Hello,
Wondering if anyone has any thoughts on the attached pictures? The first four images are showing some yellowing on new growth for one of my four plants. Particularly at the tips, with some having very distinct regions of yellow/lighter green, as is evident in image 3. Maybe five of these leaves have begun to form small brown, rust like spots at their edges and tips (apologies for the lack of camera focus), as can be seen in image 2. This one plant has been a beast relative to the others, remaining a good 1-1.5 weeks ahead of the others in terms of relative growth (even though it has had the same feed). Some of the newer leaves of the other three plants have minor light yellow tips (see foreground leaves in image 5), but nothing to the extent of the other plant.
Throughout the grow I have also had leaves with a regular light->dark pattern, as is evident on the leaves in the center of image 5, relative to those to the left of the image, which have a uniform colour. Some of these leaves, particularly towards the base of the plant have developed brown tips and edges. As this is my first grow, I took this to be nut burn and reigned in my feeding schedule (detailed in the questionnaire below). But only recently have I realized that this 'burn' only appears on leaves with the pattern shown in image 5, and therefore might be a deficiency?
Any thoughts would be appreciated.
Thanks.
How long has this problem been going on? 2 weeks.
What system are you running? DTW.
What STRAIN are you growing? White Widow and Northern Lights.
What was the establishing technique? FemSeeds
What is the age of your plants? Approx 8 weeks from sprouting.
How long have they been in there mixture they are in now? Started in Solo cups, transplanted to 7Lt (1.8 gal) pots after 3 weeks.
How tall are the plants? 22 to 26"
What PHASE are the plants in? Veg, about to flip to flower.
What substrate/medium are you using?(Hydroton, RockWool etc.) Canna CoCo with 25% perlite. Approx 1/2" Hydroton layer in base of pot and on its surface.
What is the Water temperature? 15-20c maybe.
What color are your roots? White? Brown? Are your roots slimy? Roots coming out drainage holes are white and not slimy.
What Nutrient's are you using?(If growing soiless) Two plants are on Canna Coco light feeding schedule, while the other two are using Head's formula.
How much of each nutrient are you using with how much water? 14L (3.7 gal) between 4 plants gives me 30% runoff. After the plants became situated I was using 2/3 Head's on two plants (~500ppm on Truncheon TDS 500 scale), and 2/3 Canna Light feeding schedule on the other two plants (~400ppm), for approx one month.
But began to see what I thought was nut burn and brought everything down to 1/2 Head's(~400ppm)/Canna(~350ppm) throughout December (though I now think what I was/am seeing is a deficiency rather than burn). I'm now feeding full strength Head's and Canna light schedule (700ppm and 550ppm respectively).
How often are you feeding? I water once every day.
How often are you giving nutrients? With every water.
What order are you mixing your nutrients? For Head's formula, Micro followed by Bloom. For Canna, it's A+B, then Rizo, then Cannazym.
What is the TDS/EC/PPM you are using As above
What is the pH of the "Tank"? pH to 5.8
How often are you testing your pH/PPM/EC/TDS? Every water.
Are you sure your calibration is correct on your equipment? I keep them calibrated.
When was your last watering? 20 hours ago.
When was your last feeding change? (ie. grow-bloom-micro-additional) Given that what I am seeing looks like it might be a deficiency, and the plant with the most severe signs is the one that's grown the most, I have been increasing my nutes from 1/2 the recommend strength to full strength over the past week. (1/2 to 2/3 to 3/4 to full).
What size bulb are you using? I'm using my own custom made LED CoB array ~300W.
What is the distance to the canopy? Distance varies, but the tallest is ~ 12" from the light. Heat density is low with 64 Cobs across an area ~1m^2 (9^2 feet), each using about ~4.5W. They are well heatsinked and unless your 1" away from the emitter you can't feel any heat. I might consider that the yellowing could be from too much light, but it is just as apparent on new growth further away from the light as it is on leaves that are the closest.
What is your RH Factor(Relative Humidity)? Humidity has been a little on the high side. Where bud sites will form it's around 70% on avg, while 80-85% at the floor of the tent. I'll have a dehumidifier set up before flowers start to develop.
What is the canopy temperature? 21-25C (70 -77f)
What is the Day/Night Temp? (Include flucutaion range) As above
What is the current Air Flow? (cfm etc.) maybe 250-300cmf. I'm using a 200mm Hyperfan at 35%, rated for max 710cmf @ 100%.
Tell us about your ventilation, intake exhaust and when its running and not running ? Exhaust is though a carbon filter, and I never turn it off. Intake is through the tents inbuilt intake holes, x2 ~200mm diameter meshed holes with circular inserts on either side to redirect light.
Is the fan blowing directly at plants? Yes, I have a 400mm (~16") wall mount reciprocating fan on High blowing from above. This also never stops.
Is your water HARD or SOFT? Very soft, truncheon reads lowest possible value. With individual ion ppm's around the single digits.
What water are you using? Reverse Osmosis (RO)? Tap? Tap. I don't bother to dechlorinate.Are you using water from a water softener? No
Has plant been recently pruned, cloned off of or pinched. I trimmed excess leaves from the base of the plants to aid in watering. This would have happened around approx 2 weeks ago. So may have something to do with it.
Have any pest chemicals been used? If so, What and When?
Are plant's infected with pest's No. I see no sign of pests.
Wondering if anyone has any thoughts on the attached pictures? The first four images are showing some yellowing on new growth for one of my four plants. Particularly at the tips, with some having very distinct regions of yellow/lighter green, as is evident in image 3. Maybe five of these leaves have begun to form small brown, rust like spots at their edges and tips (apologies for the lack of camera focus), as can be seen in image 2. This one plant has been a beast relative to the others, remaining a good 1-1.5 weeks ahead of the others in terms of relative growth (even though it has had the same feed). Some of the newer leaves of the other three plants have minor light yellow tips (see foreground leaves in image 5), but nothing to the extent of the other plant.
Throughout the grow I have also had leaves with a regular light->dark pattern, as is evident on the leaves in the center of image 5, relative to those to the left of the image, which have a uniform colour. Some of these leaves, particularly towards the base of the plant have developed brown tips and edges. As this is my first grow, I took this to be nut burn and reigned in my feeding schedule (detailed in the questionnaire below). But only recently have I realized that this 'burn' only appears on leaves with the pattern shown in image 5, and therefore might be a deficiency?
Any thoughts would be appreciated.
Thanks.
How long has this problem been going on? 2 weeks.
What system are you running? DTW.
What STRAIN are you growing? White Widow and Northern Lights.
What was the establishing technique? FemSeeds
What is the age of your plants? Approx 8 weeks from sprouting.
How long have they been in there mixture they are in now? Started in Solo cups, transplanted to 7Lt (1.8 gal) pots after 3 weeks.
How tall are the plants? 22 to 26"
What PHASE are the plants in? Veg, about to flip to flower.
What substrate/medium are you using?(Hydroton, RockWool etc.) Canna CoCo with 25% perlite. Approx 1/2" Hydroton layer in base of pot and on its surface.
What is the Water temperature? 15-20c maybe.
What color are your roots? White? Brown? Are your roots slimy? Roots coming out drainage holes are white and not slimy.
What Nutrient's are you using?(If growing soiless) Two plants are on Canna Coco light feeding schedule, while the other two are using Head's formula.
How much of each nutrient are you using with how much water? 14L (3.7 gal) between 4 plants gives me 30% runoff. After the plants became situated I was using 2/3 Head's on two plants (~500ppm on Truncheon TDS 500 scale), and 2/3 Canna Light feeding schedule on the other two plants (~400ppm), for approx one month.
But began to see what I thought was nut burn and brought everything down to 1/2 Head's(~400ppm)/Canna(~350ppm) throughout December (though I now think what I was/am seeing is a deficiency rather than burn). I'm now feeding full strength Head's and Canna light schedule (700ppm and 550ppm respectively).
How often are you feeding? I water once every day.
How often are you giving nutrients? With every water.
What order are you mixing your nutrients? For Head's formula, Micro followed by Bloom. For Canna, it's A+B, then Rizo, then Cannazym.
What is the TDS/EC/PPM you are using As above
What is the pH of the "Tank"? pH to 5.8
How often are you testing your pH/PPM/EC/TDS? Every water.
Are you sure your calibration is correct on your equipment? I keep them calibrated.
When was your last watering? 20 hours ago.
When was your last feeding change? (ie. grow-bloom-micro-additional) Given that what I am seeing looks like it might be a deficiency, and the plant with the most severe signs is the one that's grown the most, I have been increasing my nutes from 1/2 the recommend strength to full strength over the past week. (1/2 to 2/3 to 3/4 to full).
What size bulb are you using? I'm using my own custom made LED CoB array ~300W.
What is the distance to the canopy? Distance varies, but the tallest is ~ 12" from the light. Heat density is low with 64 Cobs across an area ~1m^2 (9^2 feet), each using about ~4.5W. They are well heatsinked and unless your 1" away from the emitter you can't feel any heat. I might consider that the yellowing could be from too much light, but it is just as apparent on new growth further away from the light as it is on leaves that are the closest.
What is your RH Factor(Relative Humidity)? Humidity has been a little on the high side. Where bud sites will form it's around 70% on avg, while 80-85% at the floor of the tent. I'll have a dehumidifier set up before flowers start to develop.
What is the canopy temperature? 21-25C (70 -77f)
What is the Day/Night Temp? (Include flucutaion range) As above
What is the current Air Flow? (cfm etc.) maybe 250-300cmf. I'm using a 200mm Hyperfan at 35%, rated for max 710cmf @ 100%.
Tell us about your ventilation, intake exhaust and when its running and not running ? Exhaust is though a carbon filter, and I never turn it off. Intake is through the tents inbuilt intake holes, x2 ~200mm diameter meshed holes with circular inserts on either side to redirect light.
Is the fan blowing directly at plants? Yes, I have a 400mm (~16") wall mount reciprocating fan on High blowing from above. This also never stops.
Is your water HARD or SOFT? Very soft, truncheon reads lowest possible value. With individual ion ppm's around the single digits.
What water are you using? Reverse Osmosis (RO)? Tap? Tap. I don't bother to dechlorinate.Are you using water from a water softener? No
Has plant been recently pruned, cloned off of or pinched. I trimmed excess leaves from the base of the plants to aid in watering. This would have happened around approx 2 weeks ago. So may have something to do with it.
Have any pest chemicals been used? If so, What and When?
Are plant's infected with pest's No. I see no sign of pests.