Is this magnesium deficiency or something else?

[Charsiguy420]

Hello everyone I am having issues with all my plants and they are showing up with this symptom which I am not sure if its calcium or magnesium deficiency. I use FloraNova Bloom at 600ppm but recently upped it to 900ppm with no improvement. Ph is stable at 6.2 in soil. I looked at many pictures but I still want to make sure I get a second opinion. The water moisture on leaves was from foliar feeding of calcium nitrate(15.5-0-0, 19% Ca) at 200ppm. This is the first supplemental feeding of calcium. Thanks and I appreciate all the help.

 

[Logan Burke]

Hmmmmmmmm...I too use Floranova Bloom, and I have had issues with calcium and Mg in the past, but I am in hydroponics in which that is common, whereas in soil a true deficit of those nutrients is far less common. Right off of the bat, I would say that a PH of 6.2 in soil is on the low side. Soil veterans please correct me if I'm wrong here, but in true soil the PH should be in the 6.5 to 7.0 range. Did this problem only start once you increased your nute dosage, or was it already a problem and you increased nutes in response? We'll get it figured out! I meant to ask, are there any symptoms at all on the newest growth? If your newer growth has been relatively unaffected, I would say that your issue is more on the Mg side of things, although Ca and Mg are dependant on one another and one being out of whack will commonly put the other out of balance as well.

 

[myke]

The tips curling up is the clue,cant remember was reading something not that long ago.Mg could be it,so much to learn.Someone will get it.Good luck.

 

[TheSadVeryBadMadGrower]

I believe she is lacking nitrogen to be honest and quite a bit too.

 

[Charsiguy420]

Logan I personally have read about 6-6.5 being the safe range but you're right it is on the low side. It was around 5.9 before and thats when the symptoms started but then I flushed it and got it back to 6.2 now past couple of days. Nutes have always been around 400-600ppm range (0.8-1.2 EC). After flush i increased the nutes too current levels but it hasn't helped at all. New growth is fine for now, its mostly the older leaves in the middle of the plant, although i can see its slowly spreading to the newer leaves too.

 

[Charsiguy420]

I believe she is lacking nitrogen to be honest and quite a bit too.

Does nitrogen deficiency also cause necrosis? I thought nitro deficiency only made the leaf lighter in color overall.

 

[TheSadVeryBadMadGrower]

Nitrogen Deficiencies
Plants will exhibit lack of vigor, slow growth and will be weak and stunted. Quality and yield will be significantly reduced. Older leaves become yellow (chlorotic) from lack of chlorophyll. Deficient plants will exhibit uniform light green to yellow on older leaves, these leaves may die and drop. Leaf margins will not curled up noticeably. Chlorosis will eventually spread throughout the plant. Stems, petioles and lower leaf surfaces may turn purple.

 

[TheSadVeryBadMadGrower]

If it was a few leaves near the bottom, I'd say not to worry. But since it's spreading it's showing signs of being hungry. For soil, you want your ph up in the 6.5 range.

 

[Charsiguy420]

Growth from the top and close looks like this

 

[Charsiguy420]

Thanks MadGrower, can you look at the pictures above and confirm it is indeed nitrogen deficiency only? Sorry I am just afraid to make more mistakes at this point as this is a clone and would my second grow to be a success. First one ended up with very little flowers and I ended up smoking mostly stunted plant but being something I grew myself I was more than happy to smoke it.

 

[Charsiguy420]

Also I'm curious if sativas are more nitrogen hungry. My other clone that looks like indica dominant gets nitrogen toxicity very easily.

 

[TheSadVeryBadMadGrower]

How to fix Cannabis Nitrogen Deficiency (N) Pics & Symptoms

A nitrogen deficiency causes the lower/older leaves of a cannabis plant to start yellowing, wilting, and dropping off on their own. Learn how to fix it.

www.growweedeasy.com

I apologize if this violates any rules of the forum by posting a link.

Check the link out and give it a read. I'd bet she needs a really good feed. All strains are also different when it comes to nutrients.

 

[TheSadVeryBadMadGrower]

Plants in veg tend to use more nitrogen. Flowering plants use less nitrogen but more P-K.

 

[curious2garden]

Hello everyone I am having issues with all my plants and they are showing up with this symptom which I am not sure if its calcium or magnesium deficiency. I use FloraNova Bloom at 600ppm but recently upped it to 900ppm with no improvement. Ph is stable at 6.2 in soil. I looked at many pictures but I still want to make sure I get a second opinion. The water moisture on leaves was from foliar feeding of calcium nitrate(15.5-0-0, 19% Ca) at 200ppm. This is the first supplemental feeding of calcium. Thanks and I appreciate all the help.

View attachment 4451101

Looks like a K def to me but I'd need to see the entire plant and I don't grow in soil. Let's get you a couple experts who know @Tangerine_ @Dr. Who @Thundercat @Renfro

One of them should be able to help you.

 

[Renfro]

If I remember correctly too much Calcium can lockout potassium. Also pH. Raise the pH to 6.5 - 6.8. I don't like my PPM below 1000.

 

[Tangerine_]

Hey Charsiguy.
It does look there's some kind of lockout happening. And the yellowing appears to be scattered so not nitrogen deficient.
As Renfro said, too much Cal locks out K, followed by Mg and Fe.
But then too much P can lockout calcium along with Cu, Fe, Mg and Zn.
And too much K lockouts cal, Mg, Zn, and Fe.

An abundance of one element can throw off the whole cation exchange. And this can happen in hydro or organics.

Can you provide a little more info?
Water source (starting ppms)
Light, temp, and RH.
And what kind of soil are you in?
And a whole plant pic if you can.

If you do have lockout/salt build up you may need to leech the salts. (I refuse to use the word "flush" cuz the RIU sharks will come for me) lol.

 

[polishpollack]

You need to provide more info. What potting soil? How often do you feed? How often do you water? If you're using soil, 900 is way too high for a soil grow. Even 600 is probably way too high, especially depending on the type of soil. Those are hydroponic ppm levels. Interesting no one else caught that part. What are the day/night room temps? Why are you using a bloom fert when it kind of looks like you should be using a grow fert, until you switch to 12/12 lighting? What effect did the foliar feeding have?

 

[Dr. Who]

If I remember correctly too much Calcium can lockout potassium. Also pH. Raise the pH to 6.5 - 6.8. I don't like my PPM below 1000.

I agree - pH related and deepening from locks due to improper uptake ratio's from the pH issue.

Your pH in soil is too low. 6.5 min and in bloom, shoot for 6.7 or 6.8 This helps P uptake at the proper times.

The whole thing is the plant over time (in a low pH situation) begins to show those related issues...

However. If the yellowing started at the bottom and slowly worked it's way up..... High P is in play here.

Your running a sativa. They can be kinda fussy with pH and available nutrients...

 

[Charsiguy420]

Thanks for the response guys! I didn't think I would get this much help from everyone!
and my bad should've provided more info.
I am currently using
-tap water which comes at 100-110ppm.
-50w led light 6500k
-temp stays around 22-25 Celsius
-RH 40%
-For soil I have been using compost peat soil found at local plant store. ( dont know the npk since I dont have the label anymore but it was recommended for all uses)
-Did a flush on 4th using florakleen 1.3mL/1L until drain ppm was down to 200 and ph 6.5.

You need to provide more info. What potting soil? How often do you feed? How often do you water? If you're using soil, 900 is way too high for a soil grow. Even 600 is probably way too high, especially depending on the type of soil. Those are hydroponic ppm levels. Interesting no one else caught that part. What are the day/night room temps? Why are you using a bloom fert when it kind of looks like you should be using a grow fert, until you switch to 12/12 lighting? What effect did the foliar feeding have?

That part about soil ppm I didnt know. does it still apply if the soil has been flushed? I feed it nutrient water every 3-4th day or when I feel like the cup has gotten significantly lighter, although in the past I used to let it get bone dry before water. Should I be feeding nutrient water with every feed if the gap between feed is a couple of days or follow a schedule of nutrient/plain water? I see mixed answers on forums so I am not sure myself to be honest. I should also mention these are clones of the same plant taken in 1-3 week of flower I cant remember exactly, but have been in veg for about a month now. I am following lucas formula cause nutes are almost impossible to find and when you do find them here they are redicilously expensive. I paid 95$ for 1 quart of FNB. Dont even get me started on AN nutrients. THey only have sensi series in stock and each A+B(1litre) cost 115$. Thats over 200 bucks for entire grow and bloom series. And we dont even have cal-mag here but I am planning to make my own mix once I can get my hands on some magnesium nitrate. Currently they only have magnesium phosphate.
Again thanks for helping in my case and sorry for the long reply. I have also attached pictures.

 

[Logan Burke]

Logan I personally have read about 6-6.5 being the safe range but you're right it is on the low side. It was around 5.9 before and thats when the symptoms started but then I flushed it and got it back to 6.2 now past couple of days. Nutes have always been around 400-600ppm range (0.8-1.2 EC). After flush i increased the nutes too current levels but it hasn't helped at all. New growth is fine for now, its mostly the older leaves in the middle of the plant, although i can see its slowly spreading to the newer leaves too.

If the PH truely was the culprit in this situation, and you've corrected it back, then the symptoms should stop progressing altogether within 2-5 days. Previously damaged leaf tissue will not recover, except for perhaps the very minorly yellowed leaves. Point is, look to see if new damage is occuring to the leaves to determine if you've corrected the situation. As Dr. Who and Renfro said, this is certainly shaping up to be a lockout type situation. The good news is, no matter what the problem, once identified it is usually easy to implement a solution.