In my 4 ft x 4 ft grow space and usimg a 600 Watt blurple LED (true power draw from outlet), i only yielded 5 ounces. I used a DNA Genetics strain called The OG #18, and I grew in coco coir. The plants remained healthy throughout the grow, but the buds never seemed to pack on much weight. The only thing that was not ideal in my grow was the temperature near the root zone, which ranged from 13C (55F) at lights off to 17C during lights on. The temperature near the canopy was from 13C (55F) to 22C (72F). Could the low temperatures cause the low yield I had? What else could cause the low yield if the plants were green and healthy looking the entire grow? I know the blurple lights are not the best but other people seem to get better yields with blurples at even lower wattage than I had. The pictures I attached show a quarter to a half of my 5 ounce disappointment.
Gorillaglue4u
Well-Known Member
Temps are a little cold im sure that played a big part of it. I run my leds lights on around 83 lights off 78ish. However the plant looks great. Maybe it didnt finish all the way?
Hydro4life
Well-Known Member
Yep lower temps wouldnt of helped. How long did you veg for? As far as i know alot of the ogs arent massive yielders.....? Maybe raise temps a bit and get a higher yielding strain with more veg time? 5 ozs from 1 plant isnt all bad or maybe having 3 plants in there could of yielded 3 to 4 ozs a plant? Totalling 9 to 12 ozs??
Thundercat
Well-Known Member
Temps certainly weren't ideal and that can hugely impact results, I've been struggling with the same through this winter its been super cold a few times here.
How high was your light above the canopy, that isn't a ton of light for that much area. You can use training techniques to try to even out the canopy for better light coverage and yield. There are many factors to yield, but the amount of light your plants have to work with is directly related to yield.
Some strains just aren't big yielders.
How high was your light above the canopy, that isn't a ton of light for that much area. You can use training techniques to try to even out the canopy for better light coverage and yield. There are many factors to yield, but the amount of light your plants have to work with is directly related to yield.
Some strains just aren't big yielders.
Grown for years. Just completed a low temp grow for the first time. Lows of 6c at night (air). Nft res kept at 20. Bud growth slowed considerably on one strain. Stopped altogether on another , even after adding emergency heating ( which get one strain going again). Mandala #1 hates the cold that's for sure.
Normal 4x4 yield is around 16oz with arm sized buds. Don't think I managed 4oz this time.
Environment now heated properly.
Normal 4x4 yield is around 16oz with arm sized buds. Don't think I managed 4oz this time.
Environment now heated properly.
The light was about 20 inches above the plants, but I would probably lower it a bit next time. I topped the plants but didn't expect them to stretch by over 200% and I couldn't bend the stems without snapping them once they were stretching. The stems were super hollow and would crack when I tried to supercrop a couple of them (even if I was patient). I will try to even the canopy better next time since I will be prepared for this strain's stretch. Some people claim 0.8-1 gram per watt of power with nice LED lights, so I expected I could get more than the 0.25 grams per watt with a cheaper light. That is why I am wondering if the temperature could have caused a big difference in yield. It isn't a huge yielding strain, but 5 ounces still seems pretty awful for the setup I had.
What type of lights did you get 16oz with and how much power do they draw from the wall? I'm hoping I was just dealing with the cold and I won't have to buy more lights.
I had 4 plants, so each one only yielded about 1 ounce. The OG #18 isn't a huge yielder from what I've read but 1 ounce per plant seems way too low so I feel I must have done something to screw up the yield. DNA Genetics claims it gets about 30% more yield than their other OG Kush. I grew them from seed and switched to 12/12 after 4 weeks or so. They were topped at the third node and were about 25 cm (10 inches) tall at the start of flowering, but they stretched to be about 60 cm tall (24 inches) or maybe a little taller. It made a lot of small buds and no connected colas but I think that is just due to the strain.
400W MH for grow, 600W HPS for flower. (about 620w draw). Standard stuff.
I've got LEDs but they are unusable in the UK cold months (in an outbuilding grow tent). Just not enough heat. I've not done a full LED grow yet. I'm planning on doing one this summer (start in mid June) in my indoor tent (much warmer environment). 2 x Mars Hydro 144 LED jobbies (300 real watts each - spec is 450w - 3w leds).
I use 2 x Mars Hydro full spectrum "300w" leds for early veg (124 real watts) and they work fantastically. One at first , then add the second when the plants grow outside of the light's footprint.
I also have one of those £16 ebay square LED lights - draws about 35 watts. Perfect for cuttings and seedlings
I've got LEDs but they are unusable in the UK cold months (in an outbuilding grow tent). Just not enough heat. I've not done a full LED grow yet. I'm planning on doing one this summer (start in mid June) in my indoor tent (much warmer environment). 2 x Mars Hydro 144 LED jobbies (300 real watts each - spec is 450w - 3w leds).
I use 2 x Mars Hydro full spectrum "300w" leds for early veg (124 real watts) and they work fantastically. One at first , then add the second when the plants grow outside of the light's footprint.
I also have one of those £16 ebay square LED lights - draws about 35 watts. Perfect for cuttings and seedlings
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Below is a crop when the temps are warm, and it never drops much below 15 at night.
Then below, is my cold grow thsi winter, with 3 more weeks flowering too.
Notice on the front plants how the leaves have gone straight up? - (Mandala #1). The rears followed some time later (Bubblegum Pro). The mandala stopped budding and never recovered. Yield is minimal. The Bubblegum recovered but were waaaay under.
Then below, is my cold grow thsi winter, with 3 more weeks flowering too.
Notice on the front plants how the leaves have gone straight up? - (Mandala #1). The rears followed some time later (Bubblegum Pro). The mandala stopped budding and never recovered. Yield is minimal. The Bubblegum recovered but were waaaay under.
Hydro4life
Well-Known Member
Ohhh from 5 plants. 1 oz a plant. Yeah pretty low yield..... And those temps are very low. I run 32 degrees Celsius but that's with 1250 ppm of co2. If I run lower temps with my co2 i dont see big benefits using co2 at 1250ppm. Unfortunately if 1 thing is not optimum you will not get optimum yield. But yes plants look very healthy. And should be an easy fix for more yield next go!!
Hydro4life
Well-Known Member
I've also got a lemon og kush plant 7 weeks into flower. (Half lemon skunk and half og #18.) As far as i know the og #18 is sativa dominant. My lemon og looks to be only half way through flower and seems to be a nearly 100% sativa pheno! I presume this is from the og #18?? Maybe your og #18s were harvested a little early also??
SunPlix CMH
Well-Known Member
The temperature is a little low. Besides heat, what's ppfd and spectrum?
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https://www.sunplix.com/product/led-grow-light/
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https://www.sunplix.com/product/led-grow-light/
coreywebster
Well-Known Member
I bought a 600w true watt blurple a couple of years ago while waiting on parts for my COB build, never did use it but lent it to a mate to try.
The buds were literally tiny , think the spectrum was pretty shit. It broke after one run too so I cant play with it even if I wanted to.
I have never had issues like that with proper COBs, QBs , CMH or HPS.
What exact light were you using?
Yeah your low temps are literally crippling your plants performance. The cheapest option for cold months if your planning another grow would be MH/HPS and a small oil filled radiator at lights out, also making sure your not on a cold floor.
The buds were literally tiny , think the spectrum was pretty shit. It broke after one run too so I cant play with it even if I wanted to.
I have never had issues like that with proper COBs, QBs , CMH or HPS.
What exact light were you using?
Yeah your low temps are literally crippling your plants performance. The cheapest option for cold months if your planning another grow would be MH/HPS and a small oil filled radiator at lights out, also making sure your not on a cold floor.
jjng5
Well-Known Member
Ouch that's 0.23 grams per watt. From your photo's the node length looks crazy long and bud seem very lean. The genetics and pheno of that exact plant IMO is one of your issues. The seed business is big business and very competitive. It's hard to say whether or not that strain is stabilized properly from the breeder or was it just rushed out to market. Many people claim it can take up to 8-9 generations to perfect the lineage of a strain so that it's stable. I would try another strain or another pheno (a different seed from that supplier if you still have some left). I think genetics is a good 40% of the equation myself. Then say 30% for light quality. 10% nutes, 10% air quality and temps, 10% training/cropping. Just my opinion though.
Bottom line that's a pretty rough yield my friend. 0.5 g/watt is benchmark for HID lighting with the target goal of 1 g/watt. For quality LED lights your benchmark should be 1 g/watt with a target goal of up to 2 g/watt. If your blurple light is 600 true watts from the outlet, then that's not a terrible light -- it's not very efficient obviously, but you should be able to at least get around 0.5 to 1g / watt with everything else dialed in IMO.
The other major issue I think you're having is quantity of light. 600 watts of blurple light from one lamp is not enough for a 4x4 space, so you're never going to see very dense buds (except maybe in the very center point of the grow). Additionally a light like that cannot reach 4' out. Get yourself a cheap-o Lux meter on eBay and play around with it in your tent (yes I know, LED is not meant for Lux meters only HID and fluorescent -- but who cares, it will still give you a gauge on light reach and penetration for around $10 verse a PAR meter which is ~$150). To be honest even if that light 600W light was HPS, it would still struggle to have the reach and penetration at the corners of the tent. You should seriously consider adding more lighting to your tent. With lighting it is not only about quantity of light, and quality of light, but also the light foot print. If I were you I would go onto HLG's website they are running their new QB 324 V2 panels for $80 with the sinks! Buy two of those panel/sink combo's and one HLG-320H-C2800 driver and you'll see a huge increase in your yield for $275 investment -- again not just because of the additional wattage added, but also because of the improved footprint of your lighting to your canopy. LED light does not have the kind of footprint and penetration ability to do a whole tent from one single LED lamp IMO (esp. if you're growing sativa plants). That's another reason your plants are so stretched on some of your photo's. They're reaching for light that they're not getting (enough of). This will put you in range to have 57 watts per sq ft total (and since we're counting a blurple light in that) you'll be right where you need to be.
Bottom line that's a pretty rough yield my friend. 0.5 g/watt is benchmark for HID lighting with the target goal of 1 g/watt. For quality LED lights your benchmark should be 1 g/watt with a target goal of up to 2 g/watt. If your blurple light is 600 true watts from the outlet, then that's not a terrible light -- it's not very efficient obviously, but you should be able to at least get around 0.5 to 1g / watt with everything else dialed in IMO.
The other major issue I think you're having is quantity of light. 600 watts of blurple light from one lamp is not enough for a 4x4 space, so you're never going to see very dense buds (except maybe in the very center point of the grow). Additionally a light like that cannot reach 4' out. Get yourself a cheap-o Lux meter on eBay and play around with it in your tent (yes I know, LED is not meant for Lux meters only HID and fluorescent -- but who cares, it will still give you a gauge on light reach and penetration for around $10 verse a PAR meter which is ~$150). To be honest even if that light 600W light was HPS, it would still struggle to have the reach and penetration at the corners of the tent. You should seriously consider adding more lighting to your tent. With lighting it is not only about quantity of light, and quality of light, but also the light foot print. If I were you I would go onto HLG's website they are running their new QB 324 V2 panels for $80 with the sinks! Buy two of those panel/sink combo's and one HLG-320H-C2800 driver and you'll see a huge increase in your yield for $275 investment -- again not just because of the additional wattage added, but also because of the improved footprint of your lighting to your canopy. LED light does not have the kind of footprint and penetration ability to do a whole tent from one single LED lamp IMO (esp. if you're growing sativa plants). That's another reason your plants are so stretched on some of your photo's. They're reaching for light that they're not getting (enough of). This will put you in range to have 57 watts per sq ft total (and since we're counting a blurple light in that) you'll be right where you need to be.
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PURPLEB3RRYKUSH
Well-Known Member
5 ounces for about 200 watt draw of power, little low on the yield but still ok. Max u pull of that light would be around 8, 9 oz
old buzzard
Well-Known Member
how long did you flower for?sorry if you mentioned it(I'm stoned) and I missed.just wondering if they maybe just needed 4 more weeks or so.Thats what it looks like.
Kingrow1
Well-Known Member
Im sure its not the case but it always troubles me when peeps mention high tent temps and assume in a lot of cases the thermometer is in or under the light causing it to register higher than the actual air temperatures.
growingforfun
Well-Known Member
Everyone is saying it's your temps but they arnt THAT low... I've ran colder than That an done just fine.
I'm gonna say its 85% your light, 10% being new, and 5% the temps.
I'm gonna say its 85% your light, 10% being new, and 5% the temps.