Top leaves yellowing from outside, then crisping and curling, mid to late flower

Hello everybody

I had some problems occur mid flower that prompted me to start a thread to receive help in the infirmary: https://www.icmag.com/ic/showthread.php?t=184012 I updated the infirmary form and it's at the end of my post so please refer to that for additional information.. I was able to take some better pictures before I harvested and I was hoping to get the community's perspective on what went wrong.

The general consensus was that I was overfeeding and to back off. Since it occurred so late in flowering, I switched to plain ph'd water until I harvested 11 days later. It seemed that the problem got progressively worse. I'm not able to move the plants to flush them so when I watered, I tried to get lots of runoff. The runoff ph was a little high (7-7.25).

In addition to the four 10 gallon pots, I also had a 3 gallon pot off to the side that I was flowering out to see how this strain did in low lighting. This plant got the same nutrient solutions as the ones under the light but did not exhibit any of the symptoms or problems. The fattest buds of the harvest came from this side plant. It looks like a plant should by the end of harvest:







What I don't understand is why this plant, which received the same nutes at the same time, turned out fine while the main plants were effected so much. One thought I had was that the 10 gallon pots had a lot of nutrients in the soil mixture that had yet to be used up. However, I didn't start feeding them until they started to lighten up a little bit and show some purple fan leave stems. Feeding fixed that. Also, if there were still nutes in the soil, wouldn't signs of overfeeding show sooner? The effected plants were in their 10 gallon pots for 23 days before flowering was initiated. The problems started to show about 10 days into flower, got pretty bad by day 20, and by day 35 it had become a full blown problem.


Here are some shots of the effected leaves:








I fed with Blue Mountain Organics Grow It Green, Flower Power, and Super Plant Tonic. I have used these nutes in the past and have had great success. They came very highly recommended to me. The company is very small, but some more information on their products can be found at http://www.angelfire.com/ar2/tts/bmogig.html. The general feeding schedule is to use some combination of Grow it Green or Flower Power that totals 1 tbs per gallon.

On days when I didn't feed, I watered with a worm casting tea. I typically tried to keep these pretty light on the ingredients and focused more on cultivating microlife.

Here is what they were received in their waterings:
6/3 Transplanted to 10 gallon pot, watered 1 gallon ph'd water
6/9 worm casting tea 1.5 gallons (3 gallons of water, 1 cup EWC, 1 tsp blackstrap molasses, 1 tsp maxicrop seaweed, 1/4 tsp humic acid)
6/13 Plant was getting a little light green and was watered 1.75 gallons with 3/4 tbs Grow It Green per gallon
6/17 worm casting tea 1.5 gallons (4 gallons of water, 1/2 cup EWC, 1/4c alfalfa meal, 1.5 tsp maxicrop seaweed, 1/2 tsp humid acid, 1.5 tsp molasses, 1/4oz Super Plant Tonic)
6/21 1.5 gallons of water with .8tbs Grow It Green and .2tbs Flower Power per gallon
6/25 1 gallon each plain ph'd water
6/26 Flowering initiated
6/28 1.15 gallons each with with 2/3tbs Grow it Green and 1/3 tbs Flower Power
7/2 worm casting tea 1 gallon (3 gallons of water, 1/2 c EWC, 15mL fulvic acid, 1 tsp molasses, 1/4 oz Super Plant Tonic
7/5 1.15 gallons with 1/2 tbs Grow it Green and 1/2 tbs Flower Power
7/9 1 gallon each plain ph'd water
7/12 1.15 gallons with 2/3tbs Flower power and 1/3 tbs Grow it Green
7/16 worm casting tea 1.5 gallons each (3 gallons of water, 1/3c EWC, 1/4 tsp maxicrop seaweed, 15ml fulvic acid, 1 tsp molasses, 1/4oz Super Plant Tonic)
7/20 1.3 gallons each with 1tbs flower power per gallon
7/23 1.5 gallons of water each, ph going in: 6.5, runoff ph: 7
7/27 1.25 gallons of water each with 1tbs Flower Power per gallon
7/30 2 gallons each plain ph'd water
8/4 2.5 gallons each plain ph'd water






And here's a shot of beneath the plant. It has stayed pretty green. This was my first attempt at a SCROG and I let it get overgrown as you can see







How long has this problem been going on? Started day 10 of flower, got really bad by day 35
What STRAIN are you growing? Green Crack
What was the establishing technique? (seed or clone?) Clone
What is the age of your plants? 120 days old, harvested at day 50
How long have they been in the soil mixture they are in now? 73 days
Were they in the same mixture when they were seedlings/smaller plant? If not, what mixture were they in before? yes, they were in the same mixture
How Tall are the plants? 35" total, woven through a screen that is 18" above the plant
What PHASE (seedling, vegetative or flower) are the plants in? day 50 flower
What Technique are you using? (SOG, SCROG etc) SCROG
What size pots are you using? (Include how many subjects to pot) 10 gallon pots, 1 per pot
What substrate/medium are you using? What brand of soil mixture are you using? (percentage of perlite, vermiculite...etc?)

Roots Organic Base
+10% Perlite
+1 tbs dolomite lime per gallon
+1 tbs mosquito dunks per 3 gallons

What brand Nutrient's are you using? Blue Mountain Organics Grow it Green, Flower Power, Super Plant Tonic Links to more info about these nutes http://www.angelfire.com/ar2/tts/bmogig.html
How much of each nutrient are you using with how much water? *Knowing the brand is very helpful* full strengh strength nutrients every time
How often are you feeding? Feeding schedule above
If flowering, when did you switch over to using Bloom nutrients? Gradually, schedule above
What order are you mixing your nutrients? (example: veg nutes 1st, bloom 2nd ect) bloom 1st, everything else 2nd.
What is the TDS/EC/PPM of your nutrients used? No EC tester
What is the pH of the "RUN-OFF"? 7.2
How often are you testing pH/ppm/EC/TDS? Test PH of nutrient solution and adjust to 6.5 before every watering. Have tested runoff twice.
What method of pH test was administered? Using Strips? pH pen? Liquid test kit
How often are you watering? 1-1.5 gallons every 3-4 days
When was your last feeding and how often are you feeding? Alternating between light worm casting teas and full strength BMO
What size bulb are you using? 1000w HPS
How old is your bulbs? brand new
What is the distance to the canopy? 20"
What is your RH Factor? (Relative Humidity) 50-60%
What is the canopy temperature? 77
What is the Day/Night Temp? (Include fluctuation range) 73-77 DAY 65-70 NIGHT
What is the current Air Flow? (cfm etc.) 375 CFM fan exhausting for 30 seconds every 5 minutes
Tell us about your ventilation, intake exhaust and when its running and not running ? On an interval timer, 30 seconds on 5 minutes off
Is the fan blowing directly at plants? No
Is the grow substrate constantly wet or moist? I water when I can stick my finger in the soil and the very tip feels very close to being dry.
Is your water HARD or SOFT? Hard water, PH of 7.8-8.5
What water are you using? Reverse Osmosis (RO)? Tap? Bottled? Well water? Distilled? Mineral Water? Water is run through a Tall Boy Filter
If using tap water, what is the ppm/EC/TDS of the water right out of the tap?(Only if you have a tds pen) Don't have a EC Pen
If using RO,Distilled,mineral water, what is the ppm/EC/TDS without any additives?(Only if you have a tds pen) No EC Pen
Are you using water from a water softener? no
Has plant been recently pruned, cloned or pinched? no
Have any pest chemicals been used? If so what and when? not recently, in the past, just neem.
Are plant's infected with pest's? There are some fungus gnat adults flying around. 30 flyers are stuck to a sticky trap thats been in the room for 50 days.

That's root aphid damage, not nutes.
you do not have fungas gnats.
you have the devil bug.
that's why it got so bad at day 25-35

get a scope and check the bodies out, are they striped like a tiger?

Interesting perspective, tr33... thanks! So Root Aphid infestations don't really exhibit problems until midway through flowering? I looked at the roots after the plants were harvested and I didn't see any dense white spots on the sides of the pot that I've read indicate a root aphid infection. These plants were very healthy throughout their extended veg. I have another round of plants under the light now that look very healthy and I was considering flipping them soon but if they are secretly infested with aphids maybe I should reconsider...

I have a sticky trap that I've been pulling off bugs from the look at under a 30x microscope... I don't see any stripes but the light conditions are poor. The wings of the bugs are smaller which makes me think fungus gnat but the body is a whole unit which I believe indicates it is a root aphid.

The yield off of the first trimmed plant was a pitiful 1.75 oz, plus a decent amount of popcorn nugs. The buds look like they didn't fill out at all... very crystally and great smelling, but just no weight. By far the worst harvest I've experienced...

Anybody else care to weigh in?

.

Here is a feeding chart I picked up recently for this line. It seems to work pretty well for most strains. I recently grew out some Chem D that needed 5 ml more grow it green per gallon, from veg to midway thru harvest. Otherwise, pretty well made nutes and fair prices. Hope this helps with future grows.

Root aphid fliers have 'tailpipes' - they are a definitive feature. I had them and I had that kind of burning, but I didn't have it on a plant that didn't receive treatment with a Sucrashield drench. If you have root aphids they don't stay a mystery - they will be crawling around in your trays in addition to flying. Look for the tailpipes, check out the photos in the beginning of the main RA thread. The fliers have a deep bluish tinge to them. A wide blunt ass with tailpipes on the outer sides, not close together in the middle.
Dense white spots are an indicator of a certain species of aphid, I think lettuce root aphids. I never saw those white waxy areas in the rootballs. I had aphids identical to the first photos in the RA thread - green bodies with reddish asses. Still haven't found a species id on them.

I also tried just water until harvest and it kept progressing.

I'm starting to sound like a broken record and/or conspiracy fanatic, but I am thinking there is a whole world of problems connected with mag shortages. The symptoms fit - interveinal chlorosis and tip burning, it would get worse from flushing, and a mag shortage results in much less yield. It would have been made worse by the RAs, if you have them. Maybe the leaves in more light show it most because they are metabolizing more?
Mine was really bad, but there were a couple plants that didn't have the same look, and they all had aphids.
I have a touchy strain regarding nutes, and when I go for more run off, it's going straight into showing mag shortage symptoms. Mag is easily leached -


Leaching and erosion are both principle culprits in losing available Mg and Ca from the soil,
dependant on a number of variables. Leaching of these nutrients often is much worse in acidic
soils. Management practices, including conservation tillage practices, can go a long way to
reducing losses via erosion.

from link -
http://www.kmag.com/pdffiles/news/magnesium.pdf

ISP - Thank you! I have a feeding chart that is very similar to that one that I received from Ohsogreen on another forum. This one looks more tweaked to our plants needs so thank you for sharing!

Albertine - I really appreciate you sharing your experiences! I'll look for the tail pipes more closely now that I know they are a definite feature to look for. I haven't seen many fliers around my soil but I see them crawling around the outside of the pots. Thanks for the clarification regarding the dense white spots. What did you do to finally eradicate them?

I treated with various substances, which cut the aphids back, but didn't eradicate them. I finished flowering the infected ones, and then took all the veg plants and put each of them on a card with a line of Tanglefoot around the outer edge ( These were placed on a bed of dry DE rock, so that they had no place to hang out over time). This kept the crawlers from moving from pot to pot. Any pot that they were in, I took cuttings from, and tossed the plant. Never saw crawlers on the cuttings. Fliers seemed to be limited to pots that I had tried treating and kept - related to the age of infestation. All eventually stopped showing up. At this point I haven't seen any for a month. I still have pots on cards - the Tanglefopot is a pain, but much less than the RAs. I am using crab and neem in my soil mix. Dr. Bronner's in a 2oz/gal will kill them fast, and is good for cleaning your pots, a shallow tray with it is good to work over when you are repotting and have soil spilling around.
Check the wiki entry for aphids. They spread by the already pregnant crawlers and fliers, not eggs. If you go with a physical barrier rather than trying to get them with chems, it is really simple - like fencing deer out of a garden. They show up really fast on the cards, at the beginning of an infestation. You can use squares of Panda plastic - white background, really easy to spot them. Totally worth getting set back by a couple weeks - go SOG with the cuttings and you can get back faster.