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blazer23
03-07-2011, 05:49 PM
I've read a lot about the yellowing and browning of leaves and what it could be. But am still not sure with my situation. They started just at the bottom and a couple of small leaves have died. But on a couple of plants the yellowing has seemed to spread and brown spots have developed. I'm almost 4 weeks in veg. I'm leaning towards too high ph, but I'm also worried about nutrient levels. I've been going a little above 7.0, at most 7.5. I thought it was good to have right on 7, but now I'm reading a lot of people are going lower for soil growth.

I have copied and pasted this trouble shooting page I found:

What is your experience level? (first timer, novice, experienced...) first timer

Your Equipment:
.1) Type and wattage of lights. (MH, HPS, CFL's, tube fluorescents, LED's) 2 MH 400 watts
.2) Distance from tops? 1 ft, maybe 1 ½ ft.
.3) Reflector type? (cool tube set-up, bat wing, enclosed reflector, bare bulb...)enclosed reflector
.4) Is there a consistent fresh air supply?yes
.5) Do you have an exhaust fan and a circulation fan? yes
.6) What are the bulb wattages, kelvin ratings, and schedule?

Your medium:
.7) Specific brand and type of soil, (coco, peat based soilless...) and anything you've added to it. (vermiculite, perlite, worm castings...) Pro mix, watered with Great White when first transplanted to 3 gallon bucket
.8) Size of container.3 gallon
.9) Did you use peat pucks (or similar) to root clones or germinate seedlings?germinate seedlings

Your nutrients and water:
10) Source of water? (tap, bottled or filtered) What's it's ph before adjusting?tap, 7.2-7.5
11) Method of checking water ph. (ph pen, test strips, aquarium test kit...) ph pen
12) Method of adjusting water ph. (phosphoric acid, white vinegar, hydrated lime, PH Up...) PH up, down
13) Specific brand and N-P-K ratio for each bottle. List dosages (quantity per gallon) and current feeding schedule. Flora Micro, Gro and Bloom / one tsp each in 5 gallon bucket of water. Watered 15 plants in 3 gallon buckets
14) How often are you watering between feedings, and how much per watering? Watering every third day with 5 gallon bucket of water, only gave nutrients once about two weeks after transplanted.
15) Any additives or tea's? (Superthrive, CalMag, molasses, Mother's Earth...) just great white
16) Are your ph levels stable, or do they fluctuate? fluctuate
17) What is your ingoing water's ph? ...your runoff ph? 7.2-7.5, haven't really done much ph adjusting, haven't checked runoff
18) Do you foliar feed? If so, with what, how often, and at what time do you spray? No, just mist with regluar water

Your growroom:
19) Indoors or outdoors? Indoors
20) What size of closet, room or hut? 4x4x7
21) What are the temps and humidity levels while lights are on? ...With lights off? On 24 hour light schedule. Temps have been 75-78 and humidity has been 38-45 mainly.
22) Have you seen signs of insects in the growroom? One tiny bug once

Your strain:
23) What strain are you growing? (Indica dominate or Sativa dom?) peanut butter?
24) From seeds or clones? seeds
25) Is this an autoflower strain? ???

blazer23
03-09-2011, 04:33 PM
Can anybody help me with this?
I waited until plants were really dry and did a thorough watering with a adjusted ph of 6.8. I've got five plants that are like this and have noticed a couple more leaves with yellowing and brown spots.
What should I do?

Rusty Trichome
03-09-2011, 06:07 PM
Growing in peat-based mediums requires an ingoing ph of between 6.3 and 6.8 ph. Higher or lower than that and you'll start to lock-out nutrients. (causing the leaf yellowing)

Check online for proper feeding ratio's with your Flora products, and follow the weekly schedule. (http://www.generalhydroponics.com/genhydro_US/feeding_charts/GO_MYSF-FeedChart.pdf

But yellowing with brownish-grey spots is a sign of overwatering. Feeding is most important, so only water inbetween feedings if the soil is almost completely dry.

blazer23
03-19-2011, 03:34 PM
Okay, have cut back on watering and added one tsp each of the nutrients described above at my last watering three days ago. The leaves are still yellowing and have lots of brown spots. I'm nervous that they are going down hill quickly. Since I had never tested ph from the soil run off. I watered one plant with about 2 gallons of 6.8 ph'd water and it gave about a 10% run off. I tested that and the ph was 6.1. Isn't this the high end of normal?

Is it possible now that the issue wasn't with a ph problem causing a lock out?

Help :/

Rusty Trichome
03-19-2011, 03:48 PM
Did you check the online schedule and start following it?

What does the new growth look like? Old leaves are old news, and they don't heal. They'll keep fading.

How are you testing runoff ph? If you're not using a ph pen, likely your numbers are off.

You'll want to keep the ingoing water between 6.3 and 6.8. I aim for the upper-end, (6.8ish) since adding nutrients drops it further.

6.1 ph is a tad low, not a tad high. (unless you're in coco or running hydro)

Like I already mentioned, it might well be overwatering. Provide pix, and perhaps we can see...

blazer23
03-19-2011, 04:55 PM
I checked the link you gave me, but didn't see the exact products I was using. There is a feeding schedule on the bottles I am using. At that last point it did seem like we were behind schedule with the nutrients because we were doing quarter strength. (Because we used pro mix we were told not to do much fertilization at first.) But this time we used the instructions for mild vegetative growth (even though I think we should have been at aggressive vegetative growth at that point). Next time we add nutrients, which I'm thinking will be one week from last time and we'll do the schedule for aggressive vegetative growth.

New growth looks more of a brighter green. Then some of the leaves towards the top have started to yellow.

Definitely using a ph pen. Water going in is now only 6.5-6.8. What should the ph run off be for soil growth then?

I thought I let it dry out enough, pots were super light and I couldn't feel any water after sticking my longest finder all the way in the soil. But perhaps I am still over watering.

I want to provide pics as soon as I can. I let my friend borrow my camera and still waiting for it back! But I definitely agree so far that I should hold back my watering and get on a better feeding schedule. It's definitely out of wack at this point.

blazer23
03-22-2011, 02:53 PM
Okay I finally got some pics. Check them out and tell me what you think. We just moved the lights up a little bit and gave them the aggressive vegetative nutrient feeding, with little water. (Which was almost a week from last time we watered/fed). Let me know if you need some more pics, some of the ones I took I couldn't get to attach.

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