2.8 watt, 60 bulb white LED

[wordwiz]

I picked a couple of these up for about $9 each - too much to pay as I later found them for about $6 each. But nevertheless, I stuck one over a small tomato plant yesterday morning, a plant that is under a 125 watt R/B/O (8/1/1 ratio) LED. Because it put out very few lumens and no heat, it was 1/4" from the plant. This morning, I moved it up one chain link. This evening, the plant is touching it. I can live with 1/4" -1/2" of growth per day at this stage of growth, especially since the tomato is a determinate and even more so if the internode length stays short.

Just trying to find the most efficient lighting to raise maters indoors!

Mike

 

[Josh]

How many different types of lights do you have going? Your eventual goal is to raise plants indoors to maturity, correct? I will be curious to see if a combination of different lights even possibly for different stages might turn out to give you the most bang for your buck. I am just thinking out loud though. I have no scientific or anecdotal evidence to support that.

 

[wordwiz]

Josh,

I don't have a clue either so don't feel bad! I have found out that CFL lights are perhaps the best bang for the buck for mature basil plants - nothing I have tested comes close. For growing a 7-pod, it will be hard to beat the 125-watt R/B/O LED unless one wants fast growth. The seed was sowed on December 26, probably germinated within a 10 days, grew slowly and was transplanted into the 7-gallon pot about six weeks ago. It is still only about eight inches tall (suffered a major set-back when my plant kitty decided she had to taste the leaves) but it looks great. The goal for this plant is to have lots of pods that I can harvest seeds from.

With the tomatoes, it is a different story. I figure I should get about 2 pounds of ripe tomatoes per plant per week. If I have 60 plants, that's 120 pounds per week. If I sell them for $1.25/lb., that's $150 per week. Over an eight week harvest period, that's $1200, but it will take 16 weeks or so to raise those plants. That means I need to keep my electricity costs down to about $30 per week or 50¢ per plant (not including the outlay for lights and fixtures).

OK, now here I'm getting anal, but in doing the math, I can get six plants under each 125 watt light (1250 watts per hour) plus, if this works out, one 3 watt light per plant (180 watts per hour) for a total of less than 1500 watts per hour. At 12 hours per day, that amounts to $1.80/day or $12.50 per week! Sixteen weeks at $12.50 each week = $200. That would mean a $1000 profit over four months, not that great. But... if I can go from growing 60 to 600 plants, that translates to $2500/month. Then 6000 plants....

I can dream!

Mike

 

[teh purple penguins]

Josh,

For growing a 7-pod, it will be hard to beat the 125-watt R/B/O LED unless one wants fast growth.

Mike

that would be something interesting to figure out there mike, i love the sit back and relax get a great plant method always what i try and do, but what if we wanted it to go faster, do you think that a combination of the LED lights and an HPS or something would speed things up or just not make the great plant the LED's would make? i've seen the pics of your internodal length and overall awesomeness of your chiles grown under the LEDs and they look perfect.

the slow good growth is why i usually use flouros for seedlings and teenagers, how much better did you figure the LEDs were than the flouros for the chiles?

 

[wordwiz]

IME, at least so far, the most economical/efficient light for seedlings seems to be the CFL bulbs, specifically the 23-watt, 5000K ones. Each one is good for about a square foot. They do not grow quite as nice plants as the LEDs but at $2 per foot, the sacrifice in better plants is worth it. However, they are not powerful enough for mature plants, unless I wanted to build an array of them!

I also had great success in growing a tomato to medium size with a 105-watt CFL. The foliage was thick, the internodes tight, the leaves very green. But once it got to about 15" tall, I ran out of light, so to say. I suspect that had I had four of them the plant would have kept growing, bloom and set fruit.

I liked the 400 watt HPS also. Tomatoes did grow and produce fruit decently. But they require a lot of electricity, especially if I look at growing 60 plants - I had six under the one lamp.

So far, the 125-watt LED has done as good as the HPS though not as quickly. It covers about the same amount of area as the HPS and the panel (which I got a sweetheart deal on) was less expensive than the HPS. Plants do not seem to grow quite as quickly but that isn't really a concern - I just need to start them earlier. Plus, going back to 60 plants, I would use 1000 watts of power vs. at least 3200 for the HPS.

Mike