Long story short I had had pretty good luck up until now although this issue has been presenting for a while. The yellowing leaves that look like nitrogen deficient to me. Are they though. Do I need to up my feed? If so can someone give me the proper way to proportion this. I was just kinda using their numbers and adding extra of the 3 base nute to up my ppm in similar ratios.
I was trying to go along with an aggressive feed as listed on the gh chart. Using GH nutes The ppms were not adding up though. The thing would say so many ml per gal and I would put those and it would be hundreds of ppm under what it said it should be. Plant is lake tahoe other is unknown the lake tahoe has the most yellow. Temps 75-80 day and 63-70 nights depending on temps outdoors (warm winter) and humidity 60-65 in general. 4x 250w quantum boards.
My water starts at about 80ppm to which I add. silica mad farmer around 20-25ml per 5 gal, calimagic approx 20-25ml per 5gal, micro- approx 50ml per 5 gal, grow approx 50-60 ml per 5 gal, bloom approx 70 ml per 5gal, koolbloom approx 8 ml per gal,florablend around 30ml per 5 gal/. if I used their numbers for ml per gal I end up with 400 ppm. I don’t do a couple things on the chart but my ppm came up to 820 or something last time and my runoff is approx 950.
You really don’t want to feed nitrogen this late in flower. Those lower leaves that are pure yellow do look like a nitrogen deficiency, but there is also natural dying of the leaves too.
Overall the leaves do look light, but the coloring isn’t very easy to tell under that lighting. Buds are stacking nicely, water pressure in the leaves seem good.
The color seems to be all over the plant, so its not indicative of a mobile nutrient (old leaves) or an immobile nutrient (newer leaves).
Sometimes it is a micronutrient like sulphur that can add a little color back into the mix.
I am into week 4 right now or beginning week 5. Should I just cut the nitrogen completely? Or lower it a lot? It is kinda strange as I hadn’t ever really had this problem before. What is the best way to add sulfur. I have never used it.
They aren’t hardly as bad as in the photos I wasn’t thinking and didn’t turn the lights off but they show it somewhat. I wish I could add a couple more to better show. After reading your comment and the one below, I believe it could be ph above all. I feel silly not checking the ph of the runoff now. It is showing 5.5 or maybe a bit lower going by the drops I use. I was trying to get it around 6 to water and must have been off some.
I’m not sure what amount you are adding, but yes, cut it significantly. You could get away with cutting it out all together at this stage of flower.
I’ve used epsom salt as my way of getting sulphur into the plant.
If using soil, your run-off isn’t an accurate picture of root zone pH. If it is coco, then yes, it would be more accurate.
Cool, thanks. I have some epsom I just never really used it on them because of the cal mag. Today is a water day so I will throw a bit in and leave the ph higher. I have it in coco RG tupur. I had been feeding around 10 ml or so a gal of grow the feed chart for the nutes had it at 5.7 ml per gal for week 4 and i was adding more to up my ppm. Did that with all the nutes.
Here is my main issue with the nutes… How in the world is my ppm supposed to be high enough. It only comes out to like 400 ppm if I got by the chart but says it should be like 950.. I have always been confused by this. I need to review some of my older posts if they are still around.
Have you double checked on your ppm using more than one device?
Definitely agree with Chad, you do not want nitrogen at this point as it will divert a lot of energy to process the nitrogen when the plant is wanting to use that energy to process metabolites. I have see plants look like this before when the pH was off and or potassium was lacking. Do you know the pH of your run off? This could be what is causing issues.
The photos are a little washed out as i forgot the lights but I believe you are right. I checked the runoff after reading your comments and it is low 5 or 5.5ish. I will correct that next watering best I can… What do you think water in at aboout 7 or 8ph? I gave them some recharge last time but not much as I am bout out hope that helps some. I feel like such a newb forgetting about checking runoff ph completely. It shows I haven’t been here for a while. LOL.
Should I just cut the nitrogen completely. I have always kept a little bit of that grow bottle in the mix but they all have N in them.
This is my first go in a long time not using my far reds the entire time for emerson effect. The plants are a lot smaller and seem to be much slower but I wanted to see how it went without it. I was just thinking that was the issue before. I am always confused on the amount of light too. I have two 250w qbs over each plant. Not sure if they are too close or too high or just right.
Lol the site didn’t take my reply twice now. I copied it this time so hopefully it will go through.
If you are in coco I would consider a flush and then start refeeding with a pH of 6 and keep the PPMs maxed at 600 (EC of 1.2). If you are in soil then I would defer to other dgc with soil growing experience since I lack that. I would only use bottles that have low nitrogen which should be your bloom bottles. Ideally no nitrogen outside of amino acids at this point but I understand you have to work with what you got. I am unfamiliar with GH but if they have a simple feeding regimen then maybe consider following that. It’s good to remember nutrient companies want you to use more than needed so you will get more nutes at a faster clip. Sometimes less is more. I use water soluble potassium sulphate for a mid-late flower boost to help aid in terpene production and the extra potassium is usually needed down the stretch.
As for your lights, it is possible that they are contributing to the issue as well. My question is how big is your grow space? I ask because it seems you have enough light for a 4×8 space. So if you are in a smaller space than 4×8 and your lights are full blast then light stress could be a potential factor. Generally 250 watts per 8 square feet is fairly average. As for the hanging height a general rule for quantum boards is 18-24inch off of canopy and if they are large and high powered then 36 inch off canopy may even be reasonable. Hope this helps and let us know if there’s any other questions you have! Besides the lighter color the flowers are looking plump so you still have something to look forward too. Happy growing and #growerslove
Thank you I appreciate the advice. The gh feed chart has you using the grow bottle which is a 2-1-6 up until week 8 where the chart says 1.9ml per gal. The micro is 5-0-1 which is the base nute and the bloom is a 0-5-4 and I have a bottle of crystal burst which is like 0-0-15 and I just put about a 1-2ml per gal. The feed chart is my prof pic lol but I don’t think I can zoom it. lol
I need to actually measure the lights and how far they are above. I believe they are close to that but I do have them turned up. These are on a rheostat so I turn them all the way and back it off a hair. With 3plants I usually put a 5th one in there but I only did two this time. Glad I am not overdoing it too much. The plants def grow way different without those two qb52 720nm lights running all day. I wish I had kept a good record it would have been a decent experiment. Maybe next time lol. Great yields vigorous agressive plants, excessive stretch.
The one plant that I know said 8-12 weeks which is hard to judge for me but It is about time to start adding the mendicino avalanche for the one that gets there in 8 hopefully the other is close as well. Knowing when to cut is one of the hardest things for me even using my loupes.