Hey folks! 
I wanted to ask some more experienced growers about a problem I just discovered recently. On some of my plants, mostly the taller ones, the leaf tips started yellowing a bit and soon began to twist themselves (it pains me just to look at it
).
First, I only noticed it at the top leaves, which is why I thought of light stress, since the symptoms can only start showing after a few weeks of overexposure. Now I also noticed it with lower leaves, with older ones as well as with brand new ones.
I couldn't find any advice on this particular problem, it just says everywhere "yellowing, wilting, browning tips = nute burn", but nothing about this sign explicitly. My personal nightmare is that I'm working unnoticed under a combination of light stress, nute burn, and some deficiencies, etc. pp. (it's my first grow, so I'm trying not to let all the possible mistakes that could be made freak me out, I just don't want to have to throw everything away after getting this far
)
Here are some pictures:
And here are the stats:
5 of 10 plants are showing the signs, all are automatics, roughly 6 - 8 weeks past germination
Grow light is the Lumatek ATS 300W Pro (up to 2.7 µmol/J). It has been running on the full 310 watts for the past few weeks and distance to the tallest canopy was never less than 40 cm (16 in), although Lumatek recommends to hang it as close as 30 cm (12 in) to the canopy during veg and even closer during flowering.
Also, some plants are showing praying leaves, which can mean that lightling is optimal, as long as the plants are healthy. Those are two of the smallest ones though.
Watering every 3-5 days with pH'd water, pH at root zone is around 6.5. After I was a little incautious at first with the fertilizers, giving my autos the recommended doses, I reduced it to less than 1/4 of the recommended dosage since 2 weeks (BioBizz Fish Mix for the younger ones and Crazy Hills Prosper Flowering Mix for the ones that had started flowering, I gave less than 1/4 of the recommended dosage).
I have two fans blowing diagonally across the canopies and an exhaust fan, both running 18-20 hours each day.
Now I have read that the fans could cause the leaves to overtranspire, hence the stomata wanna turn upwards to transpire more. Could be a possibility, since the fans have been blowing directly on some of the plants. I'm not sure though if it might actually be also a sign that I gave them too many nutrients, but I guess they should have shown burn signs earlier then, not almost a month later.
I will be greatful for any input at all, just wanna know what you guys think about it. It all might turn out O.K. in the end, but of course I wanna do what lies within my power to provide the best possible environment for the plants. Would prefer to hang the lights closer again to promote faster growth and flowering, but I really don't wanna burn the darlings.
André
I wanted to ask some more experienced growers about a problem I just discovered recently. On some of my plants, mostly the taller ones, the leaf tips started yellowing a bit and soon began to twist themselves (it pains me just to look at it
).First, I only noticed it at the top leaves, which is why I thought of light stress, since the symptoms can only start showing after a few weeks of overexposure. Now I also noticed it with lower leaves, with older ones as well as with brand new ones.
I couldn't find any advice on this particular problem, it just says everywhere "yellowing, wilting, browning tips = nute burn", but nothing about this sign explicitly. My personal nightmare is that I'm working unnoticed under a combination of light stress, nute burn, and some deficiencies, etc. pp. (it's my first grow, so I'm trying not to let all the possible mistakes that could be made freak me out, I just don't want to have to throw everything away after getting this far
)Here are some pictures:
And here are the stats:
5 of 10 plants are showing the signs, all are automatics, roughly 6 - 8 weeks past germination
Grow light is the Lumatek ATS 300W Pro (up to 2.7 µmol/J). It has been running on the full 310 watts for the past few weeks and distance to the tallest canopy was never less than 40 cm (16 in), although Lumatek recommends to hang it as close as 30 cm (12 in) to the canopy during veg and even closer during flowering.
Also, some plants are showing praying leaves, which can mean that lightling is optimal, as long as the plants are healthy. Those are two of the smallest ones though.
Watering every 3-5 days with pH'd water, pH at root zone is around 6.5. After I was a little incautious at first with the fertilizers, giving my autos the recommended doses, I reduced it to less than 1/4 of the recommended dosage since 2 weeks (BioBizz Fish Mix for the younger ones and Crazy Hills Prosper Flowering Mix for the ones that had started flowering, I gave less than 1/4 of the recommended dosage).
I have two fans blowing diagonally across the canopies and an exhaust fan, both running 18-20 hours each day.
Now I have read that the fans could cause the leaves to overtranspire, hence the stomata wanna turn upwards to transpire more. Could be a possibility, since the fans have been blowing directly on some of the plants. I'm not sure though if it might actually be also a sign that I gave them too many nutrients, but I guess they should have shown burn signs earlier then, not almost a month later.
I will be greatful for any input at all, just wanna know what you guys think about it. It all might turn out O.K. in the end, but of course I wanna do what lies within my power to provide the best possible environment for the plants. Would prefer to hang the lights closer again to promote faster growth and flowering, but I really don't wanna burn the darlings.
André
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