Magnesium def how to handle

Hey people,

I have a few plants who are getting what I think is a mag def. Pics are attached if you think it's something different let me know please.

I have been battling this since using LED lights and coco and I'm thinking I need to up the feed. I have foliar fed epsom Salts and rhizotonic and will continue every 3rd day to feed like that. I also raised the temp as this has been identified as a possible cause for the issue.

I have been feeding at 1.2 ec with 0.4 starting water. I'm about to try and up the dose to about 2.0 with increases over a couple of feeds. This pheno is a monster and grows so quick so I'm thinking it's hungry but does anybody think flowering plants with issues this bad are worth flowering?

Does anybody think continuing the foliar and upping the EC is the right path forward?

A little stoned so if you need any more info please just ask. Any input would be appreciated!

How often do you feed every day?

They look bone dry and that's a big NO NO growing in Coco coir.

Never let the surface dry out and feed at least two times a day and the plants will recover.

It's not that they're being fed to light solution, they're not being fed often enough and being treated like soil grown plants instead of hydro grown plants that Coco Coir is.

These pots are eleveated to be able to not sit in runoff hence they're designed to stay constantly wet with added aeration.

Wastei said:

How often do you feed every day?

They look bone dry and that's a big NO NO growing in Coco coir.

Never let the surface dry out and feed at least two times a day and the plants will recover.

It's not that they're being fed to light solution, they're not being fed often enough and being treated like soil grown plants instead of hydro grown plants that Coco Coir is.

These pots are eleveated to be able to not sit in runoff hence they're designed to stay constantly wet with added aeration.

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Thanks for getting back to me buddy atm it's once per day but the other day I did split the feed into two doses but that was only one day.

That's interesting about the feeding twice. I was thinking that. Do you think twice with a low dose or does it not matter?

The canna people emailed me and said I should not get run off with the canna A+B which is why I havnt but I guess I can just water a little bit again and figure how much will be too much.

I agree with the above post, they look very dry and hungry. Varigation on leaves happens just keep a closer eye on them as you up the feed and watering as advised. Growing in Coco requires some runoff to measure your EC, if it was soil, no runoff is needed.

FatBoyVik said:

Thanks for getting back to me buddy atm it's once per day but the other day I did split the feed into two doses but that was only one day.

That's interesting about the feeding twice. I was thinking that. Do you think twice with a low dose or does it not matter?

The canna people emailed me and said I should not get run off with the canna A+B which is why I havnt but I guess I can just water a little bit again and figure how much will be too much.

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I always recommend to not listen to sales reps, they're just after your money.

General recommendations in Coco coir asks for 10-20% runoff at every feeding. When you've learned a little bit more about the plant you're growing you can start dialing in and lower strength with less runoff. You need to properly cycle the medium to keep pH and EC in check growing in Coco Coir.

OK looks we know what to moving forward. Cheers gents!

In my experience usually with coco and led's the problems come down to some combination of a not hot enough grow room & leds set too powerful. Perhaps try adding some heat & cal mag and see what happens.

Coco basics:
Feed daily to substantial run off every time........multiple feeds per day is good.
The pH should be around 6.0.
Never use plain water and never let the coco dry.
It looks like you could use better lighting........the plants are stretched and spindly.
There is no need to increase nute strength as long as you feed properly.

lungbutter said:

In my experience usually with coco and led's the problems come down to some combination of a not hot enough grow room & leds set too powerful. Perhaps try adding some heat & cal mag and see what happens.

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Yeah exactly it's been a real eye opener as I had loads of grows under my belt with hps and never had any of these issues. Though I was also in soil.

MickFoster said:

Coco basics:
Feed daily to substantial run off every time........multiple feeds per day is good.
The pH should be around 6.0.
Never use plain water and never let the coco dry.
It looks like you could use better lighting........the plants are stretched and spindly.
There is no need to increase nute strength as long as you feed properly.

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Yeah I turned the lights down as somebody said too much light could cause it to eat up more mag or something. I'll turn it up soon once it's settled and it's had more frequent feedings.

The trick with coco is it needs to be prebufferd with cal mag before use.
Simply put coco is like sponge to cal mag and pre buffering fills these holes
Even if it says it's bufferd do it anyway.
Always water to ample runoff.
With the Canna line you should use Canna Coco A B

Mix epsom salt into solution and then drench. If you're in coco coir, the issue is that coco needs more calcium and magnesium and this is how to address it. I recommend you drench with nutrients containing calcium separately until you've had a chance to read up on calcium vs sulphur interactions.

What are you temps? Cold temps stop calcium from being absorbed and translocated.

If you've not been feeding to run off that's your problem I'd say, here's how to know.
Feed the plants enough to get a decent amount of run off and test the ec/ppm, without run off you can be certain it's too high.

To fix it feed/rinse the pots with weak nutrient (1/4 strength) untill the run off is below your target ec, then feed them with 1.2/1.4ec ph6.0 ideally twice a day.

When I grew in coco last summer , I had to hand water 4x a day for best results - outdoors . My climate is relatively mild - indoors I’m a big believer in sips , dwc, micro drip , ebb and flow - basically any system to keep things saturated and on schedule . If it’s from your lights - the center of the tent , and the highest points on the plants in the center - will show the symptoms the worst - lower lying branches and outer edges will look much better .

You are likely to have issues with magnesium if your soil, or nutrient contains high levels of potassium, ammonium (NH4) or calcium.

Said already, coco may be bonding with your mag. But you'd more than likely have a cal deficiency along side it. I'd suspect your pH is outta wack or you have an excess of the elements i mentioned.

MPGrowdude said:

The trick with coco is it needs to be prebufferd with cal mag before use.
Simply put coco is like sponge to cal mag and pre buffering fills these holes
Even if it says it's bufferd do it anyway.
Always water to ample runoff.
With the Canna line you should use Canna Coco A B

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Yeah I buffered the bricks I get let them soak in cal mag for like 8 hours.

GreenGenez421 said:

You are likely to have issues with magnesium if your soil, or nutrient contains high levels of potassium, ammonium (NH4) or calcium.

Said already, coco may be bonding with your mag. But you'd more than likely have a cal deficiency along side it. I'd suspect your pH is outta wack or you have an excess of the elements i mentioned.

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Good call I checked the ph meter and it was off by 4 points!

Jjgrow420 said:

What are you temps? Cold temps stop calcium from being absorbed and translocated.

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Temps are about 25c 27c

FatBoyVik said:

Good call I checked the ph meter and it was off by 4 points!

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That's why I use the drops........cheap and never wrong.