Help. CAL/MAG Def? Canoe leaves using Lucas, 3 weeks into flower

Need help asap.

They were all healthy yesterday. I watered today (1 day late watering (some plants were dried out) and noticed alot of plants with these...

I have about 5 plants with these severe def.s. maybe cal? The leaves affected are very brittle with a couple of leaves already falling off. Some affected leaves are curling up (maybe cause of heat?). A couple more beginning to show alittle bit of rusting (tiny dots) and last but not least 3 or so plants with an upside down canoe leaf. Other than that everything else is healthy Pics below. I have 1 headband growing there as well, it is perfectly healthy so far.


Strain: Purple Kush
TIME: 3 Weeks @ Flower
MEDIUM: PROMIX BX (SOIL LESS)(Nothing has been added, I noticed major problems with dolomite lime if I add it, so I decided not to use it and they were actually fine until now)
NUTE: Im using Lucas formula 0-8-16 @ feed + water + water, repeat. (2 days apart).
WATER: 10ppm R/O @ 6.4 pH (Alot of guys use this pH and have no probs (Norther Farmer, etc...)
TEMPS/HUM: Daytime 76-85 F - Night 66-77 F / 40-55% HUMIDITY

Stadium grow, turning plants 45 Degrees every day.

Should I spray a foliar 1 TBS dolomite lime into 1 gal r/o water affected leaves? Will the affected leaves turn back to green? or die off. Or do I have to buy cal-mag.




Leaves Upsidedown canoe pic





Upsidedown canoe




Beginning stage




Defeciency Pic





Closeup Defeciency

I think you need to drop your ph to 5.8-6.2 and feed more often, once a week in a soiless mix is not enough food, Id go 3-4 times with food then one off to flush a little. Whats the ingredients in promix?

GET MO said:

I think you need to drop your ph to 5.8-6.2 and feed more often, once a week in a soiless mix is not enough food, Id go 3-4 times with food then one off to flush a little. Whats the ingredients in promix?

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Promix has Peat moss, vermiculite, perlite, dolomite lime,

yep, none of that stuff has nutrients so u definitly need ta feed more. That doesnt look like cal-mag problems to me, mine usually get yellow round the edges with calmag problems.

Ok new updated pics...

Yesterday I sprayed the leaves with 1 tbps of dolomite lime to 1 gal r/o water.

That is why there are "white" powder mildew looking spots on the leaves, so ignore that. The leaves are still exactly the same as they were yesterday. I did happen to take pics of the "worst" looking plant in the bunch. Ive been scowering through the infirmary and ive seen alot of pics with almost the same probs as mine but it appears to have no real answers.




Top of the plant (Ignore the white spots, its just the foliar spray) A bit of red stems, some canoeing





This is the start of the progression. The small speckled rust spots, then it spreads.





Mid/Late progression. Abit of curled up leaves as well.





Ignore that white spot on the leave in the background, its the foliar spray. Closer up on the plant. There does seem a lack of nutes on the bottom of the plant as well. I noticed this plant drinks very very fast. I need to start watering everyday with this guy now.




The end... This leaf withered and dried to the bone. It is finished. The plant right next to it is fine though....


Should I increase the nutes to feeding it full str every other watering?

I'm gonna go with phosphorus def.

Lucas has plenty of P but P is only taken up at pH's above 6.4 and even though you pH your water @ 6.4 your promix BX is really starting out at a pH 5.2 "outta the bag" and your RO water and nutes are doing nothing to raise this pH much.

I bet if you measured your run-off or even a 1 part soil to 2 parts distilled water slurry you'd find your pH is prolly around 5.8-5.9, which isn't bad, but can cause P def.

The red petioles and curling of the leaves leads me more to P def then Ca, although many growers find they need to add calmag to their lucas when using RO.

I think you are just using the wrong amounts of dolomite that's why you find you have problems with it.

Next time add 1 tsp/gal of soil and it should settle more at a pH 6.3-6.5. If you add 1 TBS/gal it would prolly settle more at pH 6.9-7.0 and this would be bad.

solid advice from blue dot.

Blue Dot said:

I'm gonna go with phosphorus def.

Lucas has plenty of P but P is only taken up at pH's above 6.4 and even though you pH your water @ 6.4 your promix BX is really starting out at a pH 5.2 "outta the bag" and your RO water and nutes are doing nothing to raise this pH much.

I bet if you measured your run-off or even a 1 part soil to 2 parts distilled water slurry you'd find your pH is prolly around 5.8-5.9, which isn't bad, but can cause P def.

The red petioles and curling of the leaves leads me more to P def then Ca, although many growers find they need to add calmag to their lucas when using RO.

I think you are just using the wrong amounts of dolomite that's why you find you have problems with it.

Next time add 1 tsp/gal of soil and it should settle more at a pH 6.3-6.5. If you add 1 TBS/gal it would prolly settle more at pH 6.9-7.0 and this would be bad.

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Thanks. Yeah when I was using the mix, my promix + dolomite mix runoff was coming out around 6.5-6.9 and it was driving me nuts. They stunted the growth and my leaves were around 1 in large. I transplanted clones into just promix and they were normal/huge and not yellow! so I knew i was doing something wrong with the promix+lime mix so I just avoided it all together.

Promix is such a headache... Is there anyway to fix this right now? Maybe watering at 6.9 pH? I forgot to mention that when I R/O the water it comes out around 6.4-6 naturally.
So when I add nutes it goes all the way down to the 4's and then I add around 1ml of pH up to get around 6.4 again and I use that. When I just water, I just water it plain since its around 6.4


could somebody else chime in on this? Some of the defs seem consistent with MG def. since I have some leaves that are curling upwards, and alot of affected leaves are twisted and crispy brown, yellowing in older leaves, etc...
Only one or two stems are alittle purple, but no purple can be seen on the leaf veins/stems (Underside)(its all white there). I also have no red/purp/blue tint on the leaves. And the pictures of P def doesnt look much like mine at all ? The MG def pics in the stickies look kinda like mine

Leaf curling up can be a sign of a Magnesium (Mg) deficiency caused by too low of a pH level. Magnesium deficiency will show as a yellowing (which may turn brown and crispy) and interveinal (in between the veins) yellowing beginning in the older leaves. Interveinal chlorosis (yellowing) will start at the leaf tip and progressing inward between the veins. It could also be a sign of excess heat and humidity in the grow room.

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I've been useing pro-mix for years. When i have problems , I flush . Looks like over fert to me. Again flush.

Your plants are both over fed and over watered...... why do you need to water so often?
There is no way that plant is Defienciet with P with how close the dosages are given....

not to mention those leaves are fried, when you got a P issue that is actually caused by low levels of P the leaves DO NOT curl, they stay normal and just have huge spots.

Now nute burn will cause brown leaves, but also will make them curl upwards; those plants are clearly suffering from high levels of nutes. So a flush is much in need and water less and choose a different feeding regimen other than lucas formula.

Here is the problem with lucas formula, it only works with some strains of cannabis, NOT all. Some can grow awesome with it and some can't get past certain stages unless they were removed from using lucas formula.

Some people live by it, but they should also take note not all strains work with it.

Remove your plants from the mixture, or if you don't..... you need to get them off the number of times your feeding them. Also your night time temps are cold enough to slow the plants metabolism down which it won't eat as much so your putting food in there when there is already enough and it's just building up. Temps 70F and under can trigger it.

First get the amount of food it's getting first, fix that and find out what the pH will be then, cause high nutes will cause pH to go out of wack.

Your plants roots are also staying too wet, curling leaves under like that is a sign of moisture stress, another thing causing the issue, roots stay wet too long will not absorb nutes so the concentration of nutes in the soil is raised by that as well.

I honestly don't think promix is good, it's not bad; but you have to know how to use it though.
Depending on which mixture you are using, if I remember correctly some have lime already in them? Or no? will have to double check...

and I would get your plants off lucas formula and feed them what THEY want.....

go by the size of the plant when you feed......
I don't hate lucas formula, don't get me wrong; but most problems I have seen over years is not all strains like it.

I have seen huge plants grown by this formula, so it works; but the combination of things can make it not work; it also has to be the grower too.

So to sum it up, you must not water them as often stop feeding lucas, choose different feeding based on what the plant needs not based on a formula then after flushing check the pH 2 days after flush then if correct range you can start feeding every 4-7 days and dosage goes by the size of your plants.... how big is your plants and how big is that bag they are in?

MynameStitch said:

I have seen huge plants grown by this formula, so it works; but the combination of things can make it not work; it also has to be the grower too.

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You have a lifetime of experience in dirt that I don't but I'll say there's nothing wrong with the formula and different plant strains. The issue is with individual growers and soil mediums that are not completely devoid of nutes.

Beyond that, the 'Formula' needs to only be adjusted in strength if the light intensity is not high enough. Lucas does recommend 0-5-10 for low light flowering.

I've experienced nearly everything there is with Lucas as far as basic hydro and soil goes. When you understand and properly apply it, it works every time on every strain.

Keep up the good work Stitch, you're definitely one of the best plant troubleshooters out there.

hey hydro-soil! i'm growing grand daddy purps and was thinking about using floranova and was wondering if you've tried it or know anyone that has tried it? what were the results? also i'm doing hydro in 5 gal dwc and i got that canoe leaves going to and my humidity is around 62-68% so is that my problem? thanks guys!

Hey there hydro, Ya, I agree with you; thats why I said it does not work with everything cause there is too many things that could go wrong and mostly growers error does count a lot too.

Trying to use lucas formula in void soil and it won't work like it would.

Lucas formula was originally made for hydro at first if I remember right' it's been a while so I will have to double check...... later people tried it in soil and worked too.

Thanks for the kind comments hydro ! Really appreciate it!

bron2k said:

hey hydro-soil! i'm growing grand daddy purps and was thinking about using floranova and was wondering if you've tried it or know anyone that has tried it? what were the results? also i'm doing hydro in 5 gal dwc and i got that canoe leaves going to and my humidity is around 62-68% so is that my problem? thanks guys!

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Too many variables to tell Bron2k. Post a thread in the infirmary with the details and it'll be easier to get help.

Yes, I highly recommend Floranova for hydro with RO water and a ppm of 1300-1400.

MynameStitch said:

Your plants are both over fed and over watered...... why do you need to water so often?
There is no way that plant is Defienciet with P with how close the dosages are given....

not to mention those leaves are fried, when you got a P issue that is actually caused by low levels of P the leaves DO NOT curl, they stay normal and just have huge spots.

Now nute burn will cause brown leaves, but also will make them curl upwards; those plants are clearly suffering from high levels of nutes. So a flush is much in need and water less and choose a different feeding regimen other than lucas formula.

Here is the problem with lucas formula, it only works with some strains of cannabis, NOT all. Some can grow awesome with it and some can't get past certain stages unless they were removed from using lucas formula.

Some people live by it, but they should also take note not all strains work with it.

Remove your plants from the mixture, or if you don't..... you need to get them off the number of times your feeding them. Also your night time temps are cold enough to slow the plants metabolism down which it won't eat as much so your putting food in there when there is already enough and it's just building up. Temps 70F and under can trigger it.

First get the amount of food it's getting first, fix that and find out what the pH will be then, cause high nutes will cause pH to go out of wack.

Your plants roots are also staying too wet, curling leaves under like that is a sign of moisture stress, another thing causing the issue, roots stay wet too long will not absorb nutes so the concentration of nutes in the soil is raised by that as well.

I honestly don't think promix is good, it's not bad; but you have to know how to use it though.
Depending on which mixture you are using, if I remember correctly some have lime already in them? Or no? will have to double check...

and I would get your plants off lucas formula and feed them what THEY want.....

go by the size of the plant when you feed......
I don't hate lucas formula, don't get me wrong; but most problems I have seen over years is not all strains like it.

I have seen huge plants grown by this formula, so it works; but the combination of things can make it not work; it also has to be the grower too.

So to sum it up, you must not water them as often stop feeding lucas, choose different feeding based on what the plant needs not based on a formula then after flushing check the pH 2 days after flush then if correct range you can start feeding every 4-7 days and dosage goes by the size of your plants.... how big is your plants and how big is that bag they are in?

Click to expand...

I watered them the other day with plain pHed 6.5... I checked today and they a tiny bit better... When I say better I mean they do not look worse, and the "spotting" has not progressed at all, so its all good.

I agree the lucas for promix has been a bit of a headache for me, but Im still learning and still have alot more to go.
I am thinking of changing the nutes. What do you recommend for promix? I was thinking of going organic, but Im up for anything that gives better yields.
I know NorthernFarmer uses peters bloom formula, used planks and watered about a liter per gallon bag to little or no runoff. full str every 3rd watering I believe and waters every 2 days, that thread is what I was inspired by so I went with that only with using lucas. The weird thing was, I expected it to work the same as him... So I copied his whole routine... I was doing great until the third week.

Thanks so much for the info. Im going to have to redo the whole stadium thing since I do not have anything to catch runoff, and I have to mop it up everytime (yes it sucks). I was thinking of just using black poly and stapling it and having it slope down into a bucket... much easier than to buy and build another 10 2x6's and making a V shape or whatever.

THe thing was I was not expecting a "overfed" thing cause I didnt see not one bit of nute burn. The only reason I was feeding that much and watering was because I was following a set schedule, trying to emulate another persons grow. I have 2 headbands in here as well and they are rocking... I mean not one single problem with the lucas and 2 day waterings... The PK on the other hands are a headache...

First get the amount of food it's getting first, fix that

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Can you explain to me on how to do that? You mean feed full str, then check PPM 2 days later and check the PPM of the runoff?

I checked my runoff on 3 of my worst looking plants and the WEIRD thing is that the PPM @ .7 is at:
Plant1: 510
Plant2: 1600
Plant3: 1040

thats a big difference... 510 vs 1600 and they both look just as bad as each other... Lucas formula @ full str is around 1300 I believe, pH runoff I believe was around 5.8 (6.5 going in) (gotta doublecheck)

So to sum it up, you must not water them as often stop feeding lucas, choose different feeding based on what the plant needs not based on a formula then after flushing check the pH 2 days after flush then if correct range you can start feeding every 4-7 days and dosage goes by the size of your plants....

Click to expand...

How would I go about doing this? Water plants, wait til its dry on soil 2in then water again. Third watering feed full str? Or maybe every fourth watering? or I have to check the PPM then feed? I have many plants and it would take forever to check runoff on every single plant. Everywhere Ive researched and read told me to do some kind of schedule, so I just tried to emulate it Im still new so I dont know much about reading plants. (Just the basics)

They were transplanted into 1 Gal bags and about 9in (Shortest) and (tallest) 19in . Average is around 1 ft. (3 weeks flower)(They went in about at 10-20 days veg).

Also what do you think the cause was for the canoe leaves?
So I should stop feeding at full str every 3rd watering or maybe space the watering apart to maybe every 3 days so Im feeding every 9 days? instead of 6
My mistake I believe was I was feeding full str @ one liter with no regard to plant size? Next time I feed Im going "picture the plant scrunched up into a container and feed the amount of nute water for that size" maybe about 3/4 liter and water about a liter per plant. (A liter for 1 gal bag in moist but not dried out soil will not have runoff)

drow said:

So I should stop feeding at full str every 3rd watering or maybe space the watering apart to maybe every 3 days so Im feeding every 9 days? instead of 6
My mistake I believe was I was feeding full str @ one liter with no regard to plant size?

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You did awesome to look for a relatively easy setup and emulate it. It's a natural mistake to not figure in environmental differences.

Since you have a lot of plants I would change a few things.

1# Switch to a lower feed strength about 1/3rd or maybe a bit lower to start with and use it every watering. This way you don't have to keep track of which plant gets fed when and can water them anytime they're dry.
That's approximately 2.5ml Micro and 5ml Bloom per gallon.
(Stitch? What would you recommend the pH of a diluted Lucas solution to be? I've always run full str for one or two feedings and then RO until they looked a bit hungry again. )

2# Let them dry out almost completely so they begin to droop. Lift or weigh the pot to get a feel for how heavy it is. Water it and then don't water it again until it's almost that same light-weight feeling as it was dry. This way you're not over watering and they get plenty of time to seek out the remaining moisture with new root growth.

when i started using flora nove my plants went crazy. but i kept using it and for some reason only those first 4 plants went apeshit. the rest looked better than i ever had them look before those 4, but i am still trying to replicate those 4. i really like it although i am using something else cause my store ran out of it when i needed it. i may just go back there now that they have some and start using it again. i am using parts 2 and 3 now instead of the one part. so far i am not too impressed.

i have the same thing going on with the reverse canoeing. i think also, according to what mynamestich said, that i have probably been overwatering. that is what i am going to do. use the l.t.p. method instead of watering every day or every other day. and see what happens.

I have one male Durban Poison that, in soil, really doesn't thrive unless the pH is upped to around 7 when I water it. Then it gets really green and lush.

In hydro it does perfect, just like the others. Go figure.

Blue Dot said:

......

Next time add 1 tsp/gal of soil and it should settle more at a pH 6.3-6.5. If you add 1 TBS/gal it would prolly settle more at pH 6.9-7.0 and this would be bad.

Click to expand...

Hello all,

Yeah, I have found that at 1 TBS per gallon nails the pH @ 7 for a long time.

I use about 1/2 tsp per gallon these days with excellent results with a re-used and ammended peat based soil (FFOF, Kelloggs Patio Plus, EWC, blood, bone, liquid kelp)


minds_I

i use lucas in soil. ive had to adjust the formula a little. theres too much N for my plants after the stretch. the canoeing leaves is a sign of too much N. the dry crispy leaves that spot and curl up is mag def. those spots are cal def.

the lucas formula is 0-8-16 in flower. i adjust it to 0-4-12 because of this theres less cal+mag so i amend the mix with epsom as needed.

see how green this plant is. this is like 6-7 weeks into flower from clone.