N deficiency?

[cowtown]

Hey everyone. I read through the sticky Guide to nute deficiency or toxicity in here but I still have a question. Been feeding once a week and I am not sure if this is an N deficiency or not. The guide says the leaves usually yellow at the bottom first but it's the tops that are yellow a bit and one plant is kind of lime green instead of dark green.

I think it's N because the two yellowing ones are twice as large as the two green healthy ones so I think they might not be getting enough. They have all been fed the same and planted in the same soil, the two larger ones were started one month sooner is all.

Also, should I be thinning out or trimming the really bushy plants? Never had two this full of leaves before. Thanks for the advice.

 

[cowtown]

So I tied the plant down for a better picture. Here you can see the yellowing better at the top and the rest is okay.

Any idea?

 

[JayBio420]

View attachment 4384938 So I tied the plant down for a better picture. Here you can see the yellowing better at the top and the rest is okay.

Any idea?

How many plants are there? First look at the yellow leaves and determine if they are the top or bottom of the plant? Are they large older leaves? If so then it is a mobile nutrient. I can see nice green top above it so I think it may be a mobile problem. Looks like a pottasium deficiency, but I notice some cupping of the leaves which indicates some stress. As potassium helps fight stress, I would reccomend getting some pottasium sulphate and top dressing and watering that in.

You could try an inch of compost or worm castings and that would help whether it was pottasium or nitrogen you need.


I am not entirely certain that’s the problem. Perhaps someone with more experience can help.

 

[cowtown]

Thanks. I have four and two of them are yellowing from the top down. The other two are green and healthy. They get the same amount of sun, water, and feeding this is my second grow and never had this problem before and last time I grew 27 of them.

I looked at those charts you added and dont think it's an NPK issue. Been feeding with 24 8 16. I also added the proper amount of Calimag.

Edit. I fed them yesterday and the yellowing got worse this morning. Overfed maybe? Seems odd though since excess N should have the leaves a really dark green no?

More yellow this morning.

 

[Nutty sKunK]

Thanks. I have four and two of them are yellowing from the top down. The other two are green and healthy. They get the same amount of sun, water, and feeding this is my second grow and never had this problem before and last time I grew 27 of them.

I looked at those charts you added and dont think it's an NPK issue. Been feeding with 24 8 16. Maybe a lack of P?

It’s not N. That’s lack of magnesium.

Interveinal chlorosis in the middle of the plant.

Cure with some unscented organic Epsom salts. 1-2tbsp per gal since they are outside.



Edit: Also, the cupping of the newest growth is another indicator of Mag.

 

[cowtown]

I

It’s not N. That’s lack of magnesium.

Interveinal chlorosis in the middle of the plant.

Cure with some unscented organic Epsom salts. 1-2tbsp per gal since they are outside.



Edit: Also, the cupping of the newest growth is another indicator of Mag.

Thank you. I kind of thought that after I knew how much N they were getting. Never had an issue like this before. I added the proper amount of Calimag and watered yesterday.

Looking at the charts posted above it almost looks like iron, sulfer, or zinc may be an issue as well just not sure. They all look pretty similar.

I don't have any epsom salts here but I do have a litre of Calimag. Should I add some extra and water again today to see if it improves? If it does not how do you add iron or sulphur?

 

[Nutty sKunK]

I


Thank you. I kind of thought that after I knew how much N they were getting. Never had an issue like this before. I added the proper amount of Calimag and watered yesterday.

Looking at the charts posted above it almost looks like iron, sulfer, or zinc may be an issue as well just not sure. They all look pretty similar.

I don't have any epsom salts here but I do have a litre of Calimag. Should I add some extra and water again today to see if it improves? If it does not how do you add iron or sulphur?

Those trace elements usually become a problem with an out of whack Ph.

I still stand by magnesium.

Adding cal/mag may help but calcium antagonises with magnesium.

Epsom salts are Magnesium sulphate. So you get your sulphur from there.

Blackstrap molasses has iron.

 

[cowtown]

Those trace elements usually become a problem with an out of whack Ph.

I still stand by magnesium.

Adding cal/mag may help but calcium antagonises with magnesium.

Epsom salts are Magnesium sulphate. So you get your sulphur from there.

Blackstrap molasses has iron.

Okay thanks. I will pick some up tomorrow and see if it helps.

 

[Nutty sKunK]

Thanks. I have four and two of them are yellowing from the top down. The other two are green and healthy. They get the same amount of sun, water, and feeding this is my second grow and never had this problem before and last time I grew 27 of them.

I looked at those charts you added and dont think it's an NPK issue. Been feeding with 24 8 16. I also added the proper amount of Calimag.View attachment 4385351

Edit. I fed them yesterday and the yellowing got worse this morning. Overfed maybe? Seems odd though since excess N should have the leaves a really dark green no?

More yellow this morning.

Just noticed he garden, nice!

 

[Nutty sKunK]

Okay thanks. I will pick some up tomorrow and see if it helps.

Make sure to get unsulphured molasses

 

[CanadianJim]

That doesn't really look like an iron deficiency to me, and I thought calmag had iron in it. Doesn't it have micronutrients added?