[HELP] Narrowed Down To Nitrogen Toxicity

[Puddentane]

I can tell you one neat little trick to watering out excess salts without facing the dreaded stagnant soils that come with it. Saturate your soil to the point of run off and then get a brick or other item and prop the plant sideways 30-45 degrees. This decreases the water column drastically and cause a large volume of water to drain out. No mater the angle of the pot, the water table wants to remain level due to gravity so the volume excluded from that zone is the volume you will see released from the potting mix. You can turn the plant 180 to further drain it out. Once the process is finished (anywhere from 30 minutes to several hours) You can level the plant and it will redistribute the water throughout the soil profile. This is a great method of pulling air into a water logged pot provided you do not damage your plants or loose soil from the top.

This trick will allow you to really put the water to a soil that is out of balance to try to bring her back to a more stable state. Tap water is fine for this although I usually try to follow up with a final application of aged tap if it is something sensitive. I have done this several times over the period of a couple of days to take the pressure off shrubs and trees in the nursery.

Disclaimer: Cannabis is a relative new crop for me so there are going to be some differences in performance. But the science is sound. So Keep that in mind.

 

[Waira]

What's all this rambling ruckus about o'er here!? @Yeatster..Ray-ed!! I shudda figur'd...

>> Santorini-- pics tell me this:
-- N-tox looks older, and isn't really the issue here now,...
-- current symptoms smack of a couple deficiencies,.. any nute's added at all? MG soil is anything but complete,... and generally too hot (and N rich as you see!),... rapid yellowing like this can also indicate a possible off-pH in the soil... Looks like some Mg defc. (interveinal yellowing starting in before watering Sun. pics), maybe some S defc. starting as well in the after-pics (yellowing at the newest growth/tops).. maybe P getting started too, making for that overall paleness that gets muddied with the S defc. symptoms...
--- Question is, if this is an off-pH lockout happening, or a simple lack-of type defc.'s,... do you have a pH meter? here's the catch: if it's an off pH deal, adding nutes will likely make matters worse, as uptake is compromised already, and more feeds will worsen pH most likely (usually feeds are acidic) ... my guess is the soil is too acidic, and you might have lack-of defc.'s as well,...pending your feeding, if any!
-- using distilled or RO water isn't the best choice, despite the purity,.. it has no pH buffering minerals in it (CaCO3) like most tap does, and because of that the pH of the water or nute. solution will swing wildly from even small inputs! If the soil doesn't have enough built in buffering from a lime source, the problem will be even worse and persistent,..
-- mind what Yeats' and Red say about even watering, besides, the MG soil has been tapped into pretty hard by now, so it's not so hot per se at this point,...
-- stay clear of any MG soils, especially nute pre-loaded ones! poor quality and bad nutrient balancing in them for canna',.... As for soils, unless you can test that bag before use, stay clear of their soils as well,.. many problems with soils being badly acidic (talkin' in the low 5's here! ), undercooked shite....
-- get an Accurate 8 soil pH probe, and forget the cheapie skinny probes you see at garden centers, etc.,.. they're crap!

..dealing with your soil will depend on what you say about feeding, other inputs (Mammoth is an inoculant of specialized bacteria, geared toward P turnover... Likely, as Red mentioned, a serious watering is a start, just to make sure the soil is evenly moistened top to bottom,.. a flush with 2-3x pot volume might be next, using water with some mineral hardness in it to help with pH buffering,.. if you flush, you'll need to use a weak nute solution on the last pour, so you don't trigger a mass defc. panic in the plant,...

 

[Yeatster]

What's all this rambling ruckus about o'er here!? @Yeatster..Ray-ed!! I shudda figur'd...

>> Santorini-- pics tell me this:
-- N-tox looks older, and isn't really the issue here now,...
-- current symptoms smack of a couple deficiencies,.. any nute's added at all? MG soil is anything but complete,... and generally too hot (and N rich as you see!),... rapid yellowing like this can also indicate a possible off-pH in the soil... Looks like some Mg defc. (interveinal yellowing starting in before watering Sun. pics), maybe some S defc. starting as well in the after-pics (yellowing at the newest growth/tops).. maybe P getting started too, making for that overall paleness that gets muddied with the S defc. symptoms...
--- Question is, if this is an off-pH lockout happening, or a simple lack-of type defc.'s,... do you have a pH meter? here's the catch: if it's an off pH deal, adding nutes will likely make matters worse, as uptake is compromised already, and more feeds will worsen pH most likely (usually feeds are acidic) ... my guess is the soil is too acidic, and you might have lack-of defc.'s as well,...pending your feeding, if any!
-- using distilled or RO water isn't the best choice, despite the purity,.. it has no pH buffering minerals in it (CaCO3) like most tap does, and because of that the pH of the water or nute. solution will swing wildly from even small inputs! If the soil doesn't have enough built in buffering from a lime source, the problem will be even worse and persistent,..
-- mind what Yeats' and Red say about even watering, besides, the MG soil has been tapped into pretty hard by now, so it's not so hot per se at this point,...
-- stay clear of any MG soils, especially nute pre-loaded ones! poor quality and bad nutrient balancing in them for canna',.... As for soils, unless you can test that bag before use, stay clear of their soils as well,.. many problems with soils being badly acidic (talkin' in the low 5's here! ), undercooked shite....
-- get an Accurate 8 soil pH probe, and forget the cheapie skinny probes you see at garden centers, etc.,.. they're crap!

..dealing with your soil will depend on what you say about feeding, other inputs (Mammoth is an inoculant of specialized bacteria, geared toward P turnover... Likely, as Red mentioned, a serious watering is a start, just to make sure the soil is evenly moistened top to bottom,.. a flush with 2-3x pot volume might be next, using water with some mineral hardness in it to help with pH buffering,.. if you flush, you'll need to use a weak nute solution on the last pour, so you don't trigger a mass defc. panic in the plant,...

This^^^ is exactly what I meant to say.