Hello all, to the first installment of -[Tricky's QUIZ]- If the response from threads like this are adequately helpful, I'd like to start doing these semi-frequently. Either way, I think they'll be fun and informative. The format of this show goes as follows: -I produce a very specific, real-life problem in the garden -Interested/knowledgeable growers can toss their input in at any time -Questions will be fielded -Tips/Tricks from experienced growers are given -A final, detailed summation of the problem will be reached when the conversation reaches it's limits PRETTY SIMPLE RIGHT? Let's get started. Thank you all for joining us today- I am your host, Tricky. Today's topic will be one many newer growers experience: HOW TO TELL THE DIFFERENCE BETWEEN NUTRIENT LOCKOUT AND NUTRIENT BURN. Today's test case is one of my friends', from 3 years ago. The setup is a low budget DWC with 2x 100w (equivalent) CFLs. The plant is indica dominant, about 4 weeks from seed, nearly showing sex, light LST was administered to enhance bud site production, supercropping was administered once each week, and a 3/4 strength nutrient solution of 30-10-10 had been feeding the young lady for a total of 5 days. The pictures are from the 5th day of this new N heavy diet. WARNING: THE GRAPHIC NATURE OF THESE IMAGES MIGHT NOT BE SUITABLE FOR SOME VIEWERS. STONER DISGRESSION ADVISED. #1-#3: Notice the fan leaves curling upwards, the interveinial chlorosis is set in throughout most of the new growth, yellowing and browning the tips of the leaves. #4-#5: Here are pics taken of fan leaves trimmed within 5 minutes. Notice the dark brown legions and necrotic portions between veins. The fat leaf was taken from about 8 nodes from the top of the plant. Since the plant was under LST, this leaf was near ground level, out in the open; a very viable fan leaf for the plant. Also notice the folding/curling fan leaves taken from the trim. The question is: Is this nutrient(Mg) deficiency (Nutrient lockout), or nutrient burn? How does one go about identifying the problem, and how does one go about correcting the problem? Clearly this plant has more problems than just the one, but this is the main focus of this discussion. I now leave this panel for open discussion, and I will be back after a short break. -Tricky
I would say mg deficiency with a slight burn. Mg deficiency causes the intervainial lightening and the brown spots. The tips being brown tells me its not quite burnt but its at the strongest nutrient level it can take. Not sure about the edges curling up, usually I would say heat but the top of the plant looked fine so its not that. I would fix it with calmag if using ro water or Epsom salts if using tap water
To me the "tacoing" of the leaves indicates a heat issue although I've seen similar issues resulting from MG being locked out. Whenever I seen multiple issues on a plant I think lockout.. That said, you indicated the plant had been fed for 5 days so nute burn probably should be ruled out so quickly.....
:BangHead: This is a trick question, isn't it? The real answer is 'who cares, it's not my plant' :kidding: But it could and probably will be one day so a little lesson will come in handy!!! Be Cool, CG
Ok Ok, Alrighhty! We're back! Thanks for your patience, folks! We are now back from our break, and I think we are ready to field some questions. Anyone? GreenJah- Many symptoms of Mg deficiency are similar to those of nute burn, it's hard to tell sometimes(as you probably know). This plant had a foliar feed of 1/3 tsp. of epsom salt per quart of water(I mixed it myself =p) probably 2 days straight at this point. I think you have a point about the 'strongest nutrient level' a plant can take, and I think we should talk more about it. .. So how can a plant have a bad burn and also Mg deficiency? Under normal circumstances, Mg deficiency locks out the intake of many vital nutrients- which nutrients would you say are too strong in concentration, and which would you say are weak(if any)? Duc- ADDITIONAL INFO: This plant had no heat issues(it was in a cool/neutral environment, around 75 degrees during day cycle) but was *recently* put on a strict diet of 30-10-10. You said you thought it was lockout- what would you do about it? Lion- Why? What makes you think that, and, if this were your plant, how would you correct it? At this stage of life, they don't really need an excess of K, a 30-10-10 solution should be giving ample K to a plant with freshly alternating nodes. Should I mention the root structure is absolutely gorgeous? I can post a pic of those too =p CG- I promise you the temp was super cool(68 night, 75 day), and from seed, the plant was given a 0-0-1 solution until it got bigger(the pics you see), when it got the increase to 30-10-10, so what would you do to fix it? Bee Are Bee after this short break -Tricky
Ph level is important, and it's the only vital issue you haven't given us. So is our lesson to start with the simplest , Ph, and work up to the more complicated? Be Cool, CG
Test the ph and ec of the water between and/or during res changes. The drifts will tell you where the problem is. Ph up ec down too low on nutes. Ec up ph down too high on nutes. Both up or both down means some kind of fungus. Bumping up from a seedling to full veg doses IN DWC UNDER CFLS is an especially bad idea, though generally speaking going gradual with fert changes and adjustments is the best idea in any system. Plants where the roots are submerged need lower amounts of nutrients in the water than plants that are watered on wet/dry cycles. 100w CFLs (I'm assuming 26w household bulbs not 105w spindle bulbs) are extremely low light conditions for DWC, which would aggrevate the condition. Final word - my vote is that if you test the ec/ppm of your res it's going to be higher than what you put in initially. Burn leads to lockout which leads to a worse burn in high water recirculating systems (DWC, NFT, Aero). Drop concentration from 3/4 full strength to 1/4 full strength and work up to the ideal ppm/ec for your plants. It's a problem you'll run into with any recirculating system but high water ones are the most touchy by far. What brand of fertilizer are you using? That makes a difference. For instance, floranova causes nearly instant precipitation in that sort of system and it's basically impossible to keep your roots happy. As a final note - I have NEVER foliar fed anything in a DWC system. It makes all the nutrients the plant needs very easily available if you're doing your job right. If the plants aren't happy then you need to deal with the cause rather than trying to treat the symptoms. Hope that was helpful ans sorry if I rezzed the dead.
Know your ph, know your temp range, and know they they are proper... Hard to say what's lockout or burn without knowing what the ph was, but then if you knew what the ph had been you'd know if it was lockout or burn. Happy Growin'
