Help with dying plants

Discussion in 'First Time Marijuana Growers' started by draines25, May 29, 2012.

  1. It seems like my plants are slowly dying and I can't figure out why. Here is the info:
    Indoor grow
    80 degree average temp
    plants are in 7 gallon pots
    plants are about 8 weeks old
    Strain: Pandora, Sour Diesel, Bubba Kush
    Soil PH 6.5-6.8
    Water PH neutral

    The problem is the fan leaves seem to be yellowing and dying, it starts by the junction of the leaf or at the tips of the leaf. The pandoras seem to be growing in height as new growth is definitely happening, where the other two seem to be slowing way way down. Half of the plants are being watered with miracle grow, the other half are all natural with fish in the soil and water only. The problem is affecting all plants. I have been battling some white flies and a few spider mites with neem oil, but they dont seem like they are that bad. Here are some pics, what do you think?




  2. How are you testing the PH? Also alot of new growers make the mistake of using Miracle Grow at full strength.
  3. What soil are you using?
  4. I am testing the ph with a testing kit I got at OSH. I am having the problem with plants that get MG as well as those that don't. I tried one week of no MG just water to try to flush to see if it would help those plants getting it, no difference.

    The soil comes from a local nursery and is called "215 Mix" and is tailored specifically for MJ cultivation.

    Any ideas?
  5. a local nursery that "tailors" cannabis specific soil :poke::laughing:

    That soil looks like it needs more perlite, the over watering/flushing might have made it worse, before they get better that is.

    MG is really garbage for MJ. You should be using at half strength most say, I say use it at 1/4 strength or not at all, a store bought organic tomato or plant food would be better. They even sell manure in a bottle concentrate for organic teas.

    They look heat stressed, with the curled finger leaves. the edges are deffinate deficient problems or nute lockout due to PH. are you testing the RUNOFF from the base of the plant?

    PH test the runoff then adjust the water to the PH needed. Get a digital PH meter off amazon $15 shipped, cant go wrong.
  6. Vicarious87, thanks for the ideas on ph, I haven't tested the runoff, but will do that next. If I have over watered, how long do you think I should wait to water again? These are 7 gallon pots and the average temp so far has been 80. I hear you on the heat stress, but it has been that temp or even hotter outside. I will stop using the MG entirely and check the runoff ph..............david
  7. We got a nursery a few miles from my house that has been there for several decades. They have a bunch of different stuff they can mix up for you, custom mixes, mixes to order etc...
  8. Well it does look to at least be a ph issue, and it seems to be from the soil. I got a good digital ph meter and found something very interesting. Reading at the bottom of the 7 gal pot I would get 3.5, then up near the rim I would get 4.5 and next to the plant itself I was getting 8.5 to 9ph! I am sure this is soil related because half of my plants have gotten NO miracle grow at all. Just not sure why the big variance in ph.

    So I got a product to mix in water to lower ph, I have watered 2 gallons of 5ph water per plant, twice over the last two days. Not sure how soon the plants will respond, they still look like shit and I don't know if they will pull through..........I sure hope they start improving!

    As a side note, how much water would you use for a 7 gal pot? How often? They seem to be pretty dry after 3-4 days so that is how often I water, just not sure......
  9. If you read the water that runs off and it is readying under 5.8 or over 6.8 that isnt good.

    If the runoff at the bottom is around 3.5 then adjust your water to PH 7.5 and it should buff the difference to around 6.0~6.5ph Add some superthrive or b-1 supplement to prevent shock and help them bounce back.

    After thoroughly flushing with 7,5 water then check again and let dry out for a 3-4 days straigh in 45-80 degree weather.
  10. What brand did you get and did you calibrate it? As for how much water to give it water till you have about 20% or so as run off out of the bottom. What kind of meter did you get?
  11. Could be a PH issue. Many cannabis issues are very similar so it can be difficult to figure it out.

    Heres a guide that might help.

    Cannabis Plant Problems & Symptoms | Marijuana Nutrient Deficiencies | Grow Weed Easy

    I find that many problems are solved with Cal-Mag supplement to your nutes. I add it everytime I nute. Usually no matter the nutrient type it tends to lack some..thats why most vendors sell Cal-Mag. Personally use Botanica Cal Mag. Stuff works wonders.
  12. The meter is a Luster Leaf 1845 digital ph meter. The odd (high) reading close to the plant was identical in all plants and even a eggplant that was in the same batch of soil. I'm not sure these plants will make it, they are looking pretty bad, even the eggplant is looking like crap.

    If I don't see improvement in the next few days, would I be better off transplanting them into different soil? Or is it better to try to nurse them along in the pot they are in?
  13. Ok, that explains alot. If you can take that PH meter back for a refund I would. When I was refering to a digital PH meter I should have been more specific as to say a digital PH meter for liquids. Not a soil PH tester. Cheap soil PH meters arent known for accuracy. Some of the reccomended brands for liquid digital Ph meters are Bluelab, Hanna and Milwaukee. The only really accurate soil PH testers I have seen used start around $400.00. Those were loaner ones my nephews were given to use in their high school agriculture classes and at a nursery their agriculture teacher runs. For a digital liquid PH tester you would need some calibration solution for it and some PH Up & Down solutions.
  14. Well I have a chemical kit for testing liquid ph, got the meter at a local grow supply store. They did not have any ph testers of any sort that were 400.00, and I wouldn't have bought one if they had.

    In your experience are the chem kits for liquid ph testing not accurate? I did get the ph up & down solutions. They advised watering at 5ph and check the soil ph with the meter.
  15. Unless I was doing it for a living and not a hobby theres no way I would pay that much either. Amazon and Ebay are good places to look for an affordable liquid digital PH meter. The liquid chem kit should give you a general idea but for better accuracy thats where the digital liquid PH meters make a difference. Who said water with a PH 5? I would water with a PH of 6.5 and test the run off before doing anything else. Milwaukee has a basic starter one for about $20.00 and should last a few grows but sooner or later it will pay to invest a little more and buy a good one. I have a Bluelab Combo Meter that I paid $226.00 for and have no regrets. I get fast accurate readings in seconds and Bluelab have the longest warranty on the main unit at 5 years most other brands are 1-2 years on the main unit and the standard 6 month warranty on the replaceable PH probe. Some of the cheaper ones may not have a replaceable PH probe.

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