Very unhappy ladies - Ca def?

[Sloth]

I've got 3 girls here on day 59 with what I believe to be calcium deficiency. Some info:

Temps: 23-26c
Humidity: 45-55%
Lighting: HLG QB260 running at 50%
Light distance: 24"
Medium: Plant Magic Soil
Soil PH: 6.5-7 according to my very cheap soil meter. Runoff comes out at 6.5 regardless of input PH.
Veg Nutrients: Plant Magic OT Grow, Biosilica, Evolution + Shogun Calmag (as foliar spray and drench), Molasses, Ecothrive Microbial Tea
Flower Nutrients (after stretch): Plant Magic OT Bloom, OT Mag, OT PK (1-2 weeks after stretch stops), Molasses, Ecothrive Microbial Tea
Watering practice: Watering very slowly (with gaps over an hour or so) until runoff. During veg there was a good wet dry cycle of 3-4 days but now they're drinking more slowly and I'm not letting them dry out quite so much. I believe not allowing pots to get as dry to be correct practice during flower once roots have developed?

I've basically been chasing calcium and magnesium deficiencies on these plants since mid veg. I've given calmag foliar feeds 2-3 times a week until the end of stretch, have added it to feeds as well as adding 1g mag per 10l on every watering. In the last week the Blue Dream and Cream Cookies deficiencies have gone really bad and I'm losing a handful of leaves per day. Transpiration has gradually slowed on all plants compared to veg, despite the humidity being lower.

I've fed only 0.5ml bloom every water up until this deficiency were "the hydro guy" recommended upping their feed. I upped the bloom to 1.5ml but they are just getting worse. I've read that plants can be hungry for cal during week 3-5 flower but this is crazy. I feel like there should be enough available but thet can't access it for whatever reason. I flushed Cream Cookies out of desperation and it did sweet bugger all to help. The Sour Stomper I feel can make it to harvest but I'm concerned for the other two.

I have turned the light down to 50% (130w) in the hope that it will ease the stress on the plants because it appears to be a dangerously powerful light able to burn plants from 30".

Fast Buds Blue Dream

Fast Buds Cream Cookies

Mephisto Sour Stomper

This is pretty gutting as this was easily my most successful beginning to a run ever with my plants actually filling the tent for the first time. I would really appreciate any advice anyone can offer.

Sloth

 

[Waira]

Sloth, I see no info about pH management,... on nutes going in, in-pot measurements (you'll need the right tool for that of course)... Dosage info, a TDS or EC measurement would help understand the conc. of what's going in there,...
This is a multiple-mess here mate, hard to say what's what this advanced, but I see P, Mn, Ca issues,... defc.'s mostly, but between the pH unknowns (a likely cuase) and the possible over-dosing of Ca-Mg which can sort-of lock out each other and other nutes (like P and Mn) as a form of toxicity, it's a guess as to which, or both, it could be,... Flushing will purge excess nutes, but also magnify defc. one (that are not pH or toxicity locked out), and it's wise to measure both pH and ppm/EC of run-off as you go to see how much is loaded in there, and how well it's working on removal,...

 

[nbbeerguy]

Seems like an awful lot of stuff in your feeding regime keep it simple and you will have less problems

 

[Sloth]

Thanks for the replies guys, I agree I should keep it simple - especially as I'm yet to have a successful flowering stage (apart from my first ever run, where it was simple...). These plants were beautiful, easily the biggest and healthiest plants I've grown yet, but once the stretch had finished it went downhill so fast.

For veg I fed root stimulant starting 1ml up to 4ml every feed. Silicon 3 times @ 0.25 - 0.5ml until flowering began (I Ph'd down to 7 before adding other nutes). 0.5ml calmag almost every feed. Grow at 0.5 - 1ml roughly every other feed until end of stretch. I started feeding magnesium at the end of veg @ the recommended 0.1g per litre and have fed on nearly every watering since.

Once stretching stopped I fed bloom nutes starting at 0.5ml, then 1ml, then 1.5ml. Alongside these 3 feeds has been molasses, mag, and calmag @ 0.5ml per litre for the first 2 feeds. That brings us up to this point. I've gone from removing handfuls of leaves per day during veg to watching them fall off by themselves as soon as the buds set!! The calmag foliars have been with RO water @ 10-15ml per litre, 2 - 3 times per week.

I was PHing to around 6.5 with phosphoric acid to help the calmag uptake but stopped 1-2 weeks ago as I read that it can damage the microbial life in the soil. Unfortunately, I can't afford a decent soil meter currently and on testing runoff the other day it read as 6.5 regardless of the ph of the water that was going in.

So I am basically looking at flushing the medium and then feeding a full dose of bloom nutes - does this sound sensible? Should I PH the water that I flush with? It's around ph 7.5.

 

[Waira]

...well, cumulative inputs can start to cause toxicity, pH and other forms of lock-out,.. with base nutes (which have Ca and Mg), molasses, Mg (?- as a epsoms?), and Ca-Mg, you may have overdone the Ca/Mg inputs.. molasses is a significant source of them as is,... this might be what caused this to happen, but it's had to say now,....
when making you nute solution, always start with Ca-Mg first, then add in other stuff, let it sit for a few minutes, and then test for pH and adjust if needed,.. remember, pH adjusters also add in ppm's, so your final solutions may have been a bit rich too contributing to the overall overloading in the soil,.. pH in-pot, for what that meter is worth, isn't showing to be off, but run-off can be deceiving for actual in-pot pH, not reliable,.. but at least with that reading, it wasn't way off which would indicate at least there's a problem there,...
pH adjusters don't harm the soil life per se, the high ppm load in the soil is the problem, for both them and the roots (osmotic imbalance)...that, and really off pH solutions!
... I think much of the symptoms on top are B defc, pretty rare, hard to ID sometimes,.. but too much Ca can cause a uptake issue with B....
A flush is probably a good idea, 2-3x pot volume,....use the RO water plus a little tap to get some ppm's/buffering capacity in there,... she'll finish face-first, but she should make it,...
Speed drainage by placing the pots on newspaper and a paper towel on top, make sure it gets good contact with the base drainage holes; this will start a wicking action that will draw excess water out faster, so less soggy-time for the already PO'ed roots!

 

[Sloth]

Hey man, thanks again for your response. I have flushed The blue dream she was at 1000 ppm, her symptoms look to have stopped progressing, which is great. Also, Cream Cookies leaves have stopped falling off and she's starting to put on size after a week of no bud development. I think overdoing the calmag sounds about right - a fast bud rep advised me to start feeding at day 10 because my Pineapple Express had terrible cal Def at that point already. The Pineapple Express is at day 59 and is yet to flower - I'm thinking of transplanting and then initiating flower in a couple of weeks once the tent has more space, do you reckon that's wise? Hopefully it can bump my overall yield up! Also thanks for the drainage solution - you had mentioned newspaper to me in a previous conversation and it inspired me. What I do now is put a folded quick-dry sports towel under the pot after watering, when it is soaked through I wring it out, replace and repeat until the pot is no longer soaking at the bottom. It works fab! Thanks for all your advice, it really is appreciated. I feel very fortunate to have help available when doing this, it can feel a bit overwhelming trying to figure it out alone.

 

[Waira]

Cheers Sloth, you're welcome,.... all in a good day's work! :smoking:... wicking is a niffty trick, ay? Anything to take some beating off the roots,.. over about 20 min. of suffocating saturation, the root start to starve out for O2 and die.....
...Do what you can with the PE mate, I have a non-auto'ing plant now too- ...sooo, outside she goes with the rest of the photo's!

 

[Sloth]

Ah mate, I'm jealous! I'm thinking of starting a little auto outdoors this week as a fun project. The PE is waaay to big to be out in my garden though. .. a good problem to have I guess but still....damn UK laws

 

[Jackson]

I had the same problems and my leaves looked just like yours almost like a blowtorch hit them. @Waira told me check ph and that was it!

Even after using ph perfect nutes I always checked ph.

Jackson

 

[Capt.Quirk]

...well, cumulative inputs can start to cause toxicity, pH and other forms of lock-out,.. with base nutes (which have Ca and Mg), molasses, Mg (?- as a epsoms?), and Ca-Mg, you may have overdone the Ca/Mg inputs.. molasses is a significant source of them as is,... this might be what caused this to happen, but it's had to say now,....
when making you nute solution, always start with Ca-Mg first, then add in other stuff, let it sit for a few minutes, and then test for pH and adjust if needed,.. remember, pH adjusters also add in ppm's, so your final solutions may have been a bit rich too contributing to the overall overloading in the soil,.. pH in-pot, for what that meter is worth, isn't showing to be off, but run-off can be deceiving for actual in-pot pH, not reliable,.. but at least with that reading, it wasn't way off which would indicate at least there's a problem there,...
pH adjusters don't harm the soil life per se, the high ppm load in the soil is the problem, for both them and the roots (osmotic imbalance)...that, and really off pH solutions!
... I think much of the symptoms on top are B defc, pretty rare, hard to ID sometimes,.. but too much Ca can cause a uptake issue with B....
A flush is probably a good idea, 2-3x pot volume,....use the RO water plus a little tap to get some ppm's/buffering capacity in there,... she'll finish face-first, but she should make it,...
Speed drainage by placing the pots on newspaper and a paper towel on top, make sure it gets good contact with the base drainage holes; this will start a wicking action that will draw excess water out faster, so less soggy-time for the already PO'ed roots!

Thank you for for your tips on possible remedies. I used your flushing technique for pre-harvest with great success. Replaced paper towel with a bath towel. Now the ball and chain is PO'ed.