Trouble in flower

[Piper]

Brothers Grimm – Grimm Glue

12/12 for 25 days

indoor – Sohum soil – 20 gallon grass roots fabric pot

4’x4’x8’ – Vipar Spectra KS5000 – 20 inches from top

77 degrees 53%RH – PH and EC unknown – lite fungus gnats

No water for over a week – no nutrients ever – just RO water

I have had 3 semi successful runs in 5 & 7 gallon pots. Watering a 20 gallon is a different animal. I think they are overwatered with light burn but not sure. I could really use some help.

[Piper]

[Piper]

[mrgrowit]

Well the plants look to be yellowing all over which makes me rule out light burn. The Sohum soil should get you through the entire grow without any additional feedings. How long did you Veg for? Maybe a long veg period and now in flower they are out of nutrients? Are you able to get a pH or EC/PPM measurement? I know it’s not routine to do those measurements when growing with organic inputs but that info can be helpful if there are problems.

Light distance, temp, and RH look fine. You mention no water in over a week; Are you keeping the medium moist at all times or doing drybacks between waterings?

[Piper]

Hi! Thanks you for the reply, I watch all your videos! Veg was a little over a month. This picture was taken August 28th. Flipped to flower September 26th.Got a little wild with the cover crop. I have a Blue Lab PH pen that is a year old but probably dried out 6 months ago. Should I try to rehydrate and calibrate? No EC pen. When it comes to watering I tried to keep them moist but not really sure what is happening. This is my first time with fabric pots and cover crops. The smaller plants are in better shape. Willing to try anything at this point. Have FF trio on hand, should I feed the larger plants?

[Piper]

Also half way through veg I moved two plants to a separate tent. They all have the same issues but the largest of the bunch is rough. 

[mrgrowit]

Beautiful picture with the cover crops! Yes you can try to rehydrate and calibrate the pH meter but there is a high likelihood that the probe is no longer good. Without the pH measurement, we don’t know if the medium is in the acceptable range for nutrient uptake. If the pH in the medium is too high or too low, you could get nutrient lockout and see deficiencies. Without the PPM measurement, we are also just guessing what the problem could be. It could be too low of PPM indicating it needs a feeding, or too high of PPM causing a nutrient lockout. So it’s really hard for me to suggest something for you at this point when we really haven’t figured out what is causing the problem. If I had to guess without pH or PPM measurements, I’d think it was a lack of nutrition in the medium since all plants are impacted and all are yellowing all over. I wish I could give you a better answer.

[Piper]

Thank you, seedling and veg was a lot of fun this run. I fed two of the plants full dose Fox Farm trio using week 8 from the feeding schedule. The color improved after four days. That points to nutrient issues but I’m worried they may have been under watered. I was watering 2 gallons every three days with a fan above and below the canopy. I stepped up the watering to two gallons every other day with no run off but not sure if that’s enough. Would under watering affect the nutrient uptake toward the sides of the fabric pot that was always dried out? Maybe the middle of the pot was depleted of nutrients from veg and the outer portion of the pot was to dry to contribute? I’m not sure how it works. My plan is continue feeding one tent and only water the other. I would like to amend the soil after this run with craft blend, worm castings and build a soil big 6 micro nutrients, will that be ok having used FF trio on 40 of 80 gallons of soil? I have to rewatch the video you made about amending soil. Thank you for helping me.

[Piper]

Going to feed all four plants, can’t watch them suffer.

[Piper]

Replaced the old RO with a six stage mid grow. Possible issue?

[CamZ]

100% could be an issue. Correct me if I’m wrong, but that puts minerals back in the water doesn’t it? That’s balanced for human nutrition, not plants. With plants, the more pure the water I the better. It’s like an empty train. Mineralized water already has passengers, thus it’s unable to pick up new ones.

[mrgrowit]

Your question: “Would under watering affect the nutrient uptake toward the sides of the fabric pot that was always dried out?”
Answer: Dried out soil could absolutely negatively impact nutrient uptake. When the soil is dry, microbes go dormant. When they are dormant, they aren’t actively breaking down organic matter converting it into a form that the plant can uptake.

Your question: “Maybe the middle of the pot was depleted of nutrients from veg and the outer portion of the pot was to dry to contribute?”
Answer: Interesting thought but it’s pretty much impossible to say for sure the middle of the pot was depleted vs the outer sides of the pot.

Your question: “Replaced the old RO with a six stage mid grow. Possible issue?”
Answer: I agree with what @CamZ says in the post above me. To add to that, if you add minerals back into the RO with that 6th stage filter, you may need to adjust the ratio/dosage of the other fertilizer you add in. For example, the 6th stage filter you have says it adds back in calcium, magnesium, and potassium ions. Therefore, you should be cautious when adding in additional inputs that have those elements in them since too much of one element can inhibit the uptake of other elements. Keep in mind that this is general guidance and I’m sure many people have the 6th stage RO and ignore what I just mentioned and their plants turn out fine lol. So I guess it comes down to how much you want to gamble haha… You mentioned on 10/26 you were going to feed; what fertilizer did you use?

[Piper]

Hey CamZ and MrGrowIt, thanks for the reply! I have an update. I was watering wrong, the fabric pots feels sorta doughy when they are moist at all times. I got a backpack sprayer and have been watering slow twice a day giving them a couple quarts each. What CamZ said about the 6th stage checks out, I ended up removing it and using 5 stages. When I fed them on 10/26 I used Fox Farm Trio, week 8 from the soil schedule, 1 gallon full dose each plant. Did the same feeding 11/2. Not sure if I should feed again. Today is day 48 since flip to flower. Breeder (Brothers Grimm) has flower time at 56-62 days. What’s your thoughts on amending the soil after using fox farms trio?

[CamZ]

They look great! I wouldn’t ammend anymore personally. I’m not sure if you mean amending for the next run or for the end of flower. Can you clarify?

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