Hi everybody. I'm really hoping someone can help me identify this problem. I have read countless posts, talked to several hydroponic store owners, and read lots of information on how plants and nutrients interact. After tons of horticulture research I have a suspicion of what the problem is, but after screwing things up already I??ve decided to ask the community for advise on what to do.

I have seen many pictures of marijuana plant problems, but I have never a picture that looked like what I have. I am about 6 weeks into flowering. I wasn??t able to get a HPS setup until 14 days into flowering, so call it 5 weeks.

DOES ANYONE HAVE ANY IDEAS?

The Lowdown:

I am growing in soil. I chose Power Flower although I was told not to. Apparently it is for outdoor growers. ??Too hot,? they said. Well, the veg stage was incredible. Leaves the size of your head, excellent color, close node spacing, beautiful plants grown under 40w 5100k tubes. About 7 weeks into veg one of the plants (growing 5 different strains) started showing what??s in pics in the older leaves, starting at the bottom of the plant and slowly progressing up. Initially, I cut these leaves off as the problem appeared fearing bacteria or something crazy like that.

The problem has just now started appearing on the fan leaves on the branches, whereas before it was only on the fan leaves on the primary stem. ALL the buds on all the plants still show no signs. This problem has now progressed to every plant in the garden, starting at the bottom and moving up the plant. 15 days ago two of the plants starting yellowing significantly and it appears bud growth has stopped, or slowed to crawl on all plants. Most of the hairs have started turning brown prematurely. The petioles of the affects leaves are dark red/purple and more stiff than the rest, although not brittle. There are dark spots that dry out and turn into necrotic lesions that appear slightly different from plant to plant, which in about a weeks time turn to light-brown, paper-thin, waterless leaves that I eventually cut off. They are suffering?

How I think I screwed them up:

I didn??t use any fertilizer in the veg stage, because of the Power Flower soil, and because fertilizer is god-awful expensive. The soil bag says, ??No feeding required for 60 days? and its loaded with all the stuff one would normally mix together, in theory.

When I first saw this problem I went to my hydro guy with a leaf asking about the lesions. He said it looked like spider-mites (never had them) but he was more concerned with the purple petiole. He recommended Cal-Mag Plus. I read the direction aloud, ???with every watering? and he agreed. I recently did some research and found that it is a ??soil stabilizer? similar to adding dolomite lime to your soil, but I didn??t realize until then that I probably never should have used it. I use well water from a mountainous region. I just bought a TDS/PPM meter and it measures 75ppm. I found that Cal-Mag is really for hydro growers who use RO water??to turn it back into well water, and to compound things I??m growing in soil. I??ve been using it in every watering since the plants were 5? tall. I stopped using it 10 days ago.

And then?

About three weeks ago I finally invested in a bloom fertilizer, Advanced Nutrients Sensi Bloom Part A & B, assuming the nutrients in the soil had pooped out. I started with a 600ppm mix, the lowest one recommended on the bottle. I watered with the nutes and two days later there was a noticeable growth spurt. I got greedy and bumped up the solution to 700ppm and watered two days later (too soon). And then I had a few too many drinks,:wtf: and bumped up the solution to 1000ppm and watered lightly two days later (too soon again). So, two days after that, nute burn and over-watering symptoms! I waited three days and flushed them with four gallons of water each (they are in 2-gallon pots) and added more Cal-Mag to the water I flush with, like an idiot! That??s when I did my Cal-Mag study and found out I never should have used it.

The lesions are taking over new leaves daily and two entire plants (except the buds) have turned bright green/yellow.

The room stays between 75.5 F during light-time and 64.3 during night time. 50% humidity day and night. Excellent ventilation and circulation. Drinkable water of unknown mineral content/possibly high in iron, Power Flower Soil, Absolutely no mites/pests. The problem is not due to light burn or heat stress.

The 430w HPS lights makes for horrible pictures. I??ve corrected the color in a few of them. It??s interesting to see the same problem across different strains. Hopefully someone will be able recognize it. My research has led me to believe I have a potassium deficiency possibly due to lockout from magnesium, but its just a guess and the last thing I want to do is add more nutes and kill them?

Any help would be greatly appreciated! :hippy:
bobojones Reviewed by bobojones on . TRY TO IDENTIFY THIS NUTE PROBLEM! With Pictures For Your Viewing Pleasure... Hi everybody. I'm really hoping someone can help me identify this problem. I have read countless posts, talked to several hydroponic store owners, and read lots of information on how plants and nutrients interact. After tons of horticulture research I have a suspicion of what the problem is, but after screwing things up already I??ve decided to ask the community for advise on what to do. I have seen many pictures of marijuana plant problems, but I have never a picture that looked like what Rating: 5