Iron Def?

overmyhead

Well-Known Member
I searched several threads on problems with the color changes seen in the pics and it looks like an iron def but wanted to get some second opinions. The pics are a close up of a flower from that plant, a top view, and a flower from the plant next to it - same batch of clones. Also here is the test on what can cause it and how to treat it. One of the causes is possible over irrigation. I gave some of them a little water when they werent completely dry because I wanted to get some BT in the top layer as I have been seeing adult fungus gnats (I've gotten about 50 on stickys over the past month but havent seen any of the larvae in the soil and put bt in every watering. I am pretty sure my ph is fine as I'm using pro mix and have ph'd to 6.3 on every watering. It says to just give it something with Iron in it on the next feeding and my question is: if these plants arent drinking like the others who knows when the next feeding will be and will unsulfered molasses (the bottle doesnt say blackstrap though - it's "wholesome sweeteners organic molasses" will that be the iron supp I need or should I do something foliar? Thanks!

Forgot to past this:

Iron (Fe) deficiency
Pronounced interveinal chlorosis similar to that caused by magnesium deficiency but on the younger leaves.
Leaves exhibit chlorosis (yellowing) of the leaves mainly between the veins, starting with the lower and middle leaves.
Caused by factors that interfere with iron absorption of roots: over irrigation, excessive soluble salts, inadequate drainage, pests, high substrate pH, or nematodes. This is easily corrected by adding an iron supplement with the next watering.
Fe is unavailable to plants when the pH of the water or soil is too high. If deficient, lower the pH to about 6.5 (for rockwool, about 5.7), and check that you're not adding too much P, which can lock up Fe. Use iron that's chelated for maximum availability. Read your fertilizer's ingredients - chelated iron might read something like "iron EDTA". To much Fe without adding enough P can cause a P-deficiency.
Note that when adding iron to the solution, it is often necessary to not use fertilizer for that watering. Iron has a tendency of reacting with many of the components of fertilizer solutions, and will cause nutrient lockup to occur. Read the labels of both the iron supplement and the fertilizer you are using before you attempt to combine the two.
 

overmyhead

Well-Known Member
I think this pic might show it better - some of the yellowing is starting at the tips but the most peculiar thing is how it forms a band across all the fingers on some of them.
 

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Doctor Cannabis

Well-Known Member
This is more probably copper def, looks very much like iron def, but in iron def new growth comes out completly light green or yellow.

Molasses of any kind will fix this. 2tbs/gal every watering.
 

MrFishy

Well-Known Member
How many weeks into flower are you?

I find a N boost at first sign of deficiency in flower, usually week 3 or 4 here, after a flush, stops the yellowing through the rest of the grow. (in addition to flowering nutes)
 

overmyhead

Well-Known Member
Thanks for the feedback, I am so frustrated - nothing you find or hear seems to match. The new growth is very yellow btw. Here is what I found about copper def and I don't think it really matches bc my new growth isn't dark green. But it says too much C can cause a Fe def! ?!? You're damned if you do and damned if you don't. It seems like these top shelf nutrient solutions would have all these trace elements covered! I started addming molasses last feeding at 1tbsp/gal.

But all of my plants are drying at different times so the schedules get really confusing.

Definitely a compelling argument for Hydro - at least everything is the same for each plant.

Heres what I found about copper:

opper
Copper is a constituent of many enzymes and proteins. Assists in carbohydrate metabolism, nitrogen fixation and in the process of oxygen reduction.
Copper Deficiency
Symptoms of deficiency are a reduced or stunted growth with a distortion of the younger leaves and growth tip die-back. Young leaves often become dark green and twisted. They may die back or just exhibit necrotic spots. Growth and yield will be deficient as well.
Copper Toxicity
Copper is required in very small amounts and readily becomes toxic in solution culture if not carefully controlled. Excess values will induce iron deficiency. Root growth will be suppressed followed by symptoms of iron chlorosis, stunting, reduced branching, abnormal darkening and thickening of roots.
 

overmyhead

Well-Known Member
How many weeks into flower are you?

I find a N boost at first sign of deficiency in flower, usually week 3 or 4 here, after a flush, stops the yellowing through the rest of the grow. (in addition to flowering nutes)
Fishy, just read this - I thought a N def was a subtle yellowing of the leaves starting at the bottom? Mine look like they're tie dyed, and its two different straings showing it?????????????

I'm about to say f it and just keep feeding them well and let it ride - but the buds on the badly affected plants havn't really changed in a week so maybe I should trash them and move some clones in???

But then, look at my other thread for the crazy shit that they've been experiencing!!!!!!!!!

https://www.rollitup.org/marijuana-plant-problems/238428-all-new-growth-looks-singed.html
 

Doctor Cannabis

Well-Known Member
Copper Deficiency
Symptoms of deficiency are a reduced or stunted growth with a distortion of the younger leaves and growth tip die-back. Young leaves often become dark green and twisted. They may die back or just exhibit necrotic spots. Growth and yield will be deficient as well.
That is so balony. It's the old leaves that turn dark green, the new growth starts turning yellow from the tips. The people that write this stuff should at least pick up a textbook or a pamphlet or something...

Double the molasses. 2 tablespoons/gal is what you need in order to fix this.
 

overmyhead

Well-Known Member
Doc - thanks, for some reason I trust you but isn't there a lot of calcium in molasses? and can't too much calcium lock out iron??? I think I am going to build a solid soil next time and not have to go through all this!
 

overmyhead

Well-Known Member
Doc, also, what about all the extra potassium in the molasses - cant it cause other nutes to be locked out too??????? I am really confused as to why there isn't just a one stop nutrient out there.
 

Green Cross

Well-Known Member
Doc, also, what about all the extra potassium in the molasses - cant it cause other nutes to be locked out too??????? I am really confused as to why there isn't just a one stop nutrient out there.
You're PH is low. Mine is always between 6.7 and 7 (neutral)

But you definitely have an abnormal deficiency going on, or lockout. I don't remember reading what nutes you're using, but I'll check after I post.

Worm casings have nearly every micro nutrient you need, and it only has a N or 1 on the N-P-K, which is good, because you don't want to give it much nitrogen in flower.

I'd try to raise the PH and top dress with worm casings.

Feel free to PM me :peace:

Correction: Forget about the PH, it's not that bad for hydro (hydro likes a little lower PH), although that could be a little low for a specific strain that likes a higher PH. It's probably something else.

Add add a micro nute to your feeding schedule?
 

Doctor Cannabis

Well-Known Member
Molasses only has trace amounts of microelements or K, but still enough to fix any micro def.

Situation like "X lock out Y" is only admissible if you have too much X. K locks out iron for example, but only if you really, really overdo it.
 

overmyhead

Well-Known Member
greencross - thanks, last time i tested my ph in a couple pots it was just under 7 (those little capsule test kits) but it would take forever to do all of them. I just don't understand how my ph could be too low when I am using pro mix (with dolomitic lime) and always ph my water / nutes to 6.3-6.5. Plus I have hardly used any nutes. Someone else told me that I should drop my water to 6??????????? I like the worm casting Idea and next go round will definitely be pre seasoning my soil mix. This if ridiculous and takes all the enjoyment out of it - i really feel like i have children that are dying. You can look at my sig for the grow, but I will be using pureblend pro from here on.

I do have a digital ph meter for liquid - can i use this to test the soil somehow???
 

Green Cross

Well-Known Member
Yeah I realized you're in hydro after my reply.

I wish I could help you, but I'm in the dark as far as hydro goes.

I know certain strains like a little higher PH than others, but not even sure if that's the problem now. Hydro typically runs more acid than soil

GL
 

overmyhead

Well-Known Member
well still no change but the plants seem to be powering through it. I am starting to think that there were some labels mixed up during a transplant hence the wimpy flowers on some of them. You see, the pure power were like that in early flower last time and I guess I have a couple more than I thought cause the two that have the little flowers look and smell just like the pure powers from last time. Oh well, I really didn't want that many of them but oh well. It makes a great addition to the chocolope for those whose hearts race.

Will post some recent pics in my journal tomorrow.
 
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