N toxicity close to flower

Hi gang. First post here and I have to say this forum has been a wealth of info for me. Thanks for being here!

A bit of info first.

4x4 grow tent
250w MH supplemented with 4 T5's running horizontally around the tent. (yes, I know the hood is under powered but I'm upgrading to 600w hood, hopefully within a week, right at flowering time)
Growing 12 GDPs (I know it's a bit crowded but cant bring myself to cull any of my babies... yet. I'll bite the bullet and probably pull 3 out and turn them into moms soon. Light penetration is still pretty good since I have the side t5's going.)
Media is a mix of Fox Farms (FF) Ocean Forrest (OF) (had 30-40% perlite mixed in) and ReadyGro Aeration, 2.5g pots.
Nutes are FF Big Bloom (BB) and Grow Big (no tiger bloom yet of course)
Using PH'd RO water.
Runoff PH testing in 6.3 - 6.8 range.
24/0 lighting schedule
Temps running between 76 - 79 on average, RH averaging around 40-45.
Supercropped only the top. Nice even canopy.

Edited: Just adding that this is my first grow.

I had an issue where my girls showed signs of N toxicity (dark green leaves, new growth was a bit twisty, stems were a bit weak, a bit of clawing here n there.). My mistake was giving them grow big too soon since growing in FF OF I flushed with 2-3x pot size with RO water. This was a week ago and they seem to be recovering extremely well but I'm right at the 4 week veg mark. Cell structure has recovered so the stems are where they need to be strength wise. Leaves are still too dark and honestly I'm not sure if they will lighten back up again. Anyone? They have gotten a bit lighter but I'm not sure if them lightening back up will be a good indicator of them using the extra N that was there.

Since the plants cut their N uptake in early flowering my plan is to let them veg for 1-2 more weeks to allow them to use the stored N before switching to flower, feeding only water or at most give them half dose of BB 1x/week. I'm thinking 1 more week only. What do you guys think?

A bit of a followup question since I'm changing my hood from the 250w to 600w... I know I should switch ASAP, but my funds are tight. Would I cut my yield even more by waiting to upgrade til 2 weeks into flower or should I be eating Ramen noodles and upgrade right at flower?

I appreciate any input gang. And yes, I know I'm going to have people hopping up and down telling me I have too many plants in there lol. Feel free to give me suggestions on maximizing total yield by cutting down to x number of plants (assuming 600w AND the 54w T5's supplementing. I'm loving the side penetration from the T5's.

Thanks in advance. Here's a couple of pix.

I think your plants look nice and you should chill out, but that's just me!

i dont see the tips burnt or clawling

hexthat said:

i dont see the tips burnt or clawling

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I should have been more clear that the pics were a little over a week after flushing. Luckily the tips didn't burn but there was some clawing of fan leaves (maybe 5 or 6 leaves per plant). There are a few that are still clawed tho. The stems were weak, which I found just how weak they were when I supercropped a couple. They just flopped on me fairly easily. Stems are MUCH stronger now after the flush and a week of time went by. The primary indications were the extremely dark leaves which showed up much better out of the tent lights, twisty new growth, and weak stems. I think I caught it fairly early.

I did have some of this on 2 plants on lower/older growth tho but have not had it grow on the same plant or spread to anywhere else.

Holylander said:

I think your plants look nice and you should chill out, but that's just me!

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Lol yeah I'm being a bit of a nervous nellie Pretty much just wanting to confirm that I should extend flowering by a week or 2 to allow them to run thru the stored up extra N.

And thanks for the complement on how they look. Cant wait to enjoy the fruits of my labor.

Watered last night and found a few of these. There are other leaves with burnt tips but all minor. No major damage. I'll keep an eye to make sure it doesnt continue but I'm hoping this is mostly the after affects of overfeeding since I flushed the heck out of them already.

Are your lower leaves going I to the solution while watering?? That's a possibility..

Yes, there are times when the lower leaves will get into the solution when I water, but it's not the case here. These leaves are on the lower-mid section of the plant and these developed during the time I've only been watering with straight RO, no nutes. Thanks tho. The worst is in the pics I posted but there's burnt tips on some of the lower most leaves, old growth. I'm sure all is fine, was following up to hexthat's comment about no burnt tips since I found some when watering yesterday. I'm in the being patient, watch n wait mode right now. Tough since this is my first grow so of course I'm being hyper vigilant.

Hey, my 1st grow too and my tips are a lot more burned and I have major heat stress every day, but the plants are hardy. Unless you see something really spreading, especially on more than a few leaves and doubly especially on more than one plant try to be patient and don't do too much. That's what I have learned so far, that messing around too much causes more trouble than good. Pls don't misunderstand, if there is a problem it's awesome if you tackle it. But a leaf here and there on a single plant, it's normal and it won't make any difference. If something starts spreading then clearly as someone who is vigilant to your credit you will be on it.

Thanks Holylander.

If I wasnt so vigilant I wouldnt have caught the N toxicity so soon, before it could do some real damage. I've learned from this minor mishap and looking back there were a couple of warning signs I could have acted on sooner, including not feeding them the grow big until later in the process when using FF OF (which I saw mentioned numerous times but didnt heed the advice).

I think I pull off the whole nervous nelly balanced with patience and understanding that they are plants and not perfect thing fairly well. Especially when us new growers are hyper-excited and want to dote on our plants, checking every little spot etc as we try to learn and dial in the environment we provide. I hope I didnt come off as freaking out or anything. Was really just looking to confirm my suspicions, the remedy, and checking my plan to let them veg another week with the pros here. They really are doing extremely well.

Looking forward to picking up my new hood and 600w ballast next week then it's flower time!