What is this?

[cornflake]

As it progresses the spot where the coloration is dries right out, completely, like this

I think it's related to drying out, too much exhaust in my veg cab, and too much fan heater. But the leaves don't turn up at edges like it's a heat issue.

Seen it before?

 

[Weedninja]

Looks like a mag deficiency.

 

[chubbynugs]

Yeah that does look like a Mg deficiency. Flush with a fert mix with enough Mg.

 

[cornflake]

Thanks guys, will check back soon

 

[Kinderfeld]

add a little Epsom salt if you don't have any cal mag, it will fix right up...

 

[cornflake]

I think it's Boron Deficiency not Mag, going by pics from Mynamestitch's sticky pictures.

His pics...

Mine...

Although one of his pics show damage to leaf tips that would be because of continued deficiency, whereas mine appear to have been in trouble at some point but has recovered.

Looks to me much more like Boron than Mg, def.

Agreed?

 

[Weedninja]

Notice that on Stitch's pics the damage is to the new growth? Now look at your pics. The damage is in the older growth. That's because Mg is a mobile element, which means that the plant can pull it from the older leaves to feed the new growth. Boron is immobile, which means that the plant can't move it, so new growth suffers. Mg deficiencies are also much more common.

 

[Nathindica]

is that coco you're growing in? ever grown in it before? some people say its easier to get cal/mag problems in coco because of the medium's natural tendency to absorb calcium. using cal mag at all?

got that from this thread...
http://www.icmag.com/ic/showthread.php?t=100435

im a new grower so let others chime in before you take any of my advice... I've just read through a shitload of threads on this site in the quest for knowledge. But nothing compares to experience.

BUT. i could be all wrong. is that even coco?

 

[Nathindica]

sorry. smoking too much. you have a mg deficiency. don't know why i was going on about cal. looks like i'll keep my mouth shut a little while longer haha.

 

[cornflake]

add a little Epsom salt if you don't have any cal mag, it will fix right up...

I'm using canna coco hydro nutes.

So a little epsom salts? How much per litre? plz

 

[bigjay]

one table spoon per gal

 

[GreenDream]

Looks like Mg deficiency, but probably not because there's not enough Mg in your soil....

Mg is easily locked out by high salt levels (NaCl) and coco is notorious for having excess salt due to it coming primarily from coastal regions.

Your best bet would be to foliar feed with the epsom salts while leeching the coco. Once the coco is purged of excess salt, you can then resume your regular feeding program.

 

[cornflake]

Looks like Mg deficiency, but probably not because there's not enough Mg in your soil....

Mg is easily locked out by high salt levels (NaCl) and coco is notorious for having excess salt due to it coming primarily from coastal regions.

Your best bet would be to foliar feed with the epsom salts while leeching the coco. Once the coco is purged of excess salt, you can then resume your regular feeding program.

I've been growing in canna coco for a couple of years now and here's a newsflash, they don't have salt in their coir, that's what happens when you use cheap coir.

I flush every 3rd watering to remove excess salt buildups, it isn't that.

But thanks for being there.

 

[GreenDream]

I've been growing in canna coco for a couple of years now and here's a newsflash, they don't have salt in their coir, that's what happens when you use cheap coir.

Here's another news flash- nobody is perfect, including canna. We have seen bad batches come from nearly every substrate manufacturer. All I am saying is don't discount the fact that your coco may have excess NaCl just because you paid out the ass for it!

I flush every 3rd watering to remove excess salt buildups, it isn't that.

By salt I mean NaCl; not what you're feeding them. My main point still remains; try foliar feeding the epsom. Not only will it work better, but you will see results sooner.

Good luck bro~ hope you figure out the prob!

 

[Kindman69]

Well, sice I'm the 'off-gassing' crusader I always I always ask this question first when I see a progressing mg problem. Are you growing in a tent or are there any newly added materials in your grow cab? If not, blessed you are and you will just have to deal with a lockout. If yes, take a plant out of the space and see if it gets back on track on its own. If yes, you will have to do some work on your grow cab and you can check the 'off-gassing' thread
It does not look definitive to me yet.

Kindman

 

[cornflake]

Here's another news flash- nobody is perfect, including canna. We have seen bad batches come from nearly every substrate manufacturer. All I am saying is don't discount the fact that your coco may have excess NaCl just because you paid out the ass for it!



By salt I mean NaCl; not what you're feeding them. My main point still remains; try foliar feeding the epsom. Not only will it work better, but you will see results sooner.

Good luck bro~ hope you figure out the prob!

Hey GreenDream, thanks for inputing ideas and I can see, experience.

I hear ya bro', I'm on a 3rd re-use of the coco, it's last round and it's not from new coco with residual salt.

I understood you meant the salt buildup as a result of regular feeding, not that I add salt hehe

That's why I offered that I flush with 6.0 rainwater every 3rd feed, to prevent salt buildup. It works.

I will apply the epsom via foliar spray, thanks for advice.

It's probably a lockout, I've only got a cheap drop test kit, nothing too accurate. I've been considering a few and will buy something better soon.

I've only seen the discoloration once or twice and it's during veg so not too worried. thanks for all inputs.

Also thanks Kindman, it's not outgassing.