Zinc & Iron For High Phosphorus Soils?

Week4@inCharge

Well-Known Member
Here's an interesting read...

"Spray foliar zinc and iron on plants in high phosphorous soils. High phosphorous levels require additional zinc and iron treatments for plants to maintain their health. Texas A&M University suggests mixing a spray that contains water with 1 percent foliar zinc and iron, then applying that spray to plants every week if phosphorous levels are excessively high. You may apply it every four weeks if phosphorous levels are slightly high. Soils with 300 parts per million phosphorous will take up to five years to go back to acceptable levels."

.

The best answer is just get it right from the beginning. but it happens, and is this a viable option for cannabis? Such a product out there would be Liquinox Iron and Zinc.

And, if there's a lockout, does a product like this even help?
 

OldMedUser

Well-Known Member
Here's an interesting read...

"Spray foliar zinc and iron on plants in high phosphorous soils. High phosphorous levels require additional zinc and iron treatments for plants to maintain their health. Texas A&M University suggests mixing a spray that contains water with 1 percent foliar zinc and iron, then applying that spray to plants every week if phosphorous levels are excessively high. You may apply it every four weeks if phosphorous levels are slightly high. Soils with 300 parts per million phosphorous will take up to five years to go back to acceptable levels."

.

The best answer is just get it right from the beginning. but it happens, and is this a viable option for cannabis? Such a product out there would be Liquinox Iron and Zinc.

And, if there's a lockout, does a product like this even help?
If Fe and Zn are blocked in the soil due to high P then a foliar spray of those should bypass that system and correct the issue temporarily. High P also blocks Ca and Mg and I don't know if some CalMag could be added to the other without causing issues like precipitation so two separate sprays would have to be used. Different days too.

How did the soil become so high in P in the first place?

:peace:
 

Week4@inCharge

Well-Known Member
If Fe and Zn are blocked in the soil due to high P then a foliar spray of those should bypass that system and correct the issue temporarily. High P also blocks Ca and Mg and I don't know if some CalMag could be added to the other without causing issues like precipitation so two separate sprays would have to be used. Different days too.

How did the soil become so high in P in the first place?

:peace:
My error with top dressing. Autos don't need that much love to prosper, Live and Grow. :) I'd rather not have the need to experiment with foilar sprays but couldn't figure out how this could work with a lock out, your answer was perfect, through the leaves!
 

MustangStudFarm

Well-Known Member
If Fe and Zn are blocked in the soil due to high P then a foliar spray of those should bypass that system and correct the issue temporarily. High P also blocks Ca and Mg and I don't know if some CalMag could be added to the other without causing issues like precipitation so two separate sprays would have to be used. Different days too.

How did the soil become so high in P in the first place?

:peace:
I've had the same problem with the compost that I was making, it was super high in potassium and phosphorus. I've been adding more Cal/Mg because soil tests have been showing that they have been low(along with the Ph).
 

MustangStudFarm

Well-Known Member
My error with top dressing. Autos don't need that much love to prosper, Live and Grow. :) I'd rather not have the need to experiment with foilar sprays but couldn't figure out how this could work with a lock out, your answer was perfect, through the leaves!
I would test your soil Ph, if it is low, I would assume that you need to add Cal/Mg. I'm assuming that you have been using some sort of compost for a top dressing. If you are using iron and zinc, you should also be using Manganese. I use all 3 because they are antagonistic with eachother.
 

Week4@inCharge

Well-Known Member
I would test your soil Ph, if it is low, I would assume that you need to add Cal/Mg. I'm assuming that you have been using some sort of compost for a top dressing. If you are using iron and zinc, you should also be using Manganese. I use all 3 because they are antagonistic with eachother.
Thanks, at the the time I was growing the autos (6months ago) I grabbed a bottle from Home Depot. Gonna have to look and actually read the label and see if anything else is in there. I'll look for this Manganese. Here's another twist to this potential low in Iron stuff .... Sulfar. Sulfar deficiency looks the exact same almost. Over feeding and/or over watering can lead to a sulfar deficiency. Tell tale signs are top leaves getting light with the green veins. (sorta sounds like a magnesium problem) but magnesium starts at the bottom, not the top.
 

MustangStudFarm

Well-Known Member
Thanks, at the the time I was growing the autos (6months ago) I grabbed a bottle from Home Depot. Gonna have to look and actually read the label and see if anything else is in there. I'll look for this Manganese. Here's another twist to this potential low in Iron stuff .... Sulfar. Sulfar deficiency looks the exact same almost. Over feeding and/or over watering can lead to a sulfar deficiency. Tell tale signs are top leaves getting light with the green veins. (sorta sounds like a magnesium problem) but magnesium starts at the bottom, not the top.
If you use products like TM7, the micronutrients are all sulfates. I have each micronutrient in sulfate form along with Gypsum(calcium sulfate) and Epsom salt(Mg sulfate). I seem to use these products often with my compost... I'll be honest, I used to overly focus on micronutrients and miss the easy stuff like Ca/Mg, but low micronutrients really is a problem. I started getting soil tests and learn how to get my "Base saturation" in the right ratio while maintaining the right Ph. I was stuck on this problem for longer than I would like to admit. I stopped using rock dust because it wasn't bringing the micronutrients like "Bro Science" promised, but then I started having Ca/Mg problems and didn't realize what they were. Again, I was hyper-focused on micronutrients. I know that I'm getting off base here, just talking it out...
 

MustangStudFarm

Well-Known Member
I started getting into Dr. Steve Solomon who is an author on soil remineralization. He admited that it would take a dump truck of rock dust(basalt I think) to get enough zinc and manganese. Kelp will give you sodium and arsenic tox before giving you enough micronutrients. I moved to using micronutrients in sulfate form. I mix mine at home and you really just need humic acid or another chelator to be like TM7 products. I was using Big-6 from Build a Soil because it was everything in TM7 but the iron. Chelators have the strongest affinity for iron, so if your iron is low, you can fix it by using a chelator alone like humic acid(lots of options here). I've been using chelated zinc and manganese to fix low iron too. If you add chelated iron, you could just throw your Zn and Mn into a tailspin. 1669948632872.png
 

Week4@inCharge

Well-Known Member
If you use products like TM7, the micronutrients are all sulfates. I have each micronutrient in sulfate form along with Gypsum(calcium sulfate) and Epsom salt(Mg sulfate). I seem to use these products often with my compost... I'll be honest, I used to overly focus on micronutrients and miss the easy stuff like Ca/Mg, but low micronutrients really is a problem. I started getting soil tests and learn how to get my "Base saturation" in the right ratio while maintaining the right Ph. I was stuck on this problem for longer than I would like to admit. I stopped using rock dust because it wasn't bringing the micronutrients like "Bro Science" promised, but then I started having Ca/Mg problems and didn't realize what they were. Again, I was hyper-focused on micronutrients. I know that I'm getting off base here, just talking it out...
Much appreciated, I'll have to look into this TM7. I'm still shooting off the hip on these grows and same thing pops up every time. Wether I feed lightly or feed heavy....same thing. In my mind I'm thinking it's probably sulfar. My water is 300-350 PPM. And that has to build up and start to block something in my pots. They need an Enema! Kinda hard to do if your growing organically like I am. So ..do I RO filter 100% ....sure am dam near tempted to on this next grow ... only way I'm gonna find out. Anyways, getting ahead of myself.... not all my pots are thinning out in color at the top. Probably just light burn...lol. Feels like I'm chasing my tail sometimes. I'm currently trying out this kelp feed stuff. Supposed to have some kind of humic acid (whatever that is) that aids in Sulphur uptake. Bro Science? It seems to be helping, my OG Kush is slowly getting some color and I've only dosed it once (last week) with several foliar sprays. Not sure if it's coincidence, they started to grow out some pistils a few days after that initial soil drench.
 

Week4@inCharge

Well-Known Member
I started getting into Dr. Steve Solomon who is an author on soil remineralization. He admited that it would take a dump truck of rock dust(basalt I think) to get enough zinc and manganese. Kelp will give you sodium and arsenic tox before giving you enough micronutrients. I moved to using micronutrients in sulfate form. I mix mine at home and you really just need humic acid or another chelator to be like TM7 products. I was using Big-6 from Build a Soil because it was everything in TM7 but the iron. Chelators have the strongest affinity for iron, so if your iron is low, you can fix it by using a chelator alone like humic acid(lots of options here). I've been using chelated zinc and manganese to fix low iron too. If you add chelated iron, you could just throw your Zn and Mn into a tailspin. View attachment 5232859
woah... gonna have to read this again, thanks. (Gonna try some of the Big-6, they take forever to ship though)
 
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BongerChonger

Well-Known Member
My error with top dressing.
Bang on the money there, I think.

Too much PK in organic soils is mostly caused by too much rich organic matter. Too much rich matter will cause compaction overtime also.
Need to be adding a lot more browns when you're composting your soil, so it helps against compaction. By forming clumps, thus improving aeration and drainage.

Excess needs to be able to drain. Or, be bulked out with other materials.

Almost everything to do with organic soil health is aeration related. That I am more than confident to say.
Everything from texture, to E.C., to fertility, even pH (potential hydrogen) are all dependant to some degree, on the aeration and porosity of your soil.

edit: a good source of zinc maybe chalk dust?
a good source of iron is anything leafy and green, or anything bloody.
 
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Week4@inCharge

Well-Known Member
Bang on the money there, I think.

Too much PK in organic soils is mostly caused by too much rich organic matter. Too much rich matter will cause compaction overtime also.
Need to be adding a lot more browns when you're composting your soil, so it helps against compaction. By forming clumps, thus improving aeration and drainage.

Almost everything to do with organic soil health is aeration related. That I am more than confident to say.
Everything from texture, to E.C., to fertility, even pH (potential hydrogen) are all dependant to some degree, on the aeration and porosity of your soil.

edit: a good source of zinc maybe chalk dust?
a good source of iron is anything leafy and green, or anything bloody.
I'm playing a new card with this, I'm going with the idea that they are not liking the saw dust mulch layer, I originally added it to absorb as much nitrogen from the soil as they could, my leaves were too dark (green) to my liking. Now that things are under control, the Kush (and one Northern Lights) are hungry. I have been procrastinating changing the mulch layer out but I did that last night. I took out all the mulch layer and added a fresh layer of compost. So we will see. before all that I started to add more cal mag (w Iron) and that seems to have brought them back a little. not 100% healthy as my other girls but considering what they've gone through, they're doing good.
IMG_20221206_081833_082.jpg
 

BongerChonger

Well-Known Member
I'm playing a new card with this, I'm going with the idea that they are not liking the saw dust mulch layer
Maybe...I haven't ever used sawdust as a mulch layer really. Besides obviously woodchips and the like.
Think it might not be the sawdust, but the type?
Sure wood mulch can sap nitrogen from your soil, if the wood's a little fresh. But was it more a case of any beneficial microbes not liking the specific wood that much? Fair question to ask.

A good mulch layer should be producing nitrogen, because of all the microbial activity underneath.
Something like Pea Straw, Sugar-cane etc would be ideal.

Not knocking your garden at all when I say, I think the soil front left of photo, would benefit from some brown material before the next run.
Looks very rich. Just needs some spongeyness.

Anyway, I wasn't really intending for my comments to be straight advice.
Be cool to see if you're correct.

Good luck.
 

Week4@inCharge

Well-Known Member
Maybe...I haven't ever used sawdust as a mulch layer really. Besides obviously woodchips and the like.
Think it might not be the sawdust, but the type?
Sure wood mulch can sap nitrogen from your soil, if the wood's a little fresh. But was it more a case of any beneficial microbes not liking the specific wood that much? Fair question to ask.

A good mulch layer should be producing nitrogen, because of all the microbial activity underneath.
Something like Pea Straw, Sugar-cane etc would be ideal.

Not knocking your garden at all when I say, I think the soil front left of photo, would benefit from some brown material before the next run.
Looks very rich. Just needs some spongeyness.

Anyway, I wasn't really intending for my comments to be straight advice.
Be cool to see if you're correct.

Good luck.
thanks, the 3 pots pictured were just done last night with compost. I might add some straw as suggested. Pea straw.. that's a new one for me, I'll have to look that one up, thanks for the advise my friend. And yes, that left side pot got the bottom of the bag compost, it was very wet....good eye.
 
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