Hi guys, Thanks for stopping by, I hope you can help me! I'm an indoor cabinet grower with years of soil growing experience. I've been growing this atomic northern lights strain for years without issues, but I just upgraded my system to DWC hydroponics setup (in a storage tote) and I'm having a couple of hiccups during my first grow that I really hope you can help me resolve. 1) THRIPS (pretty sure I've got this beat) I have a jewlers loop and I'm almost 100% certain that I have/had thrips. As stated in my questionaire response below, I've begun a 4 pronged attack (neem oil and insecticide spray, sevin insecticide dust, doctor doom foggers) with a plan to apply a different treatment every 3 days for a total of 2 weeks. So far, I've applied a mixture of neem oil/insecticide spray as per the directions, and then 3 days later I used a doctor doom fogger. The thrips seem to be slowing down. I cannot see a single live one on any of my plants (but a few dead ones!), but I will be continuing my treatment for the full 2 week course. Pretty sure I have this under control, but now I think I have a new issue: 2) STRANGE, GOLD COLORED LEAF DISCOLORATION This is the main reason for my post here. At first, I thought that this discoloration was a result of the thrips attack, but now I'm not so sure. I'm hoping someone will be able to help me diagnose if I have an additional (possibly nute deficiency or lockout related) problem? Before I get to the pics, I should explain: I cut most of the dead and dying leaf matter off the plant this morning. The main reason for this was fear of moulding (apparently thrips feces can mold). In my haste, I forgot to take pictures of the plant damage before the leaves were removed. Additionaly, I'm hoping that removing the dead plant matter would help me spot any new, worsening symptons. I've included a pic of the "chopped" matter to give you an idea of what I was seeing... Wish I hadn't been so hasty, but what can you do... After a lot of reading, I'm worried I might have a Phosphorus (P) deficiency? Calcium deficiency? I'm confused, I'm using the lucas formula and my PH has NEVER been out of the 5.1 to 5.9 range, it is usually around 5.6 to 5.7 ish... I read that phosphorus requires a PH of 5.8 and above to be absorbed? TBH though, that's just a guess. I really don't know! What type of medium; soil or hydro? Hydro - DWC, tote reservoir holding a total of 11 gallons. Clones rooted in rockwool, planted in 3 inch pots of hydroton. Brand new system, first run. (Rena 400 Air pump, 2x 4" hydro air discs) Indoors or outdoors? Indoors What strain? Dr Atomic Northern Lights How old are the plants? Rooted clones were placed in the system a total of 3 weeks and 3 days as of today What type of lights and how many watts? Cool tube 250w, digital ballast, current with 250w Metal Halide bulb How far from the lights? 4" What is your watering frequency and source of water? Tap water, very good quality. 7.20 PH, 16PPM, been using the same water for soil grows without issue for years. Water is always left out for 24 hours before use. What, how much and when was it fed? NPK? I'm using the standard GH Flora Lucas formula + floralicious plus + cannazyme. Week 1&2: 50% strength Lucas formula 0-4-8 +1ml/gal floralicious plus (469PPM @0.5) Week 3: Dump and clean reservoir. Full strength lucas formula +1ml/gal floralicious plus +9ml/gal cannazyme (850PPM @0.5) What is the medium/runoff pH and PPM if in hydro? Everything seems fine. The PH slowly and predictably drifts between 5.1 (right after adding nutes and cannazyme) and 5.9. I check the system every day, it has never been out of these ranges. (PPMs listed above) What are the temps and humidity in the room? Humidity approx 65% Temp: Approx 25 degrees celsius Reservoir Temp around 24.5 Celsius with the lights on What size pots? 3" net pots Any bugs? Look real close. Yes - Thrips (My first experience with thrips, but I have a jewlers loops and am almost 100% certain after viewing the bugs). I began treatment of the thirps as soon as they were diagnosed. I have purchased insecticide spray, neem oil, sevin insecticide dust and doctor doom foggers. I've already run two treatments (1-insecticide and neem oil spray applied directly to the plant and sevin dust on the top of the hydroton. 2- Doctor doom fogged the cabinet. I plan to continue to repeat my treatments every 3 days for a total of 2 weeks. Any other pertinent info? Yes. This is my first DWC grow, I just upgraded my system. I'm an experienced soil grower of many years, I have been growing this particular strain for the last 3 years and never had a single problem. I take a "no expense spared" approach to my hobby, I have a great PH/PPM meter and have grown physically in the same spot for years.
Thanx for supplying us with so much info. I wish more would do like u . I will tell u tho, right off the bat... U will have worse than leaf discolouration if u are planning on using 4 different products within 12 dayz. This is sure to damage the plant and screw up the medium. I advise u to choose a product best suited to you and the plant and the offender and stick to it. If it fails, then move onto another product. Never mix insecticidal chemicals. One chemical can neutralize another or itll attack the plant. Go with the Pyrethrum fogger. It will take them out in 1 shot, and clean out the space too. Freak
Thats some sound advice, thanks. Do you think the yellowing is damage from insecticide? Has any one else ever seen this reaction?
Youre takin real good care of those plants and it shows, so kudos . I cant see anything your doin or not doin that might contribute to the yellowing. I dont think its a big issue. It might advance further, to a little burning, but nothing major, so dont sweat it. Just make sure u use insecticides consecutively - never in unison. Freak
Ok, so an update to my situation. The following day, the yellowing had progressed severely, and the leaves had actually turned white (in between the veins, the veins were still green) On a hunch, I bought some Botanicare CalMag Plus and added it at 50% strength (2.5ml/gal). I took day-to-day comparison pictures, and the yellowing/whitening pretty much stopped immediately (the leaves still show the initial damage, but that's to be expected). I think I'm one of the rare people who's tap water is actually TOO pure, not containing enough calcium and/or magnesium. In retrospect, a few days prior I had noticed the leaves "praying" (leaf margins raising, kinda folding together in the middle). It looked a little like heat stress (despite my cab being at an ideal temperature) and I disregarded it. I'm pretty sure now that was the first sign of a magnesium def. The whole thrips problem at the same time threw me for a loop, making everything harder to figure out. I'll be upping the CalMag strength to 100% (5ml per gallon) at my next addback.
Theres a saying that us oldskool growers usedta use back in the day... Praying for Magnesium. Aptly worded, huh ??? Freak