Cal/Mag battle white widow/sour diesel

Hey y’all. I seem to have a reoccurring cal mag problem. I’m starting to suspect I may have a nutrient lockout. What do you all recommend for ph testers? My autos are in week 2 of flower, and they seem to be flowering well. I just need them to hang on for another 3-4 weeks.

Is it common practice to flush them with a nutrient solution in this phase of their life cycle? I read it helps, in order to restore root zone ph and to wash away and salt build ups. Just don’t know if it will have a negative impact on yield at this point.

Thank you all.

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week 2 of flower is JUST THE BEGINNING…even for an auto. You will not hurt an auto using just water. Actually, we tend to decrease nutes for auto’s, more than or close to half of recomendations
cal/mag…should not give you nute lock…they are amendments, not nutrients
ph tester…unless you are coughing up a cpl hundred for something like a BLUELAB…just get test strips
I use 2 cheap ph meters (like 12 each amazon) and take an average but the strips are much more accurate and work well in SOIL TOO
what is the substrate you are growing in and what nutrients do you feed (AND WHEN)?

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Been using the technaflora bloom nutrients. Every other watering. I am in soil. Ocean forest.

SEE IF YOU CAN GET ANY PICS UP with what your concern is. Are you continuing with micro or JUST BLOOM?
Need to see t maybe diagnose a little better. When / where are you adding the cal/mag…straight or mixing? Do you check the ph if you mix?

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I can’t seem to upload any images as the files sizes are too big. Let me see if I can find a work around.

Also. This is my first grow. So I’ve only been following the instructions on the technaflora for the different stages. Nothing additional.

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Good start…Notice how yellow is on the outer edges? How are the lower leaves, same or is most of the yellowing up on the upper leaves? Try and get another shot further away…show more of the plant.
Cal/mag issues are usually affect older leaves and from the center OUT…not inward.
Nitrogen issues usually work their way UP the plant
Heat stress usually looks like what I see here
or PH issues…image starts like this

Are you using techniflora BLOOM ONLY? that and cal/mag? Bloom has hardly ANY Nitrogen. In early flower you still need some nitorgen…If the K or the P & K get too high, they will lock out ANY AVAILABLE Nitrogen…and Magnesium!!!
image Mag issue - looks very close too

So, to move further, lets see if we can zero in
How close are lights to issue? What are the temps? Rh?
DO you have a fan circulating the air? I see fan leaves covering the buds, do you defoliate…looks a little crowded but hard to tell from a closeup shot. Those buds need light…
lets go from here…can’t drink the ocean, right?

So I notice it mostly on new growth. There are older leaves that are way toward the bottom that have yellowed and dried up but nothing significant. Some of the older leaves are from when this happened before. And honestly I also feel it’s too crowded however was super hesitant to defoliate because I’ve read so much that says I shouldn’t with autos. The light at this point is about 8” from tops of plants and I can’t physically get it any higher. As for nutrients, it’s the “flowering stage” recipe from technaflora. So it includes, boost, bloom, blossom, thrive, mag/cal, etc. I run the exhaust fan and also have a little fan to circulate more air. Temp is typically about 24C and RH is usually right around 55%. It fluctuates a few degrees and percentages as the day flows.

So looks like the 8" distance to the light is the culprit. The bottom of the plant is becasue the tops are going to use the nutrition from the leaves for bud formation…a good thing

You can defoliate some of the underbrush. Never more than 20/30% per plant AT ONE TIME. I would do 1 plant and wait 3/4 days to see the rebound. If ok, do the others. You arer gonna get more stress from the light than you will from defoliating…I would only start with 1 plant becasue the stress will be compounded…light burn / defoliate.
The under side NEEDS TO BREATHE…
LST…we usually do not like to BEND plants, especially autos, this late in the game but if you secure the stem to one side (right, left, front, back), you can fishook the branch higher up and start pulling it over. Not all at once,a little each day. You do not want it to break / crack but you CAN lean them over little by little. After lights off, they usually are a little softer, hopefully, unless you got a lot of silica in there. Then the branches will be stiffer but TAKE YOUR TIME…THEY WILL BEND. You need another 4 to 8 inches.
I would not change a thing on the nutrition side…From a WHOLE, they look good
Lets ask the Doc to take apeek and seek his opinion
@MDBuds what do you think?

@RYANAZAUDIO @Mrb53004 with autos this always happens in flower before you start to get that fall fade. The lower leaves go first because they get no light and the energy is saved for the bud sites and leaves getting light. They fade bottom to top. No need to worry about it as it is natural during flower. Just pick the dead ones out that are brown and crispy. The golden yellow faded ones are still good as you want the whole plant to start getting that fade. It shows nitrogen is leaving the plant and the chlorophyll is beginning to break down. That’s what you want in mid to late flower. It lets the buds stack and get sticky and there’s less chlorophyll to cure out of the bud after harvest.


Would adjusting my light schedule help at all with this? I currently run 24/0 would knocking it back to 18/6 help mitigate the problem?

Thank you both for your input. I really do appreciate it. I’ll try to make some room today and see how she does. I’ll keep you posted or reach out if I have new questions.

Thanks again — hope you both have and awesome week.

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I used to run 24/0 but…might be my imagination, my plants do better with a little nap. I now run 20/4. Also, my dark time is daytime…My tent is outdoors, hottest part of the day is pm so I lights off at that time. I lights on at night and it helps keep them warm…

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Gotcha. My tent is in a room in my house so the temp stays pretty consistent. I’ll try to give them a 4 hour nap though and see if that helps along with the other techniques.

Thanks again!