• LED Grow Light for cannabis, HLG lighting, Percys Grow Room Ad
  • Ali Bongo, Head Shop UK, buy best bong UK, Percys Grow Room
Whats up folks! Jus...
Clear all

Questions Whats up folks! Just wondering anybody know what the general causes of leaf hooking downward?

3 Posts
3 Users
Topic starter
20220812 200757
20220812 200812

This 1 plant has always been a very dark green colour but had zero signs of nitrogen toxicity, no shiny leaves & no curl... until now!

It's in week 2 of flower and all of a sudden shows these hooked leaves!

I may have over did the ppfd but have lowered it to see if the new growth is better which so far it is altho now the new leaves are starting to point towards the light so am worried the same might happen to them...


Trying to figure out leaf language and I know its not simple but I'll try explain...

I Maybe over fed her but she's been needing water everyday even tho I'm in 7 gall fabric pots but I've only been giving her ~700ml a day with recommended dosage or less, of bio-bloom & top max and she may have gotten heat stress aswel as the possible light stress?πŸ€·β€β™‚οΈπŸ€”

Any ideas or advice would be great, cheers!✌

3 Answers

A little more information would help. What media is she growing in, soil or coco? If it’s soil what kind? What are the lights on and lights off temperatures and humidity levels. You mentioned ppfd, do you know the current level? Exactly what are you feeding her, how much and how often? What is the ph of the feed input? Are nutrients in the water every watering? Anything else you can think of adding, more info equals better information.

It looks like nitrogen claws but could be environmental. With this additional information we should be able to diagnose her.

Random acts of kindness make the world a better place


Β I would say it looks over fed and over watered. The light maybe an issues so check the manufactures recommendations and go with that. Light stress can also darken plants leaves.Β  Kind of a Reset. Do you have one of those cheap moisture meters? They aren't that accurate but for moisture they work pretty good. I did the same thing, I was watering mine on a time schedule and not when they were dry, I would feel them and they felt dry, enough. lol But the meter settled it. Once again it just a bench mark to go by, it's not gospel. I'm in 5gal/19L buckets and your in a 7 bag, mine was drinking 1 gal +, a day but not now and that daily watering was short lived. Another thing is if they are wet all the time, it affects how they take up nutrients and can cause a toxicity. The dark color shows she's full and on the verge of toxicity, so water with less nutrients and watch the color to lighten. It's good that she's that dark going into flower she'll use it, just light up on the food, the water and the light, (that's all LOL) but you already said all this up above. You've got this, it's hard not to get rammy with them, lol, I know. lol πŸ‘Β 

Topic starter


Cheers lads!

It's mad, I was gonna leave a day off watering yesterday but she was gettin droopy so had to give her a small bit of water only & she was grand again!


The clawing happened a few days ago but it's on all the new growth from top to bottom at that time so struggle to see it as light stress but then again... I've heard contradicting things about how leaves behave with light/heat stress also, but I'm sure it's very nuanced and case dependent aswel!πŸ˜…πŸ€¦β€β™‚οΈ


20220812 223317

Not much sign of nute burn... literally just the very tips the past few weeks!

Sorta tried to hold back since but them the claw came!πŸ€¦β€β™‚οΈπŸ€·β€β™‚οΈ

She's in soil, just a couple of john innes vegetable soils & top soils mixed together with some perlite!

The "runt" pheno of the same litter beside her has been lighter green the whole time and a lot less issues (but I'm thinking maybe because she was slightly further from the light!πŸ€·β€β™‚οΈ)

20220812 223343

I could try more water less often maybe!

she is a big girl, 10 tops, just over 2 feet tall & 2 feet wide!

20220812 223351


I think with the high temps / ppfd lately she's been flyin through the water and maybe suffered for a couple days but hoping its sorted now!

I moved the light closer with less intensity so temps are a few Β° lower!

I haven't checked pH of water, it's just tap that's let sit for 2+ days but haven't seen any problems as yet but no idea on ppm or anything yet either.

I did get a cheap hygrometer / temp & humidity has been between 30 & 60 throughout the veg /flower cycle mostly mid 30%s to lower 40%s during day but spikes at night.

Have a decent light recommended & bought from Shane at migro, the gls grow 300!

I had the girls on 400-500 ppfd during veg n tried bumping up toward 8-900 recently just before the issues showed but no tacoing or anything so am mad confused!πŸ˜…πŸ€£πŸ™ˆ

Have em back down toward 6-700 now and they're still praying upward... not sure if theyre good or want more or less but I know flat is the goal!

They leaves have been flat and straight most the time until I possibly over watered/fed & possibly fried em a tad!

Still flying in growth tho am amazed!... this light is doing better than the sun ever has for me here in Ireland!

Quicker flower development, tighter node spacing etc.


Our forum is free to join. We are an international cannabis forum that helps people all over the world grow their own personal supply of cannabis. Through our site you will find cannabis breeding forumscannabis deficiency forumsindoor cannabis growing forums, and much more. 

We are a home growers cannabis forum, and we only allow people who grow cannabis for personal use to be members. Our mission is to help you grow your own cannabis. We do not buy/sell/trade cannabis, or equipment for growing cannabis. Our site is strictly a cannabis smokers forumcannabis growers forum and forum for medical cannabis users.

Use our guides on how to grow cannabiscannabis grow diaries, and growers forum to find all the info you need to learn how to grow your own cannabis.

Any member who is suspected of growing cannabis for commercial gains will be banned immediately.

Please read our forum rules, and enjoy the site.

Find us on all social networks! Just search for Percys Grow Room