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Red/Purple Leaves


New Member
Hi, I'm Pharazir, a new member, and I've got a question. It may seem foolish but it seems worth asking about. After all, these are our babies ...

We've got several plants whose leaves have, in the last couple of weeks, started turning red or even magenta in color. I've read several postings that point to Phosphorous deficiency as the cause but I wanted to check in, just to be sure, as the description doesn't match mine, exactly, and I'd also like to learn how best to correct the situation.

Here's a picture of the plant. The leaves, as you can see, are a deep reddish/magenta. The leaf-stems (petioles?) show no sign of red or purple on them. The leaves, however, are heavily colored:

These plants are from found seeds of unknown origin (culled from stashes before Oregon legalized). They have grown outside, for the most part, in 1-gallon pots, though we've moved them indoors when the weather was too wet (we read that they don't like too much water and that they should be watered thoroughly whenever the soil is dry an inch below the surface). They were subjected to too much watering in August, when we were on a trip (not that kind) and didn't want them to expire from heat or thirst. We've corrected that as noted above.

Even the tiny, new leaves show this red/magenta color. We used commercial potting soil. All the ones planted in the potting soil exhibit this red color. We have one plant that was planted in different soil; its leaves do not show this color. I checked the soil's pH with a digital meter; it's around 5.3

All the plants are budding, though they are only about 39" high.

We read about Phosphorous deficiency about 2 weeks ago and started giving them Miracle-Gro bloom once a week or so. We saw a recommendation for Miracle-Gro Tomato plant food and got some of that, though we haven't tried it yet. There have been no visible results so far; the photo above was taken this afternoon.

We don't want to overdose them with nutrients but we'd like to correct this problem as soon as possible. Does this look like Phosphorous deficiency? If so, how much should we give them and what results should we look for as signs that this problem is solved?

Whatever the answer, thanks so much for taking some time and energy to read and, perhaps, respond to this posting. Any words of wisdom are greatly appreciated and any suggestions will be gratefully received and carefully considered.

May the Stars Shine Upon Your Path!


Nug of the Year: 2016 - Member of the Month: Sept 2015, Nov 2016 - Nug of the Month: Oct 2016 - Plant of the Month: May 2016
When I was starting out and used to overwater during flowering, I would get dark purplish foliage like that. I also took it to mean phosphorus def- with overwatering being the basic problem/cause. In my case, one of the symptoms was that the leaf stalks would get extremely brittle, and snap off instead of bending and tearing as they would normally do. Is there a way for you to check this?
Part of my problem at that time was that I had them in pots that were too big so they weren't getting a chance to dry out well between waterings.
I would doublecheck that you're not currently still overwatering. Try lifting the pots to feel the weight. Compare to a pot of slightly moist or dry soil. They should get to be quite dry, even just before wilting, before watering. When watering allow plenty of runoff.
I think if temps get down into the 50s then you can get some purpling especially with some strains. However- if you are having cold nights and also overwatering- your plants won't be happy about that. Also- as you probably know, some strains tend to purple, from genetics.

Robert Celt

New Member
Hello Pharazir and welcome to :420:

More pictures of the overall plants would be nice, but from what I can see with the girls being in flower and what appears as green leaves in the background, I would say you have a purple strain showing its autumn colors :)


New Member
First, thank you all! You've set our minds at ease and we greatly appreciate it!

Now, the answers: We have almost certainly overwatered (and probably still are) and it has been chilly in the evenings, on clear days.

Weaselcracker, we have using the "if the soil is dry an inch below the surface, it's OK to water" rule of thumb we saw on another website. I never thought to compare the weight of a pot of dry soil to ours; I'll do that tomorrow morning. Based on your observation, though, I'm certain that we've overwatered. Thanks for pointing out a simple, out-of-the-box way to check!

Ricky Bobby, the temperatures here have mostly been in the 65˚-95˚ range during the days (with occasional forays into the 105˚-110˚ area) and generally 50˚-70˚ at night with occasional dips down to 45˚ or so.

TheCelt, I didn't know that there WERE purple strains. My best friend remarked that perhaps it was just a red strain but we hadn't seen anything so deep and purple. I had, as I mentioned, a dozen or so seeds culled from stuff I've gotten during the last few years and these may have all been from the same strain. We planted four of them at the same time and they all look like this ... except one. It is just a 5" high central stalk with nothing but buds on it. I'ts never had more than half-a-dozen leaves at a time; just this big stalk of bud. I'll post a photo.

I can see that, though I literally grew up in the Haight-Ashbury in the mid-60's, this stuff has come a long way and there's a lot I don't know. Thanks for those reassuring words, everyone.

We will absolutely check the comparative weight tomorrow and I'll post some additional photos tomorrow, as well. Any words of wisdom will be greatly appreciated!


New Member
plant looks great to me, some phenos have purple leaves, check out the colors on dark devil strain online that ones crazy! when temps tend to get really cold or drop cooler than a 10 degree difference it can also bring out some purple coloring, the other leaves look healthy and green, she looks great keep it up my friend and youll have a beautiful potent harvest.


New Member

Here are the photos I promised a couple of days ago. I've included one of the ladies in red, one of the green one and one photo of the bud-acious little girl. Please check them out and let me know if there's anything you think we should be concerned about. They are all about 3 feet high (except, of course, the Bud). We took your advice and cut back on water. We're leaving them outside (and sheltering them from rain) so that they can what light the waning of the season has to offer.

Thanks and Best Wishes!

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