Hi all, I am nearing the end of week 6 for a soil grow with GG4. Everything was going quite well until about a week ago when I noticed some burning tips and yellowing leaves. I use foxfarm ocean forest soil and the foxfarm fertilizers. I was foolishly feeding using the manufacturer's recommendations twice per week, so I think I almost certainly overdid it. I am pretty sure this is just nutrient burn? I flushed the soil and did a few waterings with plain, pH-balanced water only. I reintroduced quarter strength nutrients during the last watering session. The buds and surrounding leaves look quite healthy still, however, the older fan leaves seem to be mostly affected. Any suggestions? Probably 3 or so weeks left before she is finished, provided that she survives.
that tiger bloom lowers the ph when you feed to under 5 i learned the hard way too it doesnt look like they are very mature are they autos? i dont see any frost yet at all try to get your medium in the mid 6 range and only light feeding for a while
Thank you! They are photoperiod. I've noticed that as well, I think they should be a bit further along than they are right now. Hopefully I didn't break her!
6 weeks from flip, reaching the end of 6 weeks tomorrow. She was doing very well until one week ago and has been gradually having more and more issues with the older fan leaves. Just seems like the flowers should be further along now, I'm sure this has stressed her a bit.
I'm not a soil guy but I know it takes longer for it to dry up before feeding. It looks like a pH problem but could also be over watering and getting some root rot. You can see some leaves drooping at the tips like wet soil. I would remove all the damaged leaves and let soil dry to where you lift pot and feel it being lighter. See what happens in a week hopefully she recovers.
I would leave most of the leaves on and check your runoff ppm and ph can you check so you have a pH pen?
Thank you all. I've been using pH strips which show pH <6.2 with inflow water and runoff (no further discrimination on these particular strips), but I have ordered a pH pen to arrive in a day or two. I measured my runoff ppm and it's 200 which seems quite low. I think I overfed by giving full strength nutes twice per week, then I flushed, so now I don't know if this is residual leaf necrosis from nute burn versus a developing K deficiency following flush. I gave it a mild nutrient feed on last water (1/4 strength or so). I'm wondering if I should give it another 1/2 strength feeding next water (tomorrow) or just stick with plain water. Here are some leaves I removed today since they looked terrible. Any advice is welcome!!
Well every time it has happened to me I think 2 or 3 times in late flower the plants never recovered correctly and the smoke was low grade all the trichome production was halted and almost every leaf was gone by the 8 the week here's to hoping you better luck than me 200 is very low maybe give a small feeding
Yes you need to do a slurry test to know your ppm in soil. Take one shot glass of distilled water One shot glass of your soil and mix it up good and put your meter in it and see what it says. Under 400 is good over 400 is bad good number would be 350 check it out and let us know.
I'm hoping and thinking since you caught the problem and by looks of the picture your harvest can still be healthy as the leaves absorbed the potential risks
I'm starting to learn it's always a ph problem Sent from my SM-G781U using Grasscity Forum mobile app
Thank you all! I did a slurry test this morning, and the EC was 0.4 (200ppm on 500 scale). pH <6.2 using strips (still waiting for my meter to arrive). It certainly could still be low pH issue, but I won't know for sure until I have a pH meter. However, the soil seems to be completely leached at this point and the issue is rapidly progressing. Looking at the foxfarm nutrient chart, it looks like I was giving feedings of >2000 ppm (700 scale) twice per week. Then I overreacted when I saw some nutrient burn, and I flushed the soil which must have completely depleted the nutrients. I think what I am seeing now is a severe potassium deficiency since most of the affected leaves are older fan leaves and the plant is trying to mobilize potassium to the buds. Anyways, I decided to increase the feed today, so I gave a feeding of about 0.8 EC (400ppm on 500 scale); the runoff was around 0.6 EC (300 ppm). I'm only going to trim the leaves once they're starting to become necrotic since it seems like the plant is "eating itself" to supplement nutrition. Learning the hard way, unfortunately. I will be measuring pH and EC/PPM very closely on subsequent grows. I'll see if I can salvage this one, but I think the bud quality will almost certainly be affected at this point. Since the soil is leached, do you all think I should slurry test before each watering going forward? Then make a decision on feeding? It seems like if I were to give plain water on the next feeding I would just propagate the current deficiency.
Yes I think you over reacted and started to flush and feed causing a wet soil to where roots can't breathe and your plant looks the way it is. 200 ppm on a slurry test says your plant wants more nutrients. So I would just pay attention to your over watering which I think caused your issues. Your buds will continue to grow, might take a little longer before harvest.
Hi all, Just wanted to provide an update after receiving my pH meter. My plain water runs around 6.2 - 6.4 which seems to be appropriate. However, the addition of nutrients brings the pH down to 5.1-5.2 which is too low. I did a soil slurry which revealed a pH of 5.3. So as someone said earlier, it's always a pH problem! I was thinking of adjusting the nutrient solution to a pH of 6 and then feeding again at next watering. I will let you all know how it goes! The flowers seem to be doing okay, but still losing a lot of leaves each day. Will try to salvage, but I'm not going to be terribly surprised if it's too little too late at this point!
Yes if your pH is that low and you are in soil I wouldn't be afraid of doing a ph6.5 on next feeding.
Thank you everybody for your help. I treated my plant with pH 6.5 nutrient solution this am...the runoff pH was 4.8!! So, final diagnosis: nutrient lockout from acidic soil secondary to chronic overwatering and overfertilizing. This is my second grow; my first grow went beautifully and the main difference was I did not overwater the first one and I only fed once per week using 1/2 strength nutrients. This was a hard lesson to learn, but that is life I suppose. I will try to see if this one will go to harvest, but I'm already planning my next grow (with much less watering and fertilizing). I'll also be keeping an eye on my pH levels since I now have a meter! Thank you all again,