Probably a magnesium deficiency, cause unknown

[Rama777]

Yo! I have some 2.5 week old plants that were germinated in soil that was too hot. They’ll be fine eventually. Until then, I have some magnesium deficiency. Could be lack in the soil/water but it could be the plant coping with the nutrient levels in the soil in unbalanced ways. I don’t want to potentially throw anything further out of whack in the soil.

For this potential reason I’ve decided to use a foliar spray.

I see suggestions that are a bit all over the map. I like to introduce things at small/moderate levels while also of course aiming to be effective. I suppose epsom salt is epsom salt, but without several brands to test from, I don’t 100% trust that a given weight of epsom salt in solution will necessarily yield the same ppm levels.

Soooo….can anyone possibly recommend what a modest ppm target would be in solution for foliar feeding?

 

[Rama777]

Also not opposed to confirmation of symptoms or suggestions to water magnesium in instead of foliar feeding it :))

So far they have gotten just RO water with calmag at 75ppm with every watering.

As for the quality of soil, I think it’s just fine. On my last round, I started out in a more mellow starter mix and then transplanted straight into this exact same soil when the plants were about 2 weeks old with zero issues. So I really think my issues are almost entirely due to this not being an appropriate starter mix.

 

[Imzzaudae]

Your problem is that your light is to close. At lest double the distance from light.

What light do you have?
How far away from plant tops.
Power setting.

Make sure when you feed and water the pot dries out very dry between watering.
Soak well then dry right out is the key here.
Don't change anything else for at least 2 weeks.
See how the plant responds.

 

[Rama777]

Thanks man! Haven’t overwatered any in the slightest. I’ve ruled that out.

About lights, (first experience with LED) I had made the mistake of thinking that you start at 150-200 par and then increase the par gradually over the course of a few weeks. I now understand that the correct approach is to wait until closer to the 3 week mark before adjusting the intensity.

So yes, they got light stressed. However, I figured that out about 5 days ago or so. As for the magnesium deficient/light stress symptoms, they have continued to develop since getting the par right.

You think the continuation of symptoms over the last 5 days could still be a result of the light being too close up until 6 days ago?

Because it’s continuing is the reason I was suspecting that they may actually need some magnesium.

I’m certainly open to the doing nothing approach if that’s appropriate it my context.

 

[Rama777]

I did just confirm that I backed the par back off to <200 5 days ago. Possibly just a continuation of that stress? Wait it out and nothing or respond to the still developing symptoms with magnesium?

 

[Zill]

Rama,

If it is a nutrient deficiency it appears mild.

To determine absolutely if it is a Mg deficiency buy a small bag of unscented Epsom salts. One half teaspoon per 500ml spray bottle. Spray the leaves with that dilute solution. If it’s Mg deficiency the spray will clear that pretty quickly or stop it from progressing.

 

[Rama777]

Thanks, I appreciate it! I always have epsom on hand for my produce farm..

And just by the way, since Imzz did ask, my 125 watt light is over a foot away at 30%. I had it closer mistakenly earlier on. Migro recommends 10” at 40% for seedlings for this light of his. Even when my lights were too close they were never near that! He puts out a lot of informative videos so it’s a bit absurd that his recommendation would be so off. Unless I’m missing something, that would be damn near enough par for the beginning of the veg phase..

 

[Zill]

Rama,

Possibly. I’ve been sniffing around this forum for while. There are those that talk when they shouldn’t, other know nothing know it alls enhance themselves by being quite rude. not needed.

Imzzaudae speaks from experience. Maybe he can clarify. All good.

 

[Rama777]

Yeah I’ve seen that on here but for the most part the vibe is pretty positive! I guess pretty much every forum is going to have its share of assholes, just as the world has its share in general. I worked serving and bartending in restaurants for almost 20 years so…it’s gotta be one of the fastest way to discover just how many rude people are out there!

I love this forum so far :))

 

[Imzzaudae]

Hello again Rama. Thanks Zill.
After another look at your plant and reading your posts so far. I cannot see your problem being a magnesium issue as the plant is very young and you have been feeding cal-mag at 75 ppm every other watering. You say your not happy with the potting mix. What is it?

Another thing I'd like to ask is why are you using R.O water?
City or well water contain minerals the plant needs. Unless your living with very high levels of contaminants please be kind to your plants
Use city or well water. Even filtered pond water will have what your plant requires.

See the blisters on your leaf surface. And burned tips.This is light stress not a magnesium issue.
I do see a little inter venal striping but this is a light issue as well rather than a classic magnesium issue.

I have a micro grow under way, They are under a 100w led and did the same thing 2 weeks ago.
I dropped the light down to 6" for 2 days. Burned both plants.
I see your tips curling down but not burned in a couple of pictures. Feeding wise your on track.
But they do have that plump a little over watered look. It's very easy to do with young plants.

Hope this helps you.
Ron

 

[Rama777]

Yep, and really appreciate it :))

I do like the soil quite a bit, however I wouldn’t use it for initial germination again. Most of my foliage is quite dark, and I think some of the curling and twisting may be from the soil being hot as well. I did a slurry test with some of the soil out of the bag (I understand not all amendments are created equally so ppm isn’t the final story..) and got 3,000 ppm. This is my second round of growing and my first round was in a more mellow starter mix and I had zero issues with it. So, lesson learned, no biggie. Oh and the other tell that the soil is probably too hot is that the plants droop after every watering.

Of course that sounds like classic overwatering. However, though I’m new to growing pot, I start literally over 10,000 plants in flats every year for my farm. I’ve got my watering regimen down. Those all get transplanted into the field so feeding a plant throughout its life cycle in pots is definitely new to me. But yeah anyways, I started my last round of plants in the same size pots and never saw a moment of droop so I’m quite certain it has something to do with the soil, perhaps in combination with my light being too close for a week.

I’ll just keep the lights backed off to 170-200par and wait out the mag symptoms, thanks again!

 

[Zill]

Rama,

I waited tables and tended bar for years! I was a student at the University of Rhode Island and worked in Newport, RI earning money for school. I was very fortunate to be waiting tables during the America's cup race. My pockets could not hold the tips. It was crazy.

its good forum.

Thanks Imzzaudae!