Deficiency or Toxicity? Here's a few pic & info...

[Danked]

Ok, so... I've got a 4x4 DIY growbox, 1000w, temp/humidity is straight (75 day/65 night, ~40-50

% RH). I've got 4 plants in there right now, 4 different strains, all 8-10 week strains (and unfortunately all are on the same feeding schedule). I grow in a coco coir/growstone/perlite mix (80/10/10). I'm running House & Garden coco nutes for the first time, with some of their additives + Sea Green and H16 Finish. I'm also using RO water and adding ~3ml/gal GH Calimagic (~100-150ppms) before mixing anything in. I'm about 18 days into flowering, and all of them have been super healthy and chuggin' right along, except these past few days I'm starting to see signs of something going on with my Green Crack (GC) plant. Its the fan leaves towards the top of the plant that are starting to kind of 'fade' slightly, and they're starting to get a weird brownish, rustyish looking spots. I know that sounds like a calcium def. right away... But I've tried correcting that, and I've also dealt with that a few times in coco, and I really don't think that's what it is. I've checked the PPM's of the run-off, and they're 100ppms lower than any of the other plants, so I don't think it's salt build-up either. Just to flush it a little anyway, I hit it yesterday with about 3-4 gallons of RO + some Calimagic & 25% base nutes (~0.7 EC, 350 PPM's) to pull some build-up out (it's only in a 2gal pot). ANY suggestions or help would be appreciated. The plant itself is still doing really well despite the discoloration. I just want to catch/correct any problems before I get too far into flowering. Thanks - danked

 

[Seamaiden]

Looks like new growth, looks like a classic Ca- to me. Stop using the combination product, you'll never correct a Ca- by using calcium and magnesium. Like, ever. Get yourself a Ca-only product and Epsom salts, divide up the Ca from the Mg feedings. Start giving both a foliar and root feed of Ca @ double the recommended rate (assuming this is a product with around 3%-6% Ca), and use the Mg as either a foliar or a root feed starting at a rate of about 1/4tsp (1g) per gallon of water.

You're gonna be chasing your tail on the Ca-, but you should be able to stop it from progressing to the point of impacting yield.

 

[Danked]

Looks like new growth, looks like a classic Ca- to me. Stop using the combination product, you'll never correct a Ca- by using calcium and magnesium. Like, ever. Get yourself a Ca-only product and Epsom salts, divide up the Ca from the Mg feedings. Start giving both a foliar and root feed of Ca @ double the recommended rate (assuming this is a product with around 3%-6% Ca), and use the Mg as either a foliar or a root feed starting at a rate of about 1/4tsp (1g) per gallon of water.

You're gonna be chasing your tail on the Ca-, but you should be able to stop it from progressing to the point of impacting yield.

Yeah it's only showing up on a few leaves on the top...so far. Thank you for your quick reply. So you do recommend foliar feeding during flowering? I've always kinda been against it, just don't like spraying water (or anything wet) on buds. But you know what you're doing.... I only 'kind of' know what I'm doing ; ) I just so happen to get a gift card to a local hydro shop from my sister for Christmas, so I'll go scoop up a calcium only product today with it. Any suggestions on that? And also... when you add epsom salts to the nute/water mix...should I just toss it in and mix thoroughly? Or dissolve in a little warmer water then add & stir? I've always kind of wondered about that. Greatly appreciate your help SM. Happy New Year -danked

 

[Seamaiden]

I've never seen a problem caused by giving foliars, including just spraying with water. You don't want to go to town and really douse the buds, all you need to do is get some Ca all up into the stoma while they're open to stop the progression, you're never going to correct. If you divide up Ca from Mg in your feedings then you can give higher amounts of both Ca and Mg (don't need very much with Mg at all!), ya dig?

If the plant's healthy, you're not going to cause problems by giving a few foliars over the next couple of weeks. If it's already struggling...? They don't look anywhere nearly that bad, though. The problem, like I said, is that with Ca being immobile if you wait til you see problems, you've waited too late and thus, an Ouroboros is created.

I love BioLink 6% Ca, and miss it. It can be given via foliar or root drench. I now have Calcium-25 and having to wait to foliar is a pain in my ass. I hear Calplex is being discontinued, so right now just keep your eyes peeled, and look for 3% Ca, as close to 0% NPK as possible (some Ca products are derived from CaNO3, and that does provide a little nitrogen).

 

[Danked]

Gracias Seamaiden

 

[PotDragon]

It is tough to expect plants to perform well if you do not provide the proper environment.

75 f at 40% (!!!!!!) is not that. Get the rh in control before you start spraying/adding more crap.

Good luck. Stay safe. Get up and move faster.:D

 

[PButter]

I see I'm late getting in but I couldn't agree with Seamaiden more- re: Ca.

I foliar the girls everyday of their lives (for the most part). Its more about what you are putting on them(nothing too harsh or strong) and when.

 

[Seamaiden]

It is tough to expect plants to perform well if you do not provide the proper environment.

75 f at 40% (!!!!!!) is not that. Get the rh in control before you start spraying/adding more crap.

Good luck. Stay safe. Get up and move faster.:D

Uh... what's wrong with that low RH, besides being on the low side, and can you explain how that might affect calcium utilization and uptake?

 

[Tnelz]

I think ur environment is cool bro. Listen to the maiden!

Gracias Seamaiden

 

[Herb Forester]

Ca defficiency is often related to high VPD (low humidity). Transpiration gets too high and turgor pressure drops, limiting Ca transport. This is especially true at leaf edges, meristem, and calyx tips. Feeding Ca to the rhizosphere won't help, and even foliar spraying is of little use without correcting the underlying problem first.

 

[PotDragon]

Since you asked....

Low RH causes transpiration to occurr too quickly. This increase in evaporation leaves behind salts/ferts that would evaporate as well given time. This presents itself in yellowing, drooping, and in severe cases rust spots & necrosis. All of these APPEAR as similar to conditions caused by the nute schedule, but of course the cause is environmental.

Which brings us to 2014. The only "Deficiency Chart" is a mirror. On this planet, mmj has been studied in LABORATORIES by SCIENTISTS to come up with the correct additives & ratios. If your results are poor, you are doing a poor job. Period.

There is no cal def....ever. Use correct medium, correct nute schedule, in CORRECT ENVIROMENT. Or mix up some bull piss & Epsom salt cause you saw a picture of a yellow leaf and just know better.

 

[Cort]

SeaMaiden is usually spot on her advice. Go with it. Them plants are hungry.

While it would not hurt to bump your RH, I doubt a slightly lower than perfect RH is your problem.

 

[thunderfudge]

I think you are all correct.does anyone associate iron in on Cal mag problems?

 

[Seamaiden]

I never have, but my source water is high in Fe. But, given a set of nutrient samples that were sent to me and what one of them is (CaFeMg), you've piqued my interest, mostly with the why of you asking the question.

 

[thunderfudge]

I never have, but my source water is high in Fe. But, given a set of nutrient samples that were sent to me and what one of them is (CaFeMg), you've piqued my interest, mostly with the why of you asking the question.

I have no iron in my water, all metals are stripped at the water co by a resin substance which is then filtered by a bag of salt.no cations.i have a ppm of 120, pure salt.with iron being the beacon that alerts plants there is precious metals to uptake, I could pour damn near a whole bottle of Cal mag without iron with no fix ie; leaf distortion in new growth, fishooking at the ends of the leaves, twisting.they wouldn't uptake the Cal mag, because there was no iron to say,"drink up"lol.i ro now To Remove the salts.i Replace Membranes like crazy, run 1 1/2 t of Cal mag , up to 2 sometimes until week 5 and slowly taper down to nothing by 7 weeks.it is a constant battle.

 

[thunderfudge]

And Cal mag problems with h and g, especially with coco, typical

 

[Seamaiden]

I have no iron in my water, all metals are stripped at the water co by a resin substance which is then filtered by a bag of salt.no cations.i have a ppm of 120, pure salt.with iron being the beacon that alerts plants there is precious metals to uptake, I could pour damn near a whole bottle of Cal mag without iron with no fix ie; leaf distortion in new growth, fishooking at the ends of the leaves, twisting.they wouldn't uptake the Cal mag, because there was no iron to say,"drink up"lol.i ro now To Remove the salts.i Replace Membranes like crazy, run 1 1/2 t of Cal mag , up to 2 sometimes until week 5 and slowly taper down to nothing by 7 weeks.it is a constant battle.

Well you just taught me something new and huge (for me). Thank you.