Correcting Mg Deficiency, Day 30 Flower

koalajesus

Active Member
Hello all,

Just had a quick question I was hoping to get assistance with.

I'm positive my plants have an Mg deficiency and it's getting into the later stages.
I attached some photos showing the damage. All the leaves are either starting the yellowing on the edge of have progressed to the yellowing with burn dots, or even burnt tips.

Growing in coco/perlite mother earth mix.
Using DynaGro nutrient lineup, ProTekt, FoliagePro, Bloom, and MagPro.
DynaGro uses calcium in their Foliage Pro/Bloom macros then you add MagPro to complete the micronutrient requirements.
I do use RO water and attempt to follow the feed chart at 75% the recommended doses.

Started at about 750-780ppm and have been slowly going up in MagPro and Bloom.
Current feed is 905ppm, 5.9pH, 1.2 EC.
Fed once a day at 15 second on/45 second off intervals for 8 minutes.
Runoff comes out at 1050ppm, 1.5EC

I'm still thinking about going more on the ppm and using 100% of the recommended. However, I wanted to know if I should rinse my current media, then a light watering of 100% feed or just full send the feed without a quick rinse.

Thanks for the input!!
 

Attachments

koalajesus

Active Member
Looks more like nute burn or potassium def. hard to tell. Not seein mg def.
I definitely know it's a deficiency. It started very light yellow and hungry looking, but it's progressed over the past 5-6 days. Might be burning up now from lockout (hence the advanced deficiency) as I did bump the feed day by day.

I was using https://www.royalqueenseeds.com/blog-magnesium-deficiency-in-cannabis-plants-n590 in my search for references to deficiencies and either I'm blind or Mg does match some of my leaves pretty well.

I will say though, tabbing over to K on the same link at the top of the page, they look pretty similar to Mg problems. Just looks like the brown/rust/burn spots end up in a different pattern, more along the tip for K versus spots for Mg.

Unless the website has it wrong and I'm just being ignorant.

I did take action though cause I had to water. Rinsed out the pots with some RO, bumped the feed again to 950. Waited a little bit for the pots to fully stop dripping, then watered just in small amounts until a bit of run off.

Hoping this works. They still look good for the bud sites and they're smelling great. Just trying to finish without killing 'em.
 

koalajesus

Active Member
Not sure where you looked to see Mg leaf symptoms, but that it ain't.
I agree w/ hydrodan, your leaf is a poster child for a K deficiency

Mg deficiency generally looks like this:
View attachment 5120178
I cited above in my previous reply where I was getting references for the deficiencies.

But I should know better than to just check one site and roll with it. I've seen the same symptoms when searching for Mg deficiencies online as the one you've provided and others showing K being more similar to mine when just peeling through Google images.

So just my pure ignorance. I'll just hope that upping the dose will work out. I'm not raising just the MagPro alone, I've been raising the Bloom (main K macro nutes) as well so hopefully things will get better.

Consider the thread closed. Thanks guys.
 

Wastei

Well-Known Member
Hello all,

Just had a quick question I was hoping to get assistance with.

I'm positive my plants have an Mg deficiency and it's getting into the later stages.
I attached some photos showing the damage. All the leaves are either starting the yellowing on the edge of have progressed to the yellowing with burn dots, or even burnt tips.

Growing in coco/perlite mother earth mix.
Using DynaGro nutrient lineup, ProTekt, FoliagePro, Bloom, and MagPro.
DynaGro uses calcium in their Foliage Pro/Bloom macros then you add MagPro to complete the micronutrient requirements.
I do use RO water and attempt to follow the feed chart at 75% the recommended doses.

Started at about 750-780ppm and have been slowly going up in MagPro and Bloom.
Current feed is 905ppm, 5.9pH, 1.2 EC.
Fed once a day at 15 second on/45 second off intervals for 8 minutes.
Runoff comes out at 1050ppm, 1.5EC

I'm still thinking about going more on the ppm and using 100% of the recommended. However, I wanted to know if I should rinse my current media, then a light watering of 100% feed or just full send the feed without a quick rinse.

Thanks for the input!!
Way overfed, they look almost blue instead of green and not showing developed Mg def, maybe slight. I bet K def from excess N. What scale do you use for ppm? Most people use and prefer the 0.5 scale, maybe you're on the 0.64 scale? I think your nutrient strength is off.

Don't use 100% of recommendations, you're already burning your plants. Buy some epsom salt instead of Mag Pro.
 

koalajesus

Active Member
Way overfed, they look almost blue instead of green and not showing developed Mg def, maybe slight. I bet K def from excess N. What scale do you use for ppm? Most people use and prefer the 0.5 scale, maybe you're on the 0.64 scale? I think your nutrient strength is off.

Don't use 100% of recommendations, you're already burning your plants. Buy some epsom salt instead of Mag Pro.
Just saw this as I kinda abandoned this thread and overall help from the internet as I get varying information and it's been fucking with my head too much, so I'm just rolling with my gut to be honest. I don't think they're way overfed, but overfed in N causing some issues with K uptake, agreed.

For ppm scale, I originally posted that I was at 75% (0.75), but I probably was closer to .65-.7. I upped the feed though and removed a lot of the damage. The issue hasn't pursued as aggressively as it was if at all. One plant is still struggling a bit, but the others seem to have liked a bump in feed.

Once again, I do agree in the overdose of N, a result of me puting some of the main N formula (Foliage Pro) in the water mix. That has been removed for some time, but this deep in flower, all that N went to darkening the leaves and no growth. Can't really change it at this point. All part of the learning process.

I appreciate the advice and I'll look into the Epsom salt. I'll be honest I have quite a bit of the MagPro so I'm gonna try to make it work so it wasn't just a money loss.
 

Star Dog

Well-Known Member
Just saw this as I kinda abandoned this thread and overall help from the internet as I get varying information and it's been fucking with my head too much, so I'm just rolling with my gut to be honest. I don't think they're way overfed, but overfed in N causing some issues with K uptake, agreed.

For ppm scale, I originally posted that I was at 75% (0.75), but I probably was closer to .65-.7. I upped the feed though and removed a lot of the damage. The issue hasn't pursued as aggressively as it was if at all. One plant is still struggling a bit, but the others seem to have liked a bump in feed.

Once again, I do agree in the overdose of N, a result of me puting some of the main N formula (Foliage Pro) in the water mix. That has been removed for some time, but this deep in flower, all that N went to darkening the leaves and no growth. Can't really change it at this point. All part of the learning process.

I appreciate the advice and I'll look into the Epsom salt. I'll be honest I have quite a bit of the MagPro so I'm gonna try to make it work so it wasn't just a money loss.
Taking guessing out of the equation...
run 1.0ec nutrient through your coco and measure the run off then you'll know for sure.
If you do measure the run off let us know what it is?
 

koalajesus

Active Member
Taking guessing out of the equation...
run 1.0ec nutrient through your coco and measure the run off then you'll know for sure.
If you do measure the run off let us know what it is?
I guess "going with my gut" is a bad term to use because I am still taking measurements and acting based on results and not just throwing things together.

Currently, as of last feed at 1.6 EC, runoff came out at 2.1 EC. The runoff is increasing in EC as the days go, so I do know the excess nutrients is occurring. My next feed was planned to be lower, about 1.2 EC, but it sounds like this is too high of a feed based on the current conversation. Next steps is probably to flush out the pots real well, give a light feed at maybe .5 EC, then bring it back to 1.0 EC after it dries up a bit.
 

Star Dog

Well-Known Member
I guess "going with my gut" is a bad term to use because I am still taking measurements and acting based on results and not just throwing things together.

Currently, as of last feed at 1.6 EC, runoff came out at 2.1 EC. The runoff is increasing in EC as the days go, so I do know the excess nutrients is occurring. My next feed was planned to be lower, about 1.2 EC, but it sounds like this is too high of a feed based on the current conversation. Next steps is probably to flush out the pots real well, give a light feed at maybe .5 EC, then bring it back to 1.0 EC after it dries up a bit.
You're on the right track now, I would rinse it down then feed it 1.0 and keep an eye on the plant and ec, if it keeps rising lower it again if its coming out lower than going in raises it until you find the happy medium.
 

koalajesus

Active Member
You're on the right track now, I would rinse it down then feed it 1.0 and keep an eye on the plant and ec, if it keeps rising lower it again if its coming out lower than going in raises it until you find the happy medium.
Radical. Luckily, only one plant out of the five is struggling at this moment. The rest seem to still be putting up with what I've been giving, but I'll still make the changes so I can finish these last few weeks.

Appreciate the advice!
 

PadawanWarrior

Well-Known Member
Radical. Luckily, only one plant out of the five is struggling at this moment. The rest seem to still be putting up with what I've been giving, but I'll still make the changes so I can finish these last few weeks.

Appreciate the advice!
That's like totally radical bro, :lol:

Just playing man. :bigjoint:
 
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