Cal/Mag during flowering

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Jan 31, 2011
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Hi everyone.. Do you guys use cal/mag with every watering or every week when flowering your MJ ? I am trying to find a reason why I am loosing so many lower leaves in flower and I think part of it is due to under watering but also possibly not using cal/mag consistently. I have used it -but only a few times.. Thanks Hero
4+ foot plants grown under CFLs would be my first guess. A cal/mag deficiency will show as crispy spots on your leaves, and they don't always fall off.

edit- And I use cal/mag with every feeding during flowering, which is every other watering.
So Doc bowles.. You think its due to not enough lumans reaching lower areas of the plants?
hero4u2b said:
So Doc bowles.. You think its due to not enough lumans reaching lower areas of the plants?

You mentioned in another thread that your lower leaves aren't dieing off first, they just fall off. I've never really run CFL's, but my guess would be the plants are shedding leaves to concentrate their energy on areas that are receiving light.
I would have to agree some that the light issue could be the cause. It really depends on how many lumens yu are putting on them and the size of yer grow area. If yu have enough light but are in a larger room that allows the light to dispurse then yu are loosing anywhere from 1/4 to 1/2 of yer lumens.:eek: I have reflective walls around mine to bounce every lumen back to the plants that I can get.:cool: (flat white walls in 2 of my rooms, and mylar on walls and ceiling of my other room)...I use cal/mag with every feeding from beginning to end. I even use a diluted solution of cal/mag and thrive alive in a sprayer to foliar feed my cuttings while they are rooting and they do fantastic:) I wonder if yu have yer area to low RH with fans blowing directly on the plants. That can cause them windburn and over drying for sure. Grow mojo to yer girls:fly:
I dont know but I sure would like to know. lol It might be a combination of several things.. There is good bud development from half way up the plant to the top cola.. its just the middle and lower leaves.. I am going to start using cal/mag every feeding.. and ofcourse water more..o and to Doc.. no.. they are deing first although not all are changing colors first. some seem to still be green but dry and some have turned a lil color. Thanks everyone.. Hero
With CFLs, even if you have adequate lumens, they simply do not penetrate very far. There is no doubt that the bottom part of your plant is not getting enough light. Whether or not this is your problem remains to be seen. Are the leaves yellowing before they fall off? What are you feeding them? Could it be a N problem?

I feed my gals Cal-Mag all the way through flowering.
With CFLs, even if you have adequate lumens, they simply do not penetrate very far.


I had a chart that showed the distance the light will go and what lumes at that range...but for the life of me I cant find it...But I know the CFL started looseing Lumes at 1.5 feet and drooped faster than any other
can ya add some lower light?

take care and be safe:bolt::bong:
I have 42 watters all around the plants.. from the middle down thou they lack light.. Most of the buds . forming colas are all above where they are.. Hempgodess.. I am and have been wondering if its a N def as well.. I am only using big bloom which has 0.01-0.3-0.7 fomular which I dont know why it is so low ( says liquid plant food FF) and Tiger bloom which says extra strength fertilizer rated at 2-8-4 and I used the cal/mag a few times but not every time I feed..Should I go try a small dose of grow big possibly? I dont know.. PS not totally yellowing but somewhat.. some are completly green but dry. Thanks
Doesn't sound like a Nitrogen def to me. Nitrogen deficiencies manifest as yellowing.
I have been adding calmag every other watering. I feed then the next water then feed so on so forth. Seems to working great.
BBFan said:
Doesn't sound like a Nitrogen def to me. Nitrogen deficiencies manifest as yellowing.

Yeah, that was one of my questions--whether the leaves were yellowing first. However, I would think that the nutes contain enough N that this is not the problem.
Well I do not know if it is even going to matter all the growth is in the bud. hairs. cola forming areas.. all the leaves that have fallen off were older shade leaves.. I guess I will be more concious of using cal/mag and watering more often.. Thanks everyone for the input. Hero
It's definitely a learning experience. My partner is 52 and has been growing MJ all his life, and he is blown away by how much he realizes that he doesn't know. I am the reader of the "grow team". I have several books, and constantly read and talk here, and I still haven't learned as much as I would like to know. They will probably finish just fine, and yu can apply what yu learn to the next grow. I personally feel that's half the fun of growing for myself.
Yup They need watering every other day now. I used cal/mag and the first full does 3 tbls of Tiger bloom.. ( usually use 1 or 2 tbls) even thou on the directions it says 2 to 3. There are alot of bud sites. colas forming everywhere.. I will keep you guys up dated as they progress.. Next grow thou I def am not going to let them get so big. lol Thanks Hero

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