Iron deficiency?

They seem to be growing fine, but this extreme yellow on new growth has me wondering. It's been this way a couple weeks and they eventually grow out of the yellow. Took pics right after seaweed foliar.

Night temps are 50 F so it could be from the cold?

Did you recently transplant or dose them with nutes? Pot plants that are growing rapidly often have new growth that is lime green until they get light exposure for a day or two and start to photosynthesize and go a normal green.

Not sure about outdoor grows but i know my indoor grow had some ISSUES that looked like every deficiency in the book, but it was too cold. At 68. I feel your plant looks allot more normal, as its just very new growth thats yellow, pretty normal.

The yellow growth stays for a week or two which is why I'm thinking it's something other than the normal "new growth is yellow".

They've been in these 10 gallon pots for about a month now so it can't be a transplant issue. Only giving water.

It might really just be cold night temps. I've never grown where it gets this cold at night so my natural instinct is to think its a deficiency. Tomatoes and other veggies never have this yellow of new growth with the same base soil mix.

sirtalis said:

The yellow growth stays for a week or two which is why I'm thinking it's something other than the normal "new growth is yellow".

They've been in these 10 gallon pots for about a month now so it can't be a transplant issue.

It might really just be cold night temps. I've never grown where it gets this cold at night so my natural instinct is to think its a deficiency.

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Yeah thats a bit long to be sticking around. What are your temps like during the day? I know giant swings are not good for the plant and can stress them and stunt them, but also this is all my knowledge on indoor grows, never brought them outside. If they are stressing because of swings that would cause them to slowly get out of that yellow leaf stage in my head

Yea it makes sense. The swings aren't too big...50 at night to 63 during day (with sun). I'd say its chronically low temps, unfortunately can't do anything about it.

My guess is these new leaves aren't getting Iron or Zinc. I have this for my lemon trees that probably can't hurt in 1/4 dose: https://www.amazon.com/gp/product/B00A51Y8ZM/

sirtalis said:

The yellow growth stays for a week or two which is why I'm thinking it's something other than the normal "new growth is yellow".

They've been in these 10 gallon pots for about a month now so it can't be a transplant issue. Only giving water.

It might really just be cold night temps. I've never grown where it gets this cold at night so my natural instinct is to think its a deficiency. Tomatoes and other veggies never have this yellow of new growth with the same base soil mix.

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They should green up in a couple of days with good light but new stuff is always coming up so the center will always be yellowish as long as the plant is growing rapidly. Do you measure their heights once in a while to gauge their growth rates?

I take zinc for my prostate and iron as I'm always on the low end and feed some of that to the plants on occasion. You can buy iron supplement for plants but I never see zonc so I just pulverize a few 50mg tablets of zinc citrate, (get the citrate as it absorbs better in plants and animals like us), and add it to my water. Have to shake often as it settles but once in in there you should see improvement if that's the problem. As those are immobile nutrients if it isn't in the soil the plant can't steal it from older growth. Zn and Fe deficiencies are very similar so if you have one now, use it and if the problem goes away that's it.

Go easy on the zinc as too much will block iron and cause that to be deficient. The plants don't need much. They need more iron than zn.

Too much Ca can block Fe, Zn, K and Mn while low S an MN both cause yellowing of new growth too. Pick a card, any card.

sirtalis said:

My guess is these new leaves aren't getting Iron or Zinc. I have this for my lemon trees that probably can't hurt in 1/4 dose: https://www.amazon.com/gp/product/B00A51Y8ZM/

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That looks like great stuff. Covers everything I mentioned in my last post. Not a lot of citrus up here in the great white north so would have to order it. Only for foliar spraying tho. Good for a quick fix I bet.

OldMedUser said:

Too much Ca can block Fe, Zn, K and Mn while low S an MN both cause yellowing of new growth too. Pick a card, any card.

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Ah I think this is part of my problem. I have pretty hard city water and also use gypsum in my soil mix. I think they have too much Ca locking out some sort of combo of Fe, Zn, etc. Think I'm going to have to avoid gypsum or figure out some water filtration.

I recently bought the BAS Big 6: Boron, Cobalt, Copper, Molybdenum and Zinc. There's no Iron in this, so I'll need to find some source to add to my initial soil mix.

Thanks for the tips, sometimes gets crazy how too much of one element locks out so many others. And all you're left with is some yellow new growth and guessing what the problem is

sirtalis said:

Ah I think this is part of my problem. I have pretty hard city water and also use gypsum in my soil mix. I think they have too much Ca locking out some sort of combo of Fe, Zn, etc. Think I'm going to have to avoid gypsum or figure out some water filtration.

I recently bought the BAS Big 6: Boron, Cobalt, Copper, Molybdenum and Zinc. There's no Iron in this, so I'll need to find some source to add to my initial soil mix.

Thanks for the tips, sometimes gets crazy how too much of one element locks out so many others. And all you're left with is some yellow new growth and guessing what the problem is

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You pretty much have to be a detective to figure out what's going on sometimes. Put all the clues together and pick the most likely suspect.

The first thing I think of when there are problems with micro-nutrients is pH. A little too high and it makes it harder for the plant to assimilate them. Same with too low but has to be really low in comparison.

Just give them what they need but not too much usually works for me.