Leaf Edges turned upwards, heat stress indicated but temps are good.

[daihashi]

-indoor or outdoor
Indoor

-soil, soilless, or hydroponic
Soil

-Soil type/brand
50/50 mix of Promix and Fox Farms Ocean Forest

-Anything you have added to the soil
Perlite, about 20% mixed in.

-Soil pH
Between 6.3 and 6.8

-Water source
Just tap water.

-Water pH
PH of water alone before adjustment is 7.3
-Age of plant
6-7 weeks old on average.

-Type of fertilizer
Age old Bloom and Hydroplex Boom Booster by botanicare.

-Rate of application
Once a week

-Lighting source and distance from plant
400 Watt HPS, 18 inches away from majority of the canopy. 10 inches away from the highest stray side shoot.

-Temperature (both day and night if you are running a dark period)
Temp at 18 inches away is 75.6F degrees.
Temp at 10 inches away is 82F degrees
Temperature at night is about 68 degrees at it's lowest.

-% Relative humidity
Currently at 38-40% RH.

-Lighting schedule
12 on / 12 off. Lights go on at 6am and go off at 6pm, which is about the same for natural lighting right now where I'm located.

-Type of ventilation your room has[/B]
1 20" Lasko Box fan for intake. A 8-9" circulating fan inside the cabinet and another 20" Lasko Box fan for the exhaust.

The lasko fans supposedly push 3000 cfm at their highest setting.

daihashi Reviewed by daihashi on 03-01-2008. Leaf Edges turned upwards, heat stress indicated but temps are good. -indoor or outdoor Indoor -soil, soilless, or hydroponic Soil -Soil type/brand 50/50 mix of Promix and Fox Farms Ocean Forest -Anything you have added to the soil Rating: 5

[SFGurrilla]

Pics?

[daihashi]

Now for the problem.

The edges of some of my leaves seem to be indicating that they are having heat stress.

What is confusing is that the temps in my grow cabinet are good as listed above.

I raised the lights an inch and then I took the plants in the 3 gallon pots off their stands (stack of dvd's) to move it even further away from the light until it was 18 inches away.

I then rotated my crop to ensure they weren't all in the same spot and getting hot spots.

Even with my hand placed over a particular leaf that's curling badly I feel no discomfort at all. So I'm not sure that it's a hot spot.

I've started leaving my cabinet door cracked open slightly just incase hot air wasn't escaping fast enough (I doubt air flow is my problem here given my fan setup.)

beyond that my plants look healthy. Here are some pics of the actual problem.

This picture is of the plant that is furthest from the light. It just moved to this position last night. Previously it was right beneath the hps light.

[daihashi]

Pics?

yeah I had seperated my plant problem post from the troubleshooting form to make it easier to read. Must've caught me in between postings.. heh.

[SFGurrilla]

I always seem to do that, I don't really see a problem with your babies man, they look good. Some strains do weird things, its all about the genetics. Just keep feeding them neuts and keep the pH around 6.2 - 6.8 so the neuts dont lock up, also a balanced pH could be your problem for stress on the leaves. I doubt its the heat.

+Feed neuts every other watering, not only once a week.

+Make sure you wait atleast 15 to 20 minutes before you know for sure what your new pH is once you balance the water!

I'm cutting my crop in about 20 minutes.

Check the link in my sig.

:rastasmoke:

[daihashi]

I always seem to do that, I don't really see a problem with your babies man, they look good. Some strains do weird things, its all about the genetics. Just keep feeding them neuts and keep the pH around 6.2 - 6.8 so the neuts dont lock up, also a balanced pH could be your problem for stress on the leaves. I doubt its the heat.


I'm cutting my crop in about 20 minutes.

nice, be sure to post pics.

As for it being the strain. It hasn't done this the entire grow. Weird that it's just starting to do this after 1 week under HPS.

It was previously under CFL's. The growth of the plant exploded under hps and then about 2 days ago or so I saw the edges of the leaves curling upwards and can't seem to figure out the cause now.

[SFGurrilla]

Only thing I can think of is.

+Neuts lock up
+unBalanced pH stressing your leaves

Don't use tap water!!!! Go out to the store and buy some distilled water. Or try Zypherhills. Watering could be your major problem I missed that your using tap water.

[daihashi]

Only thing I can think of is.

+Neuts lock up
+unBalanced pH stressing your leaves

Don't use tap water!!!! Go out to the store and buy some distilled water. Or try Zypherhills. Watering could be your major problem I missed that your using tap water.

I'll go fill up some jugs today with distilled. Would it be a good idea to go ahead and run a flush?

[SFGurrilla]

Flush it, tap water has to many impurities, I grew all organic even up to the bug spray and neuts.

Good luck with it man keep in touch. Check my sig.

[daihashi]

well I started flushing my plants. I didn't get the initial run off PH but after a gallon and a half of distilled water my ph was 5.9. After 3 gallons of water it 6.4-6.5.

Seems like the PH just kind of crept up on me suddenly.

I'll be drilling holes in the sides of my pot (1 hole each side) to help aerate faster and recover from the flush. I will do one more mini flush later this week (1 gallon or so).

Hopefully this is my problem. I really wasn't expecting the PH to be so low especially considering I just transplanted.

Is this caused by the salt build up I've read about? (haven't read alot on it, just as I'm reading daily threads and come across it)

btw, great looking grow SFgorilla. Can't wait to see what your dry yield weight is.