HELP??

[THC7]

This is a first for me in the 4 years of growing. Some of my leaves started turning yellow and spotting in 3rd week of bloom and today the leaves on the tops of 70% of the plants started to curl up. The PH is 5.7-6.2 and PPM 1400-1600. Room temp 80-85 when lights on. Using GH products and have been doing the same feeding all along with no problems. So I flushed system and filled with fesh water and no nutes. Going to see for a few days if they recover. Any suggestions would greatly be appreciated.

[gainesvillegreen]

You need to fill out the troubleshooting form at the top of the Plant Problems forum here. It will tell us what type of system you have for some more help.

[THC7]

This is a first for me in the 4 years of growing. Some of my leaves started turning yellow and spotting in 3rd week of bloom and today the leaves on the tops of 70% of the plants started to curl up. The PH is 5.7-6.2 and PPM 1400-1600. Room temp 80-85 when lights on. Using GH products and have been doing the same feeding all along with no problems. So I flushed system and filled with fesh water and no nutes. My system is an aeroponic with 8 ft. trays with 2 sprayers on each hole. Going to see for a few days if they recover. Any suggestions would greatly be appreciated.

[THC7]

I moved thread to plant problems.

[Illusion]

fill this out to get maximum help:
http://boards.cannabis.com/plant-problems/127058-troubleshooting-form-yay-you-know-you-wanted-one.html

[hybridlove420]

youve got 2 identical threads in the problems forum now....

usually problems are ph or nutrient related.

for a hydro rig, your ph looks fine, maybe a smidge higher (6.8-5.3) will be usefull, but probably not your problem.

try reducing nutrient levels slightly as your first problem sounds similar to a burn

your leaves curling up is sometimes related to Mg deficiencies i believe (check first though), and may be corrected with a light epsom salts foliar spray. (confirm with an expert first)

[THC7]

Have sprayed foliar with epsom salt and still running straight water for now. Here are some picks.

[stinkyattic]

'praying for magnesium' is a myth. Leaf edges curling up is a classic symptom of heat stress. Magnesium looks like regular, pale stripes between veins.

Why did you use epsom salts on your plants? And it looks like yo used a LOT... those leaves have salt buildup on them. You need to spray them down with CLEAN WATER, avoiding letting any get in the res, or do it immediately before a scheduled res change.

Do your roots appear white or brown?

Your ppms are on the high side; bring them back down to 800 or so and work back up.

Get your temperatures at the canopy down below 85'F TOPS.

[THC7]

Ok, running straight waters PH 5.7 PPM 400. Roots are lilly white and massive. Let me put this in perspective, I have had the same setup for 4 years and only have had a total wipe out once 3 years ago and did not know the reason. Do about 4 to 5 grows a year and haven't changed lighting or highth of lights, chemical products have not changed and using GH by the book as I have done all along. Have not changed anything but differant plants. These are the same plants for the last 3 grows. This system is not small, I have 42 holes, 8' tubes, 4 1000 HPS lights and a 50 gal res. I am just trying to figure out what I have done wrong as maybe not cleaning out enough between grows, something got in the system, I just am dumbfounded and don't want to lose this one. Maybe this will help some, I hope.

[stinkyattic]

IT really looks like you are running your temperatures too high or your ambient humidity too low or both. It's that time of year, ya know? The air is really dry.
Rinse that salt buildup off your leaves, give the plants a nice light mist with SMC leaf shine (safe to use up to day of harvest- it's coriander oil), control your temperatures.
If the roots were brown I would say it might be a res contamination problem but healthy roots mean you are cleaning well enough between runs so no worries there.

Edit: One other thing I thought of is that it is a time of year when freezing and thawing leads to snowmelt and runoff, so your water chemistry may be different during the spring thaw- diluted by runoff or even polluted by road salt, depending upon its origin.

[THC7]

Thanks for the input. Went back to feeding and all looking better, drinking about 10 gal. a day since started feeding. I did have a problem with up and down ph problem for a week and that happens when we don't get much rain. Live in a area that the outside temps have averaged 60 and we don't have any snow here. Thanks again.