Is this due to lights being to close or lack of nutes? I’m in 4th week of flower and just feeding it according to Fox farms soil schedule. Temps are about 80 degrees, RH at 48, lights at 12" from canopy with 700-800 PPFD(80%), and pH around 6.2. I spoke to another growmie at a local shop and he stated they are hungry and feed it more cal mag and Big Bloom.
Is that the pH going in or the runoff pH? What soil are you using?
Are you feeding the FF Trio? If so you are likely to have a salt buildup at this point submarining your runoff pH. If runoff is low, then a flush will correct the issue.
Cal/mag is often cited, but is rarely a real issue, particularly if you are already feeding a cal/mag product. Big Bloom contains only micronutrients such as iron, boron, manganese, sulfur, etc… I see no evidence of any micronutrient deficiencies. I expect that you have a root zone pH problem given you are in flowering and using the FF Trio.
I would get a second opinion on whatever they might say going forward. We see quite a bit of advice that isn’t helpful from grow shop employees. That seems to be the case here.
If you can feel the heat from your light on the back of your hand when held at the canopy level, then the light is too close. ~800 PPFD isn’t all that high. I run my plants at 1,100 PPFD without problems.
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I’m using the fox farm trio in addition to Bembe which is recommended on 4th week of flower, soil is FFOF. The pH is 6.2 going in. I have their sledgehammer product for flushing
What is your runoff pH? It is the metric that matters, particularly when using the Trio, which will submarine your runoff pH at this stage. The runoff pH is likely low and is therefore creating nutrient uptake issues.
If pH is the problem, then OF will revert to a runoff pH of ~6.5 with a good flush down to 300 PPM.
I just fed it yesterday can I flush it out now or do I have to wait till next feeding to flush with pH balanced water. Just worried if it will be salvageable or not if I wait till next feed.
It should be fine with some care.
You can flush at any time. Flush it down to a runoff PPM of ~300, give it a light feeding immediately after, then resume normal watering and feeding once the soil has dried out again.
I suggest ditching the Trio, as it is what causes pH problems. Jack’s 321 is a good option that won’t require flushes. I would follow with the FF recommended flushing schedule if you do choose to continue with the Trio.
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Yeah I was thinking of trying something new, a friend of mine gave the micro grow bloom from advanced nutrients, also thinking of trying Athena. I’m going to flush it now with light nutes and let it dry out until next feeding. I’ll check out Jacks, thanks for the assist and recommendation.
I found out the issue. It seems my pH meter was off by +2 so when I was feeding it thinking it was around 6.4. I confirmed this by testing vinegar and it showed a pH of 0 which should of been 2.5-3ph. so I bought another meter which confirms my issue.
What are you using for a pH meter?
I was using viviosun but got the ac infinity meter that came with two calibration liquids 7 and 4. I tested different liquids and came out accurate or close to