I thought this was canoeing leaves

[lampost]

Ok there's another post right here about canoeing leaves, but I didn't want to jack someone's thread. Besides, these leaves look different.

Anyway, here is a picture. There's only one plant that is doing this out of a few.. I think a second one may've shown signs of it. It's not on all of the leaves but on several.

Anyway, what in general are the causes of this? I thought my temps were ok, but I think it may be heat or light because it happened to the plant directly under the lamp (1000W HPS). But the light was never closer than 18" I don't think...

lampost Reviewed by lampost on 02-19-2010. I thought this was canoeing leaves Ok there's another post right here about canoeing leaves, but I didn't want to jack someone's thread. Besides, these leaves look different. Anyway, here is a picture. There's only one plant that is doing this out of a few.. I think a second one may've shown signs of it. It's not on all of the leaves but on several. Anyway, what in general are the causes of this? I thought my temps were ok, but I think it may be heat or light because it happened to the plant directly under the lamp Rating: 5

[WashougalWonder]

Ya, that plant is stressing. It is transpiring as much as it possibly can and that is why they canoe.

Either too much heat, too much water, not enough air flow.

[lampost]

Thanks again! You're helping my ass out today!

I think it must be airflow (maybe combined with slight overwatering). Got ventilation turned off basically while the No Pest Strip is doing it's thing. Good news is that today is the last day of the NPS and it comes out tomorrow AM!! Also, plants were recently transplanted and are taking awhile to dry out in their new, larger containers.

[lampost]

Man, I gotta get this figured out as it doesn't appear to be getting better on it's own :jointsmile:

I'm certain it's not too much heat. I'm pretty sure it's not lack of air flow too as adjacent larger plants are showing no sign of this. There's a possibility that it's too much water, but based on how these symptoms presented themselves I don't think that it is... It appears to be getting worse still as it dries out. I tend to water on the light side I guess.

Could this be related to a Cal/Mag problem? I'm also seeing the rust/brown spots that are signs of Cal/Mag problems. I think my pH dipped pretty low (runoff at 5.3 - 5.5) for awhile...

This is happening to 2 plants. I guess I'm going to flush 1 and see what happens even though the soil is still pretty moist.

[PhatJay]

I had exactly this problem with my plants a couple of weeks ago. The "lipped" leaves that were affected were all in the top 1/3rd of the plant and the worst affected leaves showed the rusting/brown areas you also mention.

I overhauled my DIY ventilation system and it pretty much stopped the problem in its tracks. Some of the leaves that were not too badly affected went back to normal. But the more heavily affected ones kept the lip around the edge.

There are some pics of the problem in my grow log.

[PhatJay]

I just saw your other thread about this problem and you mentioned that you are using Tap Water (wish you had put all the information in the same thread as I now have more information to add).

I got this problem when I ran out of PH tested pre-mixed food/water and had to feed my ladies straight tap water for 4 days. I thought the "lipped" leaves and brown spots were related to the same problem, but after reading your post I now think the problems are caused by seperate issues.

I went back to my normal feeding schedule and overhauled my ventilation system at the same time. This worked for me.

[lampost]

Thanks for the feedback. I initially thought it might be related to air flow because I've basically shut down ventilation for a week while I have a No Pest Strip installed - today is the last day. I don't think air flow was the problem though as the other plants all look OK and don't show any sign of this. Who knows though... they are getting very little ventilation this week.

They did have very low runoff pH... maybe 5.3 - 5.5, so that leads me to believe it's either pH-related or related to a heavy-dose of nutrients. I heard Headband strain is very nute-sensitive and that is the plant that is doing it. However, I may wait until tomorrow to flush because I'll be able to get a good dose of air going through and I can see if that helps at all?

This is the first problem that has really got me stumped! I'm sure there's more to come

[PhatJay]

"I don't think air flow was the problem though as the other plants all look OK and don't show any sign of this."

"that leads me to believe it's either pH-related or related to a heavy-dose of nutrients."

I have 2 plants and one was heavily affected and the other one hardly affected at all.

Hmmm... approx a week after I had this problem. My plants started to lose their odour. So I switched from feeding 2 days on 1 day off, to feeding every other day. This didn't seem to have any affect on the leaf problems but my ladies started to stink within 2 days of me decreasing the feeding. So you may be right in thinking that decreasing food might help. I have no way of checking my PH atm so I can't give any insight on that front.

I am really glad I spotted your threads on this, this has given me more of an insight into what caused this problem. :thumbsup: If it eases your mind any, I had this issue during flowering and it doesn't seem to have affected my girls too much. The buds are getting fat and they sparkle like a mirror ball.

[lampost]

OK, well I was able to investigate this some more...

I decided to flush as I thought it might be more of a pH problem or over-nute problem. I had just fed them their first moderate dose of nutes a few days before. So I started flushing with distilled water (pH 8.0) and the runoff came out at 5.0! I think that's pretty damn low for soil and I have no idea how it got that low (other than the fact that FFOF soil is inconsistent shit). Anyway, this leads me to believe that pH and associated lockouts was definitely the problem. So I flushed with 1x the volume of the soil container and pH only came up to 5.4!! Looks like I'm going to have to flush again soon... I ran out of light time.

So, how can pH get that low! This plant is only 5 weeks old and was just transplanted 1 week ago from a 1-2 gal to a 5 gal! So there's fresh soil and I'd even added a bit of dolomite lime (very small amt though). The nutes I use hardly lower pH and I pH it to no lower than 6.8.

I just hope I can fix it before it hermies!

Lastly, I posted pictures of the symptoms again just to help anyone in the future that may have this problem. The leaves are canoeing, or curling up along the serrated edges. Also, I'm getting brown/rust colored spots on the leaves... as the soil dried it out they seemed to get worse and turn into patches in some areas. I'm not sure if this was pH lockout or nute-burn.

[redtails]

Looks like pH problems that happened to me, I never got it fixed for that plant so sorry I can't offer any advice.