Magnesium (Mg) deficiency? Pics

[Opie Yutts]

As best as I can tell from checking the two links below, one of my mothers to be has an Mg deficiency. The leaves feel hard and brittle. The yellowing, which turns brown starts at the tip mostly, but also the outer edges. I doubt it matters, but this is the same plant that is in with the shrooms in this post: http://boards.cannabis.com/plant-pro...ooms-weed.html. It starts in the older leaves, and eventually the bottom ones turn completely brown. There is interveinal chlorosis, and it's growing really, really slow.

The two places I checked are here:
Grow Marijuana FAQ, Cannabis cultivation - marijuana growing tips & photos

and here:
114 Photos of Mineral Deficiencies in Plants (~ 1 meg) for Visual Diagnosis

This last one is really cool. Less people know about it, but it may be more helpful. Just use your browser's search feature to search the page for individual minerals, like say magnesium, and you get between 10 and 25 examples (of stuff other than pot) of that deficiency or surplus. I suggest people bookmark both links, and maybe even make them available offline incase they ever go away.

I really don't want to lose this mother. Please help.

Opie Yutts Reviewed by Opie Yutts on 09-20-2007. Magnesium (Mg) deficiency? Pics As best as I can tell from checking the two links below, one of my mothers to be has an Mg deficiency. The leaves feel hard and brittle. The yellowing, which turns brown starts at the tip mostly, but also the outer edges. I doubt it matters, but this is the same plant that is in with the shrooms in this post: http://boards.cannabis.com/plant-problems/134279-shrooms-weed.html. It starts in the older leaves, and eventually the bottom ones turn completely brown. There is interveinal chlorosis, and Rating: 5

[the image reaper]

I recently had a Willie Nelson do that on me ... whether I diagnosed it correctly, or not, I don't know ... I treated it like a nitrogen overdose, and flushed the hell out of her ... she recovered quite a bit, but it took the whole last month of flowering to do so ... good luck, I don't think that is a magnesium problem, though ... :smokin:

[the image reaper]

only the one plant did that, the others were fine, and happened virtually overnite ... I suspected, perhaps I didn't have my nutes mixed well enough, and it got a 'hot dose' ... that is only speculation, though ... :smokin:

[Ganja Guerrilla]

do you spray your plants? foliar feed?

I believe you have a ph lockout, magnesium, calcium & more
no matter whats locked out its why.

complete a soil runoff PH test.......
with PH corrected water (6.5-6.8PH ) pour enough water in the pots so the water runs out the bottom of the pot ...collect & test the PH of this runoff water....post both the watering going in the pots and the runoff ph

[Opie Yutts]

I don't foliar feed. The soil run off if 6.7. The water going in is 6.8. Should I foliar feed until she gets back on track? If so, with what exactly?

[the image reaper]

I don't know exactly what happened to my single plant, but after flushing, I just gave her plain water, and she did start recovering shortly before finishing ... never had one do that before, or since ... :smokin:

[stinkyattic]

What are those mottled track-looking things on the leaves?
I can't really tell from those pics but at first glance I thought EXTREME thrip infestation. That would also cause dehydration damage to your leaves.
A mist of neem oil will help keep them from losing any more moisture, and slow the thrips.
Can you get better pics of the leaf surface though to make a diagnosis?

[Opie Yutts]

Ok, hold on for more pics. I'll see what I can do. I got macro, but it aint the best.

[Opie Yutts]

Image reaper, I'm leaning toward doing just what you did. I think I'll flush, then give her just water for a couple weeks, then real weak nutes to start. I suppose it's possible that she could be getting nute burn. I have kinda been giving them a lot of food, but other varieties in identical conditions are thriving nicely. Perhaps it's a PH lockout as Ganja suggests. (I assume this is the same thing as nutrient lockout.) Looks more like burn though. Looks even more like Mg deficiency if you try to find it in the two links I posted above.

[Opie Yutts]

What are those mottled track-looking things on the leaves?

I'm certainly not an expert, but from reading those two problem charts above I'd say it's interveinal chlorosis. Not even exactly sure what that is, but it looks kinda like the examples.

I can't really tell from those pics but at first glance I thought EXTREME thrip infestation. That would also cause dehydration damage to your leaves.

Dehydration damage to the leaves is a good way of describing how they feel. How can this happen if the plant is being watered properly? Does lockout cause brittle leaves (never had it before)? I am fairly certain the problem is not an extreme thrip infestation, or even a small one. I have never had thrips, and I searched the plant and soil for them with a magnifying glass and didn't see any, or anything else that was moving. Also other mothers are touching the container that the problem plant is in, and they have no thrips.

A mist of neem oil will help keep them from losing any more moisture, and slow the thrips.

I stopped using neem oil about three years ago, but I think I have some around here under one of the piles of crap. But you're saying it would be benificial to dig it out, even though I argueably have no thrips? I've never heard of neem oil inhibiting moisture loss, but again, I'm no expert. How about foliar feeding; does that have about the same effect, only with nutrients?

Can you get better pics of the leaf surface though to make a diagnosis?

Absolutely, here you go. I appreciate you helping me very much. I would be happy to help you help me. This as close as my macro will get me. And you are probably already aware of this, but unless you have a huge screen you are not seeing my pictures at full size, and they may be enlarged in your browser.