PPFD for Autos?

[MrAutoGrower]

What do you guys run on veg and bloom?

Right now my PPFD has been around 800+ in flower and I’ve noticed some calmag looking def, but it is also linked with light burn.

I’ve raised the light and will give a small dose of calmag just in case. But thinking around 800+ for 18hrs a day is a bit much.

What you think?

 

[Qbgrower]

What do you guys run on veg and bloom?

Right now my PPFD has been around 800+ in flower and I’ve noticed some calmag looking def, but it is also linked with light burn.

I’ve raised the light and will give a small dose of calmag just in case. But thinking around 800+ for 18hrs a day is a bit much.

What you think?

That's around 52 DLI which is fine but you need to make sure everything else is good too. Enough water, nutrients, temperature, humidity etc.

Here's a DLI calculator https://happyhydrofarm.com/plant-dli-chart/#plant-dli-chart

Qb

 

[GreenBean]

600-800 in veg. 800-1000 in bloom. Tweak from/around there if I see that they are responding well, or if they are getting too much = they start to droop a couple hours before lights out.

80F/60RH I try to maintain the entire grow, or somewhere around there. 18/6.

How old/tall are the plants? Is the def at the top of the canopy only? If so, I would try just adding epsom/mag not calmag. YMMV. IMHO. Etc..

 

[MrAutoGrower]

600-800 in veg. 800-1000 in bloom. Tweak from/around there if I see that they are responding well, or if they are getting too much = they start to droop a couple hours before lights out.

80F/60RH I try to maintain the entire grow, or somewhere around there. 18/6.

How old/tall are the plants? Is the def at the top of the canopy only? If so, I would try just adding epsom/mag not calmag. YMMV. IMHO. Etc..

Can you get away with 1000 without co2?

 

[MrAutoGrower]

600-800 in veg. 800-1000 in bloom. Tweak from/around there if I see that they are responding well, or if they are getting too much = they start to droop a couple hours before lights out.

80F/60RH I try to maintain the entire grow, or somewhere around there. 18/6.

How old/tall are the plants? Is the def at the top of the canopy only? If so, I would try just adding epsom/mag not calmag. YMMV. IMHO. Etc..

More so higher up. However my light output was over 1000 in some spots. Some hotspots really. I’ve raised the light up and added in 0.5ml of sensi calmag xtra. I’ll check their response to it tomorrow. Interesting you mentioned the droop, they droop sometimes before lights out.. up to 3hr before the lights go out. Not always but I’ve noticed it sometimes.

I hand feed daily, once a day because I don’t get enough time to squeeze in an extra feed like 6hr later. So they get around 3L (almost a gallon) to run off every day.

Spotting:

 

[GreenBean]

Can you get away with 1000 without co2?

Yeah, I've never had much of a problem with experimenting pushing the PPFD personally. You know me, I am all about experimentation, sort of read about the "science" of things and keep it in mind, but still experiment to find the tipping points.

But it is, of course, plant dependent. For instance, I have that Mango Smile in the tent with the Blackstrap. And parts of the Mango are so tall that they baking under like 1100 PPFD and they don't break a sweat. But the Black Strap is lower and getting around 900-ish PPFD and she has a little foxtail going. But...dunno...if that is a BS thing or not? I'm going to run Black Strap again, with a similarly sized plant in height (I think) so we shall see.

Then, I have had plants like the FB Zkittlez that barely wanted like 500 PPFD before she started getting weird.

I've messed with the CO2 bags and cannisters. I know it's not the same. Never noticed a difference. But again, not the same.

More so higher up. However my light output was over 1000 in some spots. Some hotspots really. I’ve raised the light up and added in 0.5ml of sensi calmag xtra. I’ll check their response to it tomorrow. Interesting you mentioned the droop, they droop sometimes before lights out.. up to 3hr before the lights go out. Not always but I’ve noticed it sometimes.

I've never burned/cooked a plant. But I have had magnesium lockout from adding calmag a few times. Cal will not help anything higher up the plant, it's immobile so it will not do anything for older growth in the way of helping it. But will lockout your magnesium for sure. Rusty spots and tips usually starts at the top in early bloom and can travel down the plant. So I always recommend having some plain espom salts on hand. Mix a teaspoon per gallon with your nutes and water it in. Won't get rid of the spots, but should stop it from spreading. I usually do that a few times and all is good.

I see droop now and then. Interesting thing on this run is that it was the Mango Smile dropping in mid-late veg about 2 hours before lights out. I just dialed back on my dimmer to about 600. But now in full flower, she is just rolling along with high PPFD.

Like yourself, I only feed once a day. About 1 Gallon a day. Sometimes a little more.

 

[MrAutoGrower]

Yeah, I've never had much of a problem with experimenting pushing the PPFD personally. You know me, I am all about experimentation, sort of read about the "science" of things and keep it in mind, but still experiment to find the tipping points.

But it is, of course, plant dependent. For instance, I have that Mango Smile in the tent with the Blackstrap. And parts of the Mango are so tall that they baking under like 1100 PPFD and they don't break a sweat. But the Black Strap is lower and getting around 900-ish PPFD and she has a little foxtail going. But...dunno...if that is a BS thing or not? I'm going to run Black Strap again, with a similarly sized plant in height (I think) so we shall see.

Then, I have had plants like the FB Zkittlez that barely wanted like 500 PPFD before she started getting weird.

I've messed with the CO2 bags and cannisters. I know it's not the same. Never noticed a difference. But again, not the same.



I've never burned/cooked a plant. But I have had magnesium lockout from adding calmag a few times. Cal will not help anything higher up the plant, it's immobile so it will not do anything for older growth in the way of helping it. But will lockout your magnesium for sure. Rusty spots and tips usually starts at the top in early bloom and can travel down the plant. So I always recommend having some plain espom salts on hand. Mix a teaspoon per gallon with your nutes and water it in. Won't get rid of the spots, but should stop it from spreading. I usually do that a few times and all is good.

I see droop now and then. Interesting thing on this run is that it was the Mango Smile dropping in mid-late veg about 2 hours before lights out. I just dialed back on my dimmer to about 600. But now in full flower, she is just rolling along with high PPFD.

Like yourself, I only feed once a day. About 1 Gallon a day. Sometimes a little more.

I do have some red stems going on also. Have done for like a week, so I’ve been keeping an eye out for light issues. Usually red stem is an indicator there’s too much light from what I’ve seen. Don’t know if it’s true until I test that. Thank you for your input bro. I noticed I’m more prone to spotting in flower when I use advanced nutrients grow A and B. Whenever I use advanced nutrients bloom A and B from start to finish I never encounter any issues especially the spotting. I’ve read a few others get it with grow, and they also use bloom instead.

 

[Mañ'O'Green]

Unless you are running HID lamps you do not have light burn from LEDs - PERIOD. I have run Autos with 1500 PPM 60+ DLI and never have any kind of light burn.

What happens with LEDs is that they are so efficient that the plants grow faster than they can get the nutrients they need from your media. This can lead to deficiencies of Mg, Ca, K and P as the plants ramp up the growth of flowers. This is why you should be changing the mix you are feeding the plants going into flower less N more Mg, Ca, P and K. I don't like to foliar feed when the plants are as far along as yours are now. It may have been good a couple of weeks or so ago. Add 50 PPM of Cal-mag and 100 PPM of P and K per gallon to your next fertigation on top of the regular mix you are using. Then drop back to the regular schedule. You are kinda behind the plants needs right now but don't go crazy It doesn't take much to fix what I see.

 

[MrAutoGrower]

Unless you are running HID lamps you do not have light burn from LEDs - PERIOD. I have run Autos with 1500 PPM 60+ DLI and never have any kind of light burn.

What happens with LEDs is that they are so efficient that the plants grow faster than they can get the nutrients they need from your media. This can lead to deficiencies of Mg, Ca, K and P as the plants ramp up the growth of flowers. This is why you should be changing the mix you are feeding the plants going into flower less N more Mg, Ca, P and K. I don't like to foliar feed when the plants are as far along as yours are now. It may have been good a couple of weeks or so ago. Add 50 PPM of Cal-mag and 100 PPM of P and K per gallon to your next fertigation on top of the regular mix you are using. Then drop back to the regular schedule. You are kinda behind the plants needs right now but don't go crazy It doesn't take much to fix what I see.

Yeah I noticed they were drinking pretty fast. I also use sensizym that really helps with nutrient uptake. I checked my run off ppms to see if it was still quite low. Run off has been lower than input by quite a bit lately. Just seems to me like they are demanding more than my usual plants. I’m hoping the calmag issue will be resolved then I’ll ramp the lights up again

 

[CannabisMingus]

Unless you are running HID lamps you do not have light burn from LEDs - PERIOD. I have run Autos with 1500 PPM 60+ DLI and never have any kind of light burn.

I have experienced light burn with LEDs but the top of the bud is almost touching the diodes. I mean - like an inch. Otherwise no issues. I just think we have to exercise caution when we profess an absolute based solely on personal experience, no matter how instructive that experience may be. IMHO, etc.