February 15, 2010 by gisette
Test 3: Greens, is a re-run of Test 1: Greens, whose results were pooched by an LED lamp hardware failure.
Conditions same as Test 1, with somewhat different crops. And a working LED lamp. 
Lights:
16 hours/day.
- 16W triband LED spotlight, 3rd generation (132 red - 18 blue - 18 full spectrum white LEDs, about 7:1:1)
- 15W 6500 K CFL floodlight, 650 lumens, "daylight" bulb with built-in reflector.
For comparison, AG Deluxe bulbs are 26W, but unfocused. They also seem yellower to my eye.
The CFL is definitely hotter. Which probably gives the CFL plants a head start.
2009-02-14: Presoaked 3-4 hours and planted seeds in each of two pots:
Same as in Test 1: Greens:
- 4 French blush radish (thin to 2) - harvest time 25 days
- 3 little Caesar romaine (thin to 1) - harvest 45-60 days
Differ from Test 1: Greens
- 4 toy choi pak choi (thin to 2) - harvest 30 days
- 3 bright lights Swiss chard (thin to 1) - harvest 60 days, but can eat as baby greens
Hypothesis: My best guess :
- There is enough light to grow all 4 species.
- There will be < 10% difference in harvest.
What I want is > 10% difference in harvest - LEDs clearly more grow power for same watts.
Germination:
day 1: CFL side first lettuce already up.
day 2: Doubting that was lettuce yesterday. New two lettuce and two toy choi CFL side, two toy choi and one lettuce LED side.
day 4: At least one up of everything except LED side chard.
Progress:
week 1:
week 2: experiment terminated, answer is clear.
But terminated the experiment. Complete 2 week yield:
Sun, 02/28/2010 - 15:03
#2
week 2: experiment terminated, answer is clear.
But terminated the experiment. Complete 2 week yield:
Yes, by the 3 or 4 week point, I would have gotten more harvest on the LED side than I did with the failed LED lamp. But - not a chance that it would have matched the CFL side yield.
No point wasting any more electricity on this - would rather reuse the space, lights, and pots.
It's only another couple days to the week 2 pictures - no point in a preview. Week 1 pix above. By almost-week-two, the LED side radishes are falling down again.
Bottom line - not substantially different than Test 1: Greens. The LED side should do better this time around, especially in the final week, but the qualitative result will be the same. This (definitely special) CFL grows much better per watt, especially with greens.
I'll certainly let this run until the week 2 point. But beyond that - I don't see much point. The writing's on the wall.