Hey all my fellow coco growers I have a bit of a concern with my recent grow and hope to get some wisdom from the great people at GS. First some info about my grow: I'm using 60% coco 40% perlite. Started in solo cups then transplanted into their final 3 gal pots that I added about 50 extra holes for better drainage in. Strains are Super Lemon Skunk, Bubba Kush, Critical and Doctor from Attitude. The Doctor is the only strain not showing this problem. I'm using the GMB Advanced Nutrients Lucas formula with a bit of Cutting Edge Solutions Mag Amped and Cal Plant Amp here and there. I water them once a day a few hours after lights on using the drain to waste method with half strength nutes (around 600-800 PPM) PHed at 5.8-6.0. They are in week 2 of flowering and are about 4 feet tall. It started as a little leaf curl at the start of flowering (was perfect till the 12/12 flip) then has progressed to cupping and curling. Every leaf on all plants are healthy and dark green (but not nitro tox black green) and are overall flourishing except for the leaf cupping and curling. I have ruled out everything pretty much...temperatures do get a bit high during the hot summer days (89 max) and never below 70 during lights off. Drainage is more than perfect but this seems to be all the signs of over watering? I made sure I let my roots fill the pots before feeding once a day so it's not a underdeveloped roots problem or a root bound problem as 3 gallon pots should be plenty to support 4-5 footers in coco right? I will post pics later today or tonight but for now I just want to hear your comments on this. Thanks in advance! Optimo
Ya know, there're many things that can cause the crow toe leaves, but from my past experience there is 3 which is most common.. Over watering (as you said) High humidity Overdose or a buildup of nitrates... The other problem I see a lot is cold air (like from an A/C) blowing on a part of a plant... I would suspect this more if the crow foot leaves were just on one side of the plant, but if the whole plant shows signs of this all the way around, and usually starts on the outside older leaves first, but if it's all the way around, I'd be looking for one of the 3 above.... Like I'm running a 10'x3' SCRoG and my A/C blows down the backside of the scrog, well because this is where all the air flow is, humidity being drawn into the dehumidifier, cold air from the A/C, them back leaves will crow foot on me, but the scrog itself is fine.. That's my spin on the crow foot leaves anyway....
Sound like your lights are too close but not close enough to actually burn leaves. How about the tips of the leaves...any of them dry and light? Also nutrient burn looks like that for a bit. By cupping I assume you mean curling up and not down. When over watered leaves curl down and get fat looking. Under water or too hot they curl up and look thin. Could not hurt to flush without fertilizer but pH'd and move the lights away a few inches and see what happens in the coming week.
I think heat would be a curl "up" (the plant trying to not expose as much leaf surface area to the sun).... The OP's leaves are curling down or under....
Heat would curl up. Over water would curl down. The OP mentioned "cupping"which sounds like up-curl. Although he did suggest it looked like over watering.... Maybe some pictures would help...
You could be right , I read that and my mind went right to curling down..... So ya, my bad..... lol Thanks for pointing that out, I think I need a little more
Thanks for the quick replies everybody. Yeah, I ment they are cupping down like being over watered, not up. I should have been a bit more clear...the curling is not on every leaf, there are a few leaves that have no curl or cupping at all. The most effected leaves are the new growth around the buds and the old large fan leaves. Do ya'll think feeding 800 PPM one day then 400 PPM the next (I water untill about 20% runoff) and repeating this every day through the whole grow could cause overnute? I have only flushed once and that was when I started seeing sings of the eagle claw and dark leaves. Since the flush all new leaves are the perfect shade of green and everything looked fine for a while then I started seeing tons of leaves start cupping down which lead me to believe it was overwatering but I can't see that possible with such a high perlite to coco ratio. I was also thinking it's a possible salt buildup/over nute problem but had a hard time believing it due to the low PPM I feed them. When I did flush I did it for 3 days with a very weak nute solution and tested the runoff several times and the PPMs was the same as what I flushed with every time.
Hmm... sounds like they are kinda drowning which is hard to fathom with coco and so much perlite. Here's something maybe... try putting a spacer under each pot lifting them to make draining more complete. I then use a baster to suction the overfill. Otherwise, the roots may be sitting in a pool of water constantly. Your root system sounds very well established and perhaps exceeding the pot size. The spacers make it so that the overfill totally clears the pot, that way flushing is more complete and over watering less likely. Best wishes!
Nah Man, I think you had it right. It was in his thread title "cupping under". I missed that. Cheers!
Could be transplant shock..one of my stains always shows drooping after I transplant in to 12/12..a bit a supertrive cures them up in a week..cant overfeed in a coco perlite mix, unless you feeding constantly..which I dont think you are...800ppm is good too. My 3 and 5 gal all take over 1000ppm on .7 scale Sent from my SGH-T889 using Grasscity Forum mobile app
Sorry for not replying for so long...I can't use a PC as much as I would like to. I want to let everybody know the outcome incase others have the same problem or just want to hear a really nice feeding system....hopefully this will help out. I've come to the conclusion that it was a bit of salt build up causing a mild nitrogen toxicity. A good flush and plain water feedings for 3 days then slowly adding nutes at really low PPMs has cleared up all the problems. All new growth is fine and the buds are exploding. So if you're like me and based your grow on things you have read about, being bad to flush coco, don't believe it! As long as you reintroduce nutes back slowly within 2-3 days you won't see any deficiencies. I've adapted to a new water/feeding system now and it's working wonders. I first water them with plain water (no nutes) until I get a bit of runoff then right after the plain water feed, I water them with the desired full strength nute solution until I see a bit more runoff which will happen really quick with a lot less nute solution because the coco is already saturated from the plain water. So doing it this way ensures there will be no salt buildup and it will save you a lot of nutes since you don't have to water so much using the drain to waste method. I've tried DWC, soil, supersoil, promix and straight coco. I'm blown away by the performance of a 60/40 coco/perlite mix. Never have I seen my plants grow so fast and look so healthy, never have I seen buds swell up so fast and look so frosty so early into the flowering stage. Coco/perlite is by far the ultimate medium in my honest opinion and I will never use anything else ever again. Thank you all for the help and taking the time to read my posts. I wish you all well and have a dank day! Optimo
I have the same problem. The leaf edges roll under, almost creating a tube, and the whole 5 fingers curl under. It looks like an eagles claw. The leaves are deep green, with no burning at all. I'm growing just the one plant in perlite, with a 50 litre storage tank. The timer waters for five minutes every 4 hours. I have grown this way for 15 years without a problem until now. The problem started when I changed to flowering nutrient and 11 hours lighting three weeks ago. The lower leaves are large and flat, no problem. I have searched the net and the only cause which seems to apply is a build-up of salts, as suggested here. I am emptying the tank as I write and will try using plain water for a few days. Thanks for the tip. I'll let you know what happens.
I had just a couple fan leaves crow on me. Everything I read pointed to too much N, but I haven't even used any nutes yet. After reading this it makes perfect sense. My intake is being drawn from an a/c vent which was hitting the side of my plant. So that's why the tips were curling down and looking kinda purple. Gonna adjust that intake and see what happens.Thank a lot dude!
Well I've had a little more experience in this issue, in my personal opinion, it's a combination of lower light levels, nutrient rich, and cooler than average day temps, like when you have an a/c blowing on them...... This past grow I had an arm grow past the light, everything was fine until it passed thehood, then within days started to see the crow foot. What I believe is happening, with the lower light, the plant can't process the nutrients normally, so they build up in them leaves..... And we all know light, temperature, humidity, and nutrients all play off each other..... Like I push 75w per sq ft, someone running say 30w per, well they're not going to be able to run the nutrient levels I run without buildup rather quickly. Peace....