Purple under fan leaves and all stems

Freda Felcher

Well-Known Member
I have some skunkberry in veg growing outdoor and planted in the ground. They are all between three and five foot and will begin pre flowering in the next couple weeks. I have two groups of them in separate locations and while one group looks great, the other has some problems. In the past couple weeks i have noticed the one group has slowed new veg growth, all stems have gone purple and hard, and the undersides of the fan leaves are purple on the lower branches. I have read several of the deficiency faq's and they all say it could be Mg or K deficient. I will have some pictures up tomorrow, but really it's how its described. Purple hardened stems, slow growth and purple undersides on lower fan leaves(top of leaf stays green but bottoms are deep purple). If anyone has any ideas, please pass them along, thanks:)
 

veggiegardener

Well-Known Member
Give the plants light feedings of the nutrients mentioned, and time. I've had a few plants do this late in flowering. I assumed it was probably temperature related. I've always associated it with a pleasant flavor.
 

Freda Felcher

Well-Known Member
They are due for water tommorow, i'll add in some call mag. I should have mentioned before that i am feeding them with guano tea, using mexican, peruvian and jamaican guanos with kelp and molasses. The water i use is from the creek, has been tested and is pristine so i really have no doubts about water contaminates.
 

cobyb

Active Member
The purpling of stems is due to a lack of available phosphorus during the start of flowering. The plant draws it's available P from the leaves and stems at the base of the branch. The intensity increases as the distance and demand increase. I think inevitably the plant will purple those stems during flowering as it draws the available necessary nutrients..

These are my observations, and this is my first year growing Cannabis.
 

Freda Felcher

Well-Known Member
Here's a thought I just had. The plot i am having problems with is about thirty yards from a cornfield with prairie grass set aside separating the two. The leaf beetles were thick in the corn this summer so farmers in the area have had to resort to ariel spraying. Do you think drift from insecticides could have caused my plot to stress, slow growth and turn purple? I don't see any difference in any of the native vegetation growing near by so idk?
 

cobyb

Active Member
Here's a thought I just had. The plot i am having problems with is about thirty yards from a cornfield with prairie grass set aside separating the two. The leaf beetles were thick in the corn this summer so farmers in the area have had to resort to ariel spraying. Do you think drift from insecticides could have caused my plot to stress, slow growth and turn purple? I don't see any difference in any of the native vegetation growing near by so idk?
No. The plant genetics are probably purpling the plant due to it switching over and using readily available nutrients at the leaf site.
 

Freda Felcher

Well-Known Member
Cobyb, thanks for the response, maybe you didnt read it, but I have another plot of this same Skunkberry growing in a separate location and it looks great. Same feeding schedule, same nutes and similar sun light throughout the day. i just can't explain how one group looks stellar and the other is slow going, hard stemmed and very little new growth?
 

Freda Felcher

Well-Known Member
No. The plant genetics are probably purpling the plant due to it switching over and using readily available nutrients at the leaf site.
The genetics are Skunkberry and do have some purple tendencies, but that's when it's late in flower. My plants are STILL vegging. Preflower starts in another next week or two. And that still wouldn't explain why one plot of SB looks normal and healthy and the other location looks fooked.
 

Freda Felcher

Well-Known Member
http://growweedeasy.com/phosphorus-deficiency-cannabis

What is the medium? What is your ph? Temperatures at night? Both sites receive the same water?
Soil, as I already stated. It's summer, night temps are not cold enough to be causing it to purple. My soil and water both were tested before planting, no lime was needed to adjust Ph, similar soils in both plots. As I said before, both plots receive the same water and nutrient amounts from the same water source. Thanks for the help but I'm looking for someone who has already dealt with this, peace freda
 

Freda Felcher

Well-Known Member
Give the plants light feedings of the nutrients mentioned, and time. I've had a few plants do this late in flowering. I assumed it was probably temperature related. I've always associated it with a pleasant flavor.
Thanks for the advice Veg, by any chance do you have any experience with pesticides or herbicides? Or possibly have read about the effects agricultural chems like that have on marijuana plants? I'm going to water tomorrow and throw in some cal mag, hoping its just MG def, but still doesn't explain why the other plot isn't?
 

cobyb

Active Member
I have some skunkberry in veg growing outdoor and planted in the ground. They are all between three and five foot and will begin pre flowering in the next couple weeks. I have two groups of them in separate locations and while one group looks great, the other has some problems. In the past couple weeks i have noticed the one group has slowed new veg growth, all stems have gone purple and hard, and the undersides of the fan leaves are purple on the lower branches. I have read several of the deficiency faq's and they all say it could be Mg or K deficient. I will have some pictures up tomorrow, but really it's how its described. Purple hardened stems, slow growth and purple undersides on lower fan leaves(top of leaf stays green but bottoms are deep purple). If anyone has any ideas, please pass them along, thanks:)
Mg or K will not cause purple stems branches and leaves. "Purple hardened stems, slow growth and purple undersides" is caused by Phosphorus not being able to be taken up by the plant. Your separate plots have different soil compositions. Purple under the leaf, is not in a description of Mg or K deficiency.
 

Freda Felcher

Well-Known Member
Mg or K will not cause purple stems branches and leaves. "Purple hardened stems, slow growth and purple undersides" is caused by Phosphorus not being able to be taken up by the plant. Your separate plots have different soil compositions. Purple under the leaf, is not in a description of Mg or K deficiency.
I agree it's a site specific problem. But the soil is the same in both plots, I dug out 3ft deep by 2ft wide, pitched the soil and added my own soil mix. I used muscatine rich top soil with micho, perlite, mushroom and cow compost, worm casting and guano as my mix. Both plots have the similar natural soils surrounding them. I did soil tests on both plots and the Ph was the same and well within range. As I said before, i'm feeding both plots the same water and tea nute amounts. I'm still going to hit them with cal mag because its been a while and a dose is due anyhow. I'm going to do some more research on Phosphorus def. thanks for the link:)
 

cobyb

Active Member
How about before you cal/mag them, you do research on Phosphorus? They are your plants, but you should not be such a miser when it comes to advice.
 

Freda Felcher

Well-Known Member
Read your Bible. Page 358.
Still doesn't explain why one group looks that way and the other doesn't when i'm feeding them all the same amount of nute/water feedings with same soil mix. As I mentioned before, these are all from same clone, skunkberry. My best guess is still going to be herbicide spray from the planes, from what i am reading, it can block certain uptakes of nutrients in plants its not intended for. That may explain why they are nutrient deficient while getting proper nutes. The pesticide drift may have caused my plants to stop taking in Phosphorous.
 

Freda Felcher

Well-Known Member
How about before you cal/mag them, you do research on Phosphorus? They are your plants, but you should not be such a miser when it comes to advice.
Haha, "miser", what, do you want a freakin bozo button or something? Am i supposed to give you props or a pat on the back? Wheres the thumbs up button? You relentlessly force this P def theory down my throat yet have no conclusion as to why its happening.....i already politely asked you to buzz off earlier, thanks for the advice asshat.
 

veggiegardener

Well-Known Member
A mystery. Sometimes there are things that aren't easily explained. You could have a lab analysis done of both soils. I doubt much can be done to reverse things. Maybe a good flush, followed by light feedings of a well balanced fertilizer. Last year I had some weird things happen in one of my greenhouses. Three plants collapsed(died) in a three week period in June. No discernible cause.
 

cobyb

Active Member
@Freda Felcher Deleting your comments and slurs will not make your conscience and karma better.

Your willful introduction of more calcium will probably compound your problem as you deplete more unavailable phosphorus.
 
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