Purple stems

[Newbie2019]

Why am I getting purple stems? I have read it might be it’s not getting enough calcium and magnesium but I have been feeding cal-mag.

 

[Aqua Man]

It's not cal mag. What's all over your plants? Sometimes it's genetics, stress, temps, nutrient related, or poor plant health.

Can you give some background on the grow. Temps, humidity, bug issues, feeding, lighting etc and some history.... ie. When did this appear, changes made, other plants in the same conditions etc

 

[Newbie2019]

It is diatomaceous earth, I had a gnat problem. That has been resolved. Humidity stays between 37 and 50% temps are between 70 to 77. Lights I am using is y grow led 600 watt equivalent and king led 1000 watt equivalent. I made a lot of mistakes in the first 60 days. Soil was really hot and I added nutes also, burned them obviously. Transplanted into fox farm but left the previous soil also. They have been kicking ass not for the last 4 weeks doing great. I keep using the diatomaceous earth to make sure the gnats stay away.

 

[Aqua Man]

Lights out temps? I can't say for sure but I would lean to overall stress and possibly genetics plays a small part. When you look on the underside of the leaves is the purple stop at the leaf or go into the veins of the leaf?

 

[Newbie2019]

Stops at the leaf. Lights out temps are usually 68 to 70

 

[az2000]

If you're not in flower, I would wash your plants down. That earth on the leaves is blocking light. (Maybe it's not enough to matter. Be careful not to have them in full sun, or under your grow lights while water is on the leaves. The water can act as a magnifying glass and burn.).

You said you give "calmag." How long have you done that? How much do you give? If you don't see other signs of mg def, the stems probably aren't related. But, it's possible you could be overdoing it with "calmag" and causing a problem that can look like deficiency.

 

[Newbie2019]

Thank you for commenting too. I appreciate any input.

 

[Newbie2019]

I used cal mag yesterday and I mixed it about half strength of what it said, the last time I fed it was about 3-4 weeks ago and I also did half strength

 

[916Fisherman]

The purple on some stems look blotchy. Weird.

 

[Aqua Man]

Ok thinking outloud. If your night temps are as you stated it's not to cold. Plant has had some ongoing stress so it could be that. Ph to low causing phosphorus to be locked out.

Now how long has this been like this?

What is your feed schedule, ppm and nutes?

Do you ph your nutrients and run off?

 

[RoyalRoutes]

I’m running chem and my plants have the same characteristics and they’re thriving

 

[Aqua Man]

I’m running chem and my plants have the same characteristics and they’re thriving

Yeah if they are growing well it's not uncommon that it can be genetics. I'm more trying to eliminate it as something else. Get to the root cause kinda thing... It absolutely may be genetics

 

[Newbie2019]

I am still learning. I have not been giving any added nutes since I transplanted in the fox farm. They have still been showing some signs of nitrogen toxicity but has gotten much better. My tap water always test from 6.5 to 7. What is ppm? I don’t do run off. When some water comes out In the drip pan I suck it out with a shop vac.

The purple on some stems look blotchy. Weird.

 

[Aqua Man]

I am still learning. I have not been giving any added nutes since I transplanted in the fox farm. They have still been showing some signs of nitrogen toxicity but has gotten much better. My tap water always test from 6.5 to 7. What is ppm? I don’t do run off. When some water comes out In the drip pan I suck it out with a shop vac.

Ppm is parts per million basically it's an accurate way to measure how much nutrients your are putting in your feed solution.

Next time you water take the run off and measure the ph. If you are below 6 it may be causing a lockout of phosphorus which can also cause purpling of stems. If not and with the other info you have given I would say it's either stress from some of the issues you had or genetics.

 

[Newbie2019]

Thank You. How do you measure ppm?

 

[Aqua Man]

Thank You. How do you measure ppm?

Ppm /EC meter it measure the electrical conductivity of the water and translates it in to ppm. A cheap one works if you decide to get one just shoot me a private message and I can let ya know how to make a reference solution to check it's accuracy ever so often.

Something like this will work.
https://www.amazon.com/TDS-Water-Qu...r&qid=1564787948&s=gateway&sprefix=ppm&sr=8-6