Leaf edge curling why???

So when a plant curls it leaf margins or edges we all assume humidity and temps, but what happens when its not this?

I see lots of peoples plants curling the leaf edges like humidity problems. Why would a plant try to roll it leaf margins and increase its surface area and open the stomata on the underside of the leaf as much as possible when humidity levels are perfect?

Could it be the plant is trying to transpire as much as possible, trying to pull too many ferts and water through its xylem and phloem systems, expelling as much into the air through transpiration as possible to alleviate some imbalance, possibly to do with too many nutrients being made available.

Either way i see with humidity problems or just naturally curling the leaves due to somthing else kind of dictates the plant is working harder than it should be.

Dose someone wana nail down leaf edge curling when it is not caused by humidity, i have heard all kinds of reasons ranging from the down right stupid such as genetics and strain related to most any other reason people can think about, i feel it is a nutrient imbalance or overfertilization problem but if i knew that i would not be posting this. Peace

ive nute burned with no curling upward its usually a downward curl and only at the tip. and usually you see some sort of yellow discoloration for a nute burn. Whats the temp at? hydro or soil? nute line?

ghantron said:

ive nute burned with no curling upward its usually a downward curl and only at the tip. and usually you see some sort of yellow discoloration for a nute burn. Whats the temp at? hydro or soil? nute line?

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Good point but maybe its an imbalance of nutes or too much nitrogen or somthing, temps and humidity are always perfect, i see it now and again, especially younger plants but it seems to mystify most growers who dont have temp or humidity problems in soil, just wanted to know if anyone wanted to nail it down, the plant is obviously saying somthing by rolling its margins, i feel it dose this to be able to transpir more as if it were a humidity problem. Peace

if it's curling upwards like a canoe then it's respiring trying to keep cool, if its curling down like an inverted taco, that's a sign of too much nitrogen.

Pureblood89 said:

if it's curling upwards like a canoe then it's respiring trying to keep cool, if its curling down like an inverted taco, that's a sign of too much nitrogen.

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Definatly curling up like a conoe, not my problem but i just was curious and wanted to get it nailed down so we can pass on the info.

It transpires to keep itself cool but the temps and humidity are perfect, what is the leafs problem now? Peace

something i can think of if it is hydro is that maybe the roots arent getting enough water, so its curling to preserve. I donno... give more specifications on ur grow to help

ghantron said:

something i can think of if it is hydro is that maybe the roots arent getting enough water, so its curling to preserve. I donno... give more specifications on ur grow to help

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Another good idea, if the roots had too many ferts that would inhibit the intake of water.

So you think the plant would be trying to conserve water when the leaf edge rolls.

Its not to do with my grow, the fact that i post in the problem section is merely because this is the best place to for it.

You have had a couple of good ideas, i need to do some googeling first and get back with some ideas based on what you have said. Just want to get things sorted so that other growers and me know what it means. Peace

when they curl like that its becouse of the heat, or you have it too close to the lamps.

1. Guard cells close the stoma in darkness, so much more water vapour is lost in the light (during the day)
2. For water to evaporate from the leaf, heat is required. Therefore the higher the temperature, the higher the rate of transpiration.
3. In a dry environment, more water vapour is lost. When the air around the plant is humid, the concentration gradient is not as steep, so less water diffuses from the leaf.
4. Due to the fact that air saturated with water vapour often form near the stomata, wind also plays a role in transpiration. When the wind blows across the surface of a leaf, the saturated air is pulled from the leaf.

Can be due to too much wind movement or light intensity

I looked into this for a long time dude but could only find enviromental causes like heat, wind and humidity to be the only causes. It has been reported for some deficiencies but very rare.

I must conclude that it is only down to or most likely going to be heat light or humidity, too much light possibly but i think the leaf would just fry at that point. I really wanted to try and link it to somthing other than these environmental factors but alas i could not. Personally too much wind will cause other problems wether local or generalised through out the grow tent although the wind may drop the humidity somewhat maybe so indirectly could be a cause.

Seriously gave this a lot of effort only to see that it is always gona be the environmental factor that causes leaf edge curl. At some later point in my growing life i may find out i was wrong about this but for now the chances of it being somthing else are very slim so i will not concern myself about it.

If your leaf edges curl raise the lights, lower the temps or check the humidity (and grow room fans, i take it the oscilating option on the fan control will dramatically reduce this problem). Sometimes the leafs get too hot even though you think they arent. A 24 hour light period may also amplify existing leaf curl because the duration of heat etc etc is longer.

Hope this helps anyone who comes across this thread in the future. Peace

ghantron said:

Can be due to too much wind movement or light intensity

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I have really problem in same way
plz read my forums and check pics for that
waiting for your opinion
best wishes

pic please

heres a pic.

(Mn) manganese deficiency; leaves canoe a lot, and they will close completely...

the only way i know how to fix it is by folair feeding. have you been feeding with cal/mag or something with (Mg)Magnesium, too much magnesium will block out (Mn) manganese.

when did this start, did you happen to change your nutes recently.

dirtysnowball said:

(Mn) manganese deficiency; leaves canoe a lot, and they will close completely...

the only way i know how to fix it is by folair feeding. have you been feeding with cal/mag or something with (Mg)Magnesium, too much magnesium will block out (Mn) manganese.

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if that was for me. its not my current grow, but yes i do folair feed with a product that is a nitrigon product. its called magic green.
i thaught it was from light being too far away, but i never really found out why it did that. it was like a year ago.
but this is a great thread and im ready to learn.

yes a mongo frog that was for you. i want to see kingsgrow1 pic though...

Haha, i am not posting pics!lol! It was just a discussion thread unfortunatly.

I havent got round to Manganese but feel that would be a hard deficiency to pick up but as you say cal/mag might aggrevate manganese. I do feel that if you added too much cal/mag you would lock a lot more than just manganes out but until i look into manganes in greater length i hesitate to comment. I am up to Sulphur at the mo, done NPK, cal and mag, sulphur was an easy one and really not common.

I feel that any additive or supplement containing seaweed would prevent manganese deficiency but a lock out would be more common or generally the problem. I never really see any micronutrient def till late flowering then they show quite a bit, boron can be a common one etc etc.

Yer sorry dirtysnowball but im just going back through all the nutrients and certain problems like leaf curl.

Do you think manganese deficiency would produce leaf margin curl? I know it can be responsible for canoeing but leaf edge curling is my target here???

So i learnt all this stuff a long time ago but just want to go through it again to refresh my memory and learn a few new things. I find it is not nessecarially a lack of any particular nutrient but an imbalance that causes greater problems in my grow. Again sorry, some of my plants may exhibit problems but i dont really discuss them in threads moreover discuss the whole subject of certain nutrients and environmental factors. I dont like magic bullets or simple answers, all nutrients are inter-related so learn them all is my principle. Micro nutrient def seem very rare to me though, last on my list.

So in conclusion snowball and anyone else i have come to the hypothesis that leaf edge curling is almost 100percent heat/humidity/too much wind. Any comments for or against are welcome but pics of my plants are very rare at the moment due to me dealing with a lot of whorlled phyllotaxy and breeding depression, i only do pics when i have no problems!lol! Breeding depression can bring on nute def, toxicity and all other problems very quick due to weak plants so until i start a new batch of fresh F1 generation seeds and dump these inbreed and selfed S5 and S6 generation seeds i will always have too many problems to completely solve. My yeild is still good though. Peace and comments welcome.

a mongo frog said:

View attachment 1772341heres a pic.

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Even if it was manganes deficiency, which seems quite rare to pick up imo, i would not look for the fix but more look for the cause. Yer you could add some manganes supplement but really should you have to with decent ferts? is this just a lock out or toxicity? I see the leaf edge curl and canoeing but also them leaves under neath dont look affected only the uppermost leaves, probably possible that the tops of the plants are suffering from high temps, humidity or some other environmental factor.

Leaf edge curl seems as if the plant is trying to hold back water and conserve it, too much heat or too low humidity will cause excess amounts of water to be lost from the leaf surface hence why it curls and shuts the stomata imo.

I have no easy fix unfortunatly but find the reason you got the problem i.e. ferts lacking certain nutes or incorrect supplements for growth or lights simply hung too low and you will find the cure.

Please learn away dude but when you are knowledgeble then dont forget to share the info about, especially with me!lol! Peace and good luck, no answers are simple in life.