Led harvest

eighties

Member
Watts/sf seems to be not a very good metric for led's IMO. If I figure my 4x6 flower area and divide that by the total wattage at 520 wall watts that only gives me 21.6 w/sf.
Agreed. If we're talking about different types of lights the wattages get confusing. The blurple mfrs make it worse with their "equivalent" or "replaces" wattage. We all know that is crap. In any case, I was just talking about the high quality, full-spectrum lights. In other words, Samsung LM561c, LM301b, or some equivalent diodes. When you're talking about the same diodes a wattage/sf does make a decent proxy for PAR levels.

It's common opinion from a lot of growers that 30w/sf of good LED or 50w/sf of HPS or blurples is a good rule of thumb for flowering, but maybe that is high. You seem to be getting real good results, and, if you're pulling 520w at the wall, you're probably only getting about 475 watts at the boards depending on your driver efficiency. That's only about 20w/sf. Good for you. Your system must be dialed in tight. I do wonder if a bit more light would push things over the top for you, though. With the LED prices having fallen like they have it might be worth a try. If your yield doesn't increase save the electricity. Alternatively, your yield may not increase, but you may be able to shave some time off the veg cycle which would result in an electricity savings.

Food for thought. Happy growing.
 

jarvild

Well-Known Member
Agreed. If we're talking about different types of lights the wattages get confusing. The blurple mfrs make it worse with their "equivalent" or "replaces" wattage. We all know that is crap. In any case, I was just talking about the high quality, full-spectrum lights. In other words, Samsung LM561c, LM301b, or some equivalent diodes. When you're talking about the same diodes a wattage/sf does make a decent proxy for PAR levels.

It's common opinion from a lot of growers that 30w/sf of good LED or 50w/sf of HPS or blurples is a good rule of thumb for flowering, but maybe that is high. You seem to be getting real good results, and, if you're pulling 520w at the wall, you're probably only getting about 475 watts at the boards depending on your driver efficiency. That's only about 20w/sf. Good for you. Your system must be dialed in tight. I do wonder if a bit more light would push things over the top for you, though. With the LED prices having fallen like they have it might be worth a try. If your yield doesn't increase save the electricity. Alternatively, your yield may not increase, but you may be able to shave some time off the veg cycle which would result in an electricity savings.

Food for thought. Happy growing.
My veg times from rooted cuttings is only 21-25 days.
Another poor comparison is grams per watt. If I use that metric I'm steady at 1.9-2.1 gpw with my setup now.
 

eighties

Member
My veg times from rooted cuttings is only 21-25 days.
Another poor comparison is grams per watt. If I use that metric I'm steady at 1.9-2.1 gpw with my setup now.
I don't see what's wrong with gpw as a metric except that it doesn't take into account time. Maybe we should be figuring grams per kilowatt hour which would lead right into a cost/gram. We need some way to keep track of how we're doing. Also, 1.9-2.1gpw is really good. It's at the high end of what I see good growers putting out from DWC systems.
 

jarvild

Well-Known Member
You are vegging for 21 days and hitting almost 2 per 600 watts of LED?
We will see the results in 2 weeks or so, they come down next Sunday :cool::weed:. I may not quite make it this time as I pulled 3 plants and put them under the HPS midway through flower as I needed to space my fixtures out more.
Just my routine, been doing it for years. 9 Lt pots of coir, single daily metered feeds, nutrient levels between 400-600 ppm (.5 conversion), 21-25 days veg with my hardiest cultivars nets me 2 1/2 to 3 1/2 ounces per plant no matter whether under HPS or LED's, only difference is the wattage used to hit those numbers and the plants seem to finish faster under the LED's.
Comparison and up-date photos will up-load this evening.
 

jarvild

Well-Known Member
Post # 15 was 6 plants under 270 watts and produced 18 dried ounces. This round 9 plants under 520 watts, so I may not make the 2 unit goal.
 

a mongo frog

Well-Known Member
sounds doable if its from good clones
Show us what you mean. If you could show us a 21 day vegged plant. Like what do you do top at day 7 or 10 again at day 14 or 16 or just topped once or? Give us an idea. Show us some dried bud shots while you're at it please. We want to learn!!!!
 

coreywebster

Well-Known Member
Post # 15 was 6 plants under 270 watts and produced 18 dried ounces. This round 9 plants under 520 watts, so I may not make the 2 unit goal.
Cool, was been too lazy to look back through the posts..
Figured you must be running 9 or something with 21 days veg.
 

eyderbuddy

Well-Known Member
Show us what you mean. If you could show us a 21 day vegged plant. Like what do you do top at day 7 or 10 again at day 14 or 16 or just topped once or? Give us an idea. Show us some dried bud shots while you're at it please. We want to learn!!!!
how many plants @jarvild ?
coreywebster has the right idea. The more plants you have, the faster you can fill out the scrog space and flip
 
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