Potassium?

[Ncogneato]

First grow
2 girls AK48
soil: peat base with WC and perlite
organic amendments: bone and blood meal, WC, dolomite lime
PH: 7+-
organic ferts: Alaska fish emulsion, Neptunes liquid kelp, indo bat guano, molasses
temps: 80 +-
vegged: 60days
light: 1000w HPS
18 days flower
1 seed, 1 clone


These are my two AK48 ladies. I have been having trouble with both since late veg. The problem started with some rusty burning on the edges of the lower fan leaves. The necrosis then moved inward toward the center of the leaves. Veins are still green. The problem started on the lower fan leaves and over the course of 3 weeks it has spread throughout the whole plant. I flushed once about 4 days before 12/12 with no noted improvement. I watered with diluted fish emulsion, kelp, quano, molasses, and epsom salt (1tblsp. per gallon). I am using RO water. I keep second guessing myself as to whether I am deficient on Phosphorus or Potassium; or perhaps I have overferted and burnt them up. I think I have now narrowed it down to a potassium deficiency and/or possible micro nute deficiency. Therefore, today I flushed again (just for good measure) and then watered with a full strength dose of Neptune's kelp, 1/2 tblsp. epsom and 2cups of worm castings in the form of a tea. Any advice or suggestions are greatly appreciated as I am smokeless now I don't want to completely screw up my yeild of medicine.
Here are the pics *hopefully*

 

[ph6.5]

howdy
you stated that the ph as 7+-, is that the ro ph or the runoff ph?

thanks

ph6.5

 

[Ncogneato]

Not sure. I use a cheap soil probe that always reads between 7.4 and 6.6. I assumed that with the 2tblsp. of dolomite lime per gallon of soil mixture would hold my soil steady at near 7.0

 

[duce]

u need to find out the ph of your water first.go down to wal-mart and get the 10 in one fish strips or go to the water purifing dept.and get the pool test strips. they will both give you a good reading of your ph.your plants probally have a nute lockout/due to a ph problem.do u know how important ph is to your plants? and the way the plants pick up the nutes you feed them?
get a good reading of your ph.no one is going to be able to give you a good anwser till then
good luck

 

[Ncogneato]

O.K. , I got the pool test strips. I checked the PH of my RO water which read 6.8. Ironically, the test strips only test as low as 6.8. I am thinking I just wasted $11.00. I will try to test my runoff, but I'm thinking that the discoloration of the runoff will adulterate the accuracy. I just need to break down and purchase a good PH pen. Any suggestions on an accurate but affordable tester?

 

[Getawaymonkey!]

check ebay. you can get some decent ones on there for around 25 bucks. Stay away from Hanna checker1's at all costs

 

[10k]

I'd suggest the hanna "pHep".
Very nice pH (and temperature) pen with all the desirable bells and whistles.
A bargain priced unit imho considering all it's handy features.

 

[Blackmelo]

just looking at what you are feeding should give ya a good indication.
You are feeding it loads of vegg nutes and vegg boosters. I don't see any flowering nutes...
So without even looking at the plants I would tip on a Potassium and Phosphorous deficiency.
Good advice from the others too.

 

[MynameStitch]

looks like you possibly either have a calcium deficiency or a severe ph problem

you may either have a ph problem causing this or you overferting causing lockout of calcium


how often are you feeding your plants and how much and are you using more than one at each feeding?

but either way it looks more like you have burned your plants and locking out micros

potassium usally stays out of the edges of the leaves, i havnt seem them work inwards except yellowing of the inner leaves where the outter edges stay redish brown color

calcium spreads all inwards in the leaves leaving spotty like syptoms on the leaves that mimic ph as well

so you may have a few problem,s here and im sure most likley due to the overferting

 

[Ncogneato]

About once every third watering I would water in with 1tbls. fish emulsion, 1tblsp. kelp extract 0-0-1, 1tblsp. molasses. Once I started to notice the discoloration on the leaves, I began adding 2tbls indo bat guano 0.5-12-0.5 every other feeding. And I started mixing in 1tblsp. epsom salt. All of these ferts were mixed together and fed to my girls at once. At this point, I am at day 40, all of the leaves on the large plant are yellow and curling. However, there has been some decent bud formation and she is packing on the weight. The smaller plant has the same condition but it is not as severe. I will have a decent harvest but not nearly as good as I know it could be.

 

[Desiderata]

About once every third watering I would water in with 1tbls. fish emulsion, 1tblsp. kelp extract 0-0-1, 1tblsp. molasses. Once I started to notice the discoloration on the leaves, I began adding 2tbls indo bat guano 0.5-12-0.5 every other feeding. And I started mixing in 1tblsp. epsom salt. All of these ferts were mixed together and fed to my girls at once.

Ncogneato, there's your problem..........way too much fert at one time. You should be using teaspoons and even at your frequency of feeding that is still too much food. You should just flush from here on out until you get almost clear runoff. Your runoff has got to look like dark pee.

You did say your at day 40........your on the borderline of very little food required at this point until harvest, imo.......I would flush with a 1/2 teaspoon per gallon of hydrated lime to provide calcium and neutralize your PH. Then see if they get somewhat happy again.........probably your damaged leaves will crisp out from here tho.

No more ferts for awhile bro!

 

[Ncogneato]

Thank you everybody. Next grow is sure to be better.