Tops Turning Yellow Just a few days in to Flower.

Okay so quick question. I am on my second grow just a few days in to flower. The whole experience from building a room, to growing, and of coarse smoking my home grown has been great fun. Just the other day I sent my girls in to flower , and real quickly the tops where the flowers are going to grow started to turn yellowish. I transplanted a few days before the 36 hours dark period between veg and flower. And within a day the tops were turning yellow. I have watered twice since sending to flower but one was a feeding. I am using flora series from general hydroponics (micro, grow, bloom) in a simple 50 50 mix of coco fiber and fox farm ocean forest. Is this yellowing a concern? My plants have always seemed extremely healthy. I just started giving them the "transition to bloom" feed. I would add pics but the yellow is hard to see due to hps lighting.
So this wasn't all that quick of a question but any advice or opinions is greatly appreciated.
Thanks in advance.

P.S. If pics are necessary to determine the problem/ solution I will get them, just doing so is a pain in the ass from my phone and quality isn't great.

Do you think it could be to close to the light, kinda like a bleaching?

Good advice thanks for the reply. They are about 2 maybe 2 1/2 feet away from the lights. And my lights are air cooled... although I am still pretty new to growing from my (personal) experience I don't believe that is the problem. And since I grow in a tent I really don't have the option to raise the lights. Is it possible this is normal? Or should I be concerned about a possible nutrient deficiency?

MileHighLoyal said:

Thanks in advance.

P.S. If pics are necessary to determine the problem/ solution I will get them, just doing so is a pain in the ass from my phone and quality isn't great.

Click to expand...

W/O pics it's a pain in the ass to diagnose and the quality aint that great.

True that. I appreciate the advice. I just tried to get some pics but the gold light just camouflages the yellow. I'm using one 1000w hortilux and one 600w from some other brand I got at htgsupply (I know that's no help). Anyway if I take a pic right when the lights turn on before they turn gold it will come out clear. I will do so tomorrow.
Thanks again.

Seriously doubtful that light would bleach out a plant. I think it's probably Nitrogen def.

Okay. I am using 1/3rd of the suggested nutrient feed (according to Gen hydros flora series) and 50 50 mix fox farm ocean forest and coco fiber. And am in the "transition to bloom' phase. It seems like that should have enough nitrogen considering I very recently transplanted from 1.7 gal. Up to 5 gal. With fresh soil mix of coarse. And my most recent watering included nutes. Maybe to much bloom feed? The tips of my leaves are unaffected so I really don't think its nutrient burn. Anyway I'm gonna get some pics tomorrow so hopefully that will be helpful.
Thanks for the help.

Throw some blood meal in there as a top dressing and water it in. Do a few spoonfuls at the time.

What's your pH measure too

I veg under t5's and then switch to a 1000w HP's, and was having this problem every time I went into flower. Someone told me it was BC plants have pH swings when they start to fruit/flower, and that it causes lockout and resemble a deficiency.

But for me that wasn't the problem. I raised my light and it fixed it. I bought a ph meter and started using a more stable acid to lower pH with just to be on the safe side, but I'm pretty sure my 1000 w was just a little too close.

Are any of the leaves starting to taco or curl up?

I've never heard of a 36 hour dark time between veg and flower and wouldnt do that myself. Just flipping to 12/12 is fine.
To prevent yellowing too soon I continue to run light veg nutes for 2 weeks or so at this point before I change to bloom nutes and my plants stay nice and green longer.

I've heard of the 36hours regimen, I've also heard of folks who use a really ducked up schedule like 24 one day off the next... It's all bullshit and does nothing, plants in nature do not experience this so reacting positively to messing with their lights is highly unlikely.


what I do is run the veggie nutes on SEEDLINGS, even after putting them into 12/12, soon as I notice pre-flowers, into 12/12 they go. I feed them the transition to bloom formula until, sex is definitely determined, I then switch to full bloom.. By the time I'm done, I usually end up with 2 plants 4 foot tall in a 3 x 3 area, dropping 12-16zips in about 90 days, start to finish.

2x 400w mh/hps. For this flowering though, I went and picked up a 1000w, I wanted to see if I can increase the yield by getting more light to the bottom of the plants. Plus the 1000w I notice now there is very little shading.

my own variety that I've bred through the years.