you would see the tips and edges of the leaves start t die
If it was MG you would start to see yellowing between the veins of the leaves.

If you figure it out please let me know because I just went through a entire grow with red stems on a Gorilla Glue and have no idea if it is genetics or not. The plant did fine.

[GreenhouseEffect]

It also could be brought about by the temperature, some strains, when the nighttime temps dip low enough, will change colors in various parts of the plant. Interestingly enough, that color change is because the plant can't take up a nutrient it needs, because of the cooler temperature. In that case though, it's normal, and the plant is fine.

I can't tell for certain, but it does look more like just normal plant genetics to me than a problem.
What strain is it?

[Dannnz33]

I’m growing GG#1 and I’m having the same effect and I just tested my soil and I’m in surplus of everything aside from K on one of 3 plants that I’m at adequate so I do believe it’s plant genetics and possibly like someone mentioned could have something to do with the light cuz it’s on the long top stems not the ones below.

[Rwise]

I have 2 Rusty Glues in the same soil next to each other. One has purple stems to the leaf, the other does not. In my case it's a genetic thing.
Dan welcome to GWE, GG is one strain that I have read is not stable, so no surprise on the purple,,,

[Weed Pharma]

If the purple is only on the side facing a light, it’s a general indicator of a nutrient deficiency- which may or may not need treatment.
Genetics however, causes the entire stem to purple.

[Rwise]

I looked at the under side of the leaf, not purple. But all the clones display the same as does the one without purple.

[Colombo]

This may answer your question. https://www.ilovegrowingmarijuana.co...ems-marijuana/ I would also check your plants for bugs/mites ? your leaves have indicators.Good Growing !!

[FatBoy40]

Purple stems can also be caused by fans blowing too hard on them or wind burn if you will. But only the side toward the light seems to indicate something else.