Is this a nitrogen or magnesium deficiency?

caca24

Member
The plot thickens!

I see what appears to be "burned" / necrotic tips to young leaves and I am also spotting some blotching on the leaves. Is this consistent with Mg deficiency still?

I am really puzzled.


IMG_20170613_210811648.jpg IMG_20170613_210910906.jpg
 

Bugeye

Well-Known Member
The plot thickens!

I see what appears to be "burned" / necrotic tips to young leaves and I am also spotting some blotching on the leaves. Is this consistent with Mg deficiency still?

I am really puzzled.


View attachment 3960472 View attachment 3960473
Too much N and not enough Mag. Without mag, no photosynthesis, no chlorophyll production and you get marbled interveinal coloring beginning on oldest leaves first. Treat the mag, it is your issue.
 

caca24

Member
Too much N and not enough Mag. Without mag, no photosynthesis, no chlorophyll production and you get marbled interveinal coloring beginning on oldest leaves first. Treat the mag, it is your issue.
I've already given some epsom salts at last watering. Should I give more?

Could it be pH lockout? I've seen no improvements (and actual degradation since last treatment).

Foliar a bit of epsom....
Do you mean spray it on the leaves? Have any instructions you could point me to?
 

im4satori

Well-Known Member
for foliar spray I would use 1/4 tsp per gallon 2x 3 days apart

but you've already given it plenty

I would hang tight

it takes 3 days min for your plants to respond

what you do today you wont see for at least 3 days

you already dosed 1tsp per gallon to the roots

a normal dose is 1/4 tsp per gallon, I recommended you add 1/2 tsp cuz your def is advanced and I thought it could use a good dose....you ended up added a full tsp which is PLENTY

I understand you only used half the volume of water but that's not how you figure it and you should never think of it in those terms

you have to judge it by the total salinity of the water

had you not double dosed it I would be fine with foliar feeding it lightly but im not sure id suggest it with the large serving it already got

I also would be nervous to spray while having that much leaf curl already

I would just water with 1/4 tsp Epsom salt and maybe 2mls calmag per gallon and nothing more for a bit
 
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caca24

Member
Thanks Satori.

I also would be nervous to spray while having that much leaf curl already
What is the meaning of the leaf curl and how does it relate to foliar spraying?

what fertilizers are you planning to use?
This is my first grow, I am trying to keep it as simple as possible in terms of additives. I used a 28-14-14 fertilizer once during the plant's 5 weeks. I also have another fertilizer where the numbers are all the same that I was thinking I could use during flowering, if necessary.
 

im4satori

Well-Known Member
Thanks Satori.



What is the meaning of the leaf curl and how does it relate to foliar spraying?



This is my first grow, I am trying to keep it as simple as possible in terms of additives. I used a 28-14-14 fertilizer once during the plant's 5 weeks. I also have another fertilizer where the numbers are all the same that I was thinking I could use during flowering, if necessary.
are they time release fertilizers?

leaf curl could mean a few things but they all equal stress

I just wouldn't want spray a plant with salts while have that type of curl hooking down like a hawks claw

commonly that's a potential sign for over fertilizing and spraying the leaf might cause burn if it is in deed a result of over fertilization

whatever is going on its best to correct it thru the root zone ... unless your 100% confident in your diagnosis which is clear cut and obvious

spraying plants with anything ever carries a risk vs reward factor
 

caca24

Member
The picture is 2 days after watering with 1/4 tsp epsom per gallon.

I am seeing an improvement in the young leaves, but the old leaves still look as bad. Will some of them recover (like the ones that are only slightly yellow)?
IMG_20170615_174328502.jpg

are they time release fertilizers?
No, just normal plant fertilizers that you can buy at a botanical store.
 

im4satori

Well-Known Member
Thanks Satori.



What is the meaning of the leaf curl and how does it relate to foliar spraying?



This is my first grow, I am trying to keep it as simple as possible in terms of additives. I used a 28-14-14 fertilizer once during the plant's 5 weeks. I also have another fertilizer where the numbers are all the same that I was thinking I could use during flowering, if necessary.
28-14-14

that's mostly nitrogen with a wee bit of K

anything over 1.75 grams absolute max per gallon would be too much N

with 1.5 grams being about right
but again its mostly nitrogen with barely any k

I assumed it is dry powder, if its liquid it would be 1.5mls per gallon (not grams)
 

jensenbeach1

Well-Known Member
I would stop feeding as often I am starting to see nute burn on your tips. Its always good to have less than more. I can see nitrogen claw also as mentioned previously so nitrogen is fine. All I see is a magnesium deficiency which could easily be the case. I wouldnt start throwing everything at it when all you see is the one deficiency. Also id let the soil dryout more definitely overwatering, its hard for me to withhold myself for watering. I wanted to water my plants 3 days ago and they still dont need any water. 6 days now..., ive been bringing them outside also. Ill contribute some of it to being really wet when i transplanted but my plants have no signs of overwatering at all. As long as you give them a chance to breath and you dont dump water all over the pot you should be fine. I water very slowly to make sure im not over doing it. If i recently transplanted I dont go for runoff and I will water the outside of the pot, it lets the water go into the center if it needs to and the roots vice versa. Sometimes i add the tiniest bit of water just to keep my top soil moist and let the middle and bottom catch up. Just have to feel the surface and lift the pot, the weight of it will be your best judgement.
 

jensenbeach1

Well-Known Member
Overwatering will present itself as a bunch of deficiencies, its best to underwater than overwater. If you can I would let the plant go for a very very slight droop from needing water, weigh the pot. That will be your bottom line, try to stay above that. Obviously it will get heavier the bigger it gets but I promise if you put enough care and attention into watering which you should you will have an understanding for its needs and when it wants it. Theres alot of good people on this site you are in good hands. Your plants looking good otherwise once you get this squared away you will be right back on track. Good luck man, dont get discouraged. :cool:
 

caca24

Member
It seems like the younger leaves are also turning yellow now. Especially the intervenal area. Am I experiencing a different kind of deficiency now?


IMG_20170618_085610432.jpg IMG_20170618_085602592.jpg





Overwatering will present itself as a bunch of deficiencies, its best to underwater than overwater. If you can I would let the plant go for a very very slight droop from needing water, weigh the pot. That will be your bottom line, try to stay above that. Obviously it will get heavier the bigger it gets but I promise if you put enough care and attention into watering which you should you will have an understanding for its needs and when it wants it. Theres alot of good people on this site you are in good hands. Your plants looking good otherwise once you get this squared away you will be right back on track. Good luck man, dont get discouraged.
Thanks! I think it's time to water based on this latest picture. Agree?
 

caca24

Member
The more I am reading, the more I think I may have been chronically UNDERwatering. Apparently, chronic underwatering can create the "claw", burn tips and yellow top leaves as well as other signs of deficiency. The plant is pretty big relative to the amount of soil in the pot.
 

Swims_GD

Well-Known Member
what soil have you used and what nutrients are you using. if they've turned like that without nutes then previous posts are correct with nitrogen an cal mag statements,
when you fed nitrogen what was the p/k ratio, did you double up thinking it would fix the nitrogen because too much p/k in young plants will lock out other valuable nutrients

edit: standard vegetable an plant fertilizers sometimes lie about there contents. as there for outdoor use and usually stronger than indoor nutes, if its miracle grow throw it and buy something tailored for cannabis.

also if you've used standard compost/soil they are usually loaded with nutrients to start with... a lot of nitrogen as its composted plant material after all.
 
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im4satori

Well-Known Member
Thanks Satori.



What is the meaning of the leaf curl and how does it relate to foliar spraying?



This is my first grow, I am trying to keep it as simple as possible in terms of additives. I used a 28-14-14 fertilizer once during the plant's 5 weeks. I also have another fertilizer where the numbers are all the same that I was thinking I could use during flowering, if necessary.
its tru too much K caan lockout Mg but

im not sure how he could have too much p/k if hes only used this fertilizer 1x

its packed with N and has very little p/k

can you tell use how much of this 28-14-14 fertilizer you used
if you used too much high N fert (during bloom) that would cause the green leafs and the leaf curl and cupping

high N during bloom can create other issues with flowering

not enough magnesium can cause the leaf twisting and yellowing... the leaves that are yellowed wont repair themselves toull need to rely on new growth to determine its health

and can you confirm if its water soluble or time released?

if your plants where being under watered the fan leaves would be laying down

if the plants weren't getting enough volume of water and building salt that could be an issue but you've only fert 1x and you've flushed with water and Epsom salt since

id continue watering 1/4 tsp Epsom only every other for a few more days

then get you a proper fertilizer... tell us what it is before you buy it so we can help you choose something that's balanced to some degree

shit youd be better off with a soluble 10-10-10 than using the high N stuff you got

look for something like 4-8-7 or something close to that for bloom
or 7-4-10 for veg

general hydroponic
maxigrow (10-5-14) and maxibloom (5-15-14)would work well
(2 grams of each for bloom or 4 grams of grow for veg)
or floranova and floragrow (8mls per gallon full strength)
 
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caca24

Member
can you tell use how much of this 28-14-14 fertilizer you used

if you used too much high N fert (during bloom) that would cause the green leafs and the leaf curl and cupping

I used 1/4 of the recommended dosage for plants. The fertilizer is plantprod 28-14-14. If you search it on google the first link is the chemical analysis.


It's soluble and the recommended usage is 12.5 ml per 5 liters (+/- gallon).
 
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