My plant is almost through it's fifth week. The strain is Critical Autoflowering. I'm growing in 8 part FFHF, 2 part Perlite. Temps and humidity levels have typical been in good ranges. I just started providing low levels of nutrients 2 weeks ago. I started with under a half dose of Dyna-Grow Foliage-Pro and worked up to half a dose about a week ago. At that point in time I noticed a bit of nutrient deficiency so I supplemented the half dose of Foliage-Pro with half a dose of Cal-Mag Plus. I've been feeding the plant half a dose of both products for 2 waterings now. At this point the plant is still showing signs of nutrient deficiency on a select few of the bottom leaves, and I have a bit of nutrient burn at the top of the plant. Other than that, things seem to be going well, but I figured I would check with more experienced growers here. I do plan to switch to Dyna-Grow Bloom soon since the plant began flowering about a week and a half ago, but I worry about ending up with premature nitrogen deficiency.
Are you checking ph of water? Do you use cal mag, they look good but have a deficiency in cal mag or potassium they show up together alot.
I PH the water to 6.5. I don't usually check the runoff PH, though. I just started watering with Cal-Mag Plus a week ago. But I am only using half a dose so far. I was under the impression that autoflowering strains needed less nutes in general.
Needs some nitrogen, usually not needed as much in flower stage but the leaves are kinda yellow, also cal-mag. Besides that she looks good.
Both Dyna-Grow Foliage-Pro and Cal-Mag Plus contain nitrogen. Do you think I need to give the plant even more?
yes, I was feeding at 6.5 last couple weeks ago... but my runoff has been getting lower, and lower, and today it was 5.2 after feeding 7.1 solution. Glad I am keeping an eye on it
If the question was not answered already you check the ph of run off to make sure the soil itself is at the ph you want, which in turn lets you know how to adjust what is going in to fix the problem if there is one. I prefer the slurry test it gives more accurate results. If you are not familiar with this test what you do is dig into soil about an inch or two when your soil is dry and ready for a watering take a small sample of the dirt 2-3 pinches and mix equal or 2/1 water/dirt ratio, 15 min later check ph and ppm should be a true reading of where the soil is at. Ph run off is sometimes misleading.(you should still double check with run off or at least I do) the run off is then disposed of not recycled through.
Ah, got it. I'll have to try that out. Do you guys think I should switch to using bloom nutrients now? Would that help with the deficiencies that I'm seeing?
yes feed bloom now, and again, please check the pH of the soil. as @Popcorn explained; you should re-read the post I wrote, my experience... see, if I had not been monitoring the runoff, I would still be feeding 6.0 solution, but what would have happened to the media? It would continue to acidify until nutrients were locked out and/or roots were damaged. By monitoring the pH, I am able to correct problems before they arise.
These guys are right. My soil ph drifts down to mid 5’s. We know we need to keep it ABOVE about 6.2 because that’s when my plants start to struggle with nutrient intake. I’ve taken to watering with water phd to around 7-7.3 ph to bring my soils ph up so my plants have no problem eating all their food. Ideally we want the soil about 6.5,, but unless you have lime or a soil that adjust ph itself, you’ve gotta continuously adjust as your plants use up the available nutrients in the soil at any given time.
I'm really thankful for your replies . I just looked at the runoff PH. It's all the way down at 5.7ish! So my plant is probably having trouble pulling any nutes from the soil. I don't have any soil PH adjustment products. Will watering the plant at a higher PH actually help? Until I get my hands on Dolomite Lime would you recommend applying nutes via foliar spray?
Yup, you won’t be adding anything so don’t flush, just give her a nice healthy of higher ph. Personally I adjust by the amount I’m off. So if I want my ph at 6.7 and it’s at 5.9 I’m going to water with a ph of around 7.5. Check it, it’ll get up maybe to 6.3, next watering or feeding, I do it again.
Got it. Unfortunately I already flushed today because I have been providing the plant nutes for a few weeks up to this point without doing so. Any thoughts on foliar feeding or introducing a soil PH adjustment product?
This can be tricky. I am not a fan of flushing as I find it wasteful and potentially detrimental to the plant's health. You already flushed, so not too much mineral buildup, but the pH is dropping. What I've done before following a flush is prepared a solution with appropriate calmag and rinse the solution off and collect everything. I check the pH and increase it with pH up (or potassium hydroxide actually, you can and should make your own) and then run it through again. I repeat this adjusting the pH accordingly each time. It took many rounds, like a dozen, but eventually the runoff stabilized. I then discard the solution and then flush with the appropriate pH'd and normal nutrent solution (enough to flush completely). As far as I know, this is my method, so don't expect to find it online. I think I will be using it again soon on my own plant, although she's still happy so I'm not too worried about it (she likes it hot). If you are in soil or peat moss based media, then add some dolomite (gardening) lime to the soil, they have time released pellets nowadays. Do that if you transplant (along with perlite).
I should add though... I've been feeding 7.2 for days now and the runoff has been rising. It just takes time, and if you don't need an immediate fix, then just keep watering at a higher ph and monitor your runoff. PS its good to monitor your EC as well Good luck with it
If you are growing in FFHF, then you should use some type of camg from the get go, as it doesn't have much ca or mg in HF or OF. I use GH camg+ and for seedlings I use 2ml per gallon, otherwise I use 5ml per gallon whether feeding or just watering all the way to the end of week 6, then I do one more week at 2ml, (week 7), then I cot them off completely. Unless you are growing organically, where those supplements are in the soil, calcium and magnesium should always be part of your feeding program.
Alright, some updates on my issues - I gave my plant a light foliar feeding Tuesday and yesterday with low consistencies of Dyna-Grow Bloom and Botanicare Cal-Mag (~35% of each). Also, yesterday I was able to purchase and water the plant with a liming agent. The runoff water was still at a PH of 5.8ish. I have heard it will take a couple of weeks for the liming agent to activate. I am going to continue light foliar feeding until my run-off PH increases, or my soil PH increases (which I still need to test). I'll leave a few pics of the plant below. The leaves that were experiencing issues have gotten slightly worse. However, you can tell that the plant is getting nitrogen. It is a bit greener than it was. I am going to have to be careful about that because a couple of leaves are exhibiting clawing (I assume Nitrogen toxicity). Other than that things seem to be okay, but I'm up for further suggestions.