LED growbox?

Hey all,

As you might have noticed, I live in Alaska, where around this time of year it's dark a LOT.

So, this got me to thinking. I love growing plants - my habanero plant made over 250 peppers this year alone! But I have buying "gro-lamps" that sometimes work and sometimes don't.

So! Now that I'm immersed in LED-Land (Thanks, CPF...), I got to thinking about building my own LED growbox from Luxeon Stars.

Now, plants absorb light (via Chlorophyll-A) most at around 430nm (+/- 20nm) blue and 662nm (+/-20nm) red. I admit to a highly cursory search but I can't seem to find the wavelengths emitted by the red and blue Lux3s...can anyone help?

I would probably do some kind of experiment - an opaque box with just Lux3s providing light, and a transparent box that "augments" the meager sunlight available now with Lux3s, just to see which one does better.

And before you ask, I'm growing another habanero, a Thai pepper, and two kinds of dwarf tomato.

From the datasheets at Lumileds;

Blue 460-490nm
red 620.5-645.0nm
royal blue 440-460nm
others available on the datasheet link

What type of habeneros are you growing?

I would be interested in some seeds if it is not just your standard habenero.

Sable said:

As you might have noticed, I live in Alaska, where around this time of year it's dark a LOT.

But I have (was that ``hate''?) buying "gro-lamps" that sometimes work and sometimes don't.

Click to expand...

I lived in Fairbanks for some years, and used to sell vegetables at the farmers market. I would always start my basil and tomatoes in February, under cheap shoplights. I would hang them right over the plants, close enough that the top leaves were almost touching the tubes. I hung foil along the sides, so all the light was reflected back to the leaves. They never got spindly, even though they didn't get any sunlight until they were planted out in late May.

The University extension service ran experiments which showed that the cool white flourescents in the cheap shop lights worked at least as well as any flourescent bulbs, including the fancy, expensive growlights.

If you do make an LED grow box, please make it the size of a shop light (in area, not shape, of course) so you can make a meaningful comparison to the cheapie shoplight solution. The blue and red Luxeon LEDs would have to be much more efficiently absorbed by the plants to justify the extra electricity for the same lux, and the extra capital expense.

Let us know how it works out.

Nels

There are several LED "grow lights" on the market. Seems the main appeal is the reduced electricity usage so the local utility company won't snitch the growers off the the local Narcs.

The light setups are still fairly expensive as they haven't hit the mainstream market yet.

nelstomlinson said:

The University extension service ran experiments which showed that the cool white flourescents in the cheap shop lights worked at least as well as any flourescent bulbs, including the fancy, expensive growlights.

Click to expand...

I used to have a terrarium for my carnivorous plants when I lived in Illinois (no longer needed in CA ), and I always used a mixture of cool white tubes and cheap (purplish) plant tubes. Some of the "full spectrum" tubes for sale at the pet store cost $20 each! But I had four 40" tubes, and it's basically common knowledge among experienced plant growers (terrarium or aquatic) that quantity of light matters far more than the spectrum.

Hm. My habanero died last year under around 300w (incan equivalent) of "compact flourescent" lights at work, but maybe there were other considerations that I didn't take into account.

Nitroz, I do have a few chocolate habanero seeds (which I'm saving for myself, sorry!) but if those grow and the plant makes fruit I'll be happy to send some seeds along in a few months when it matures. PM me and I'll remember (probably!). The plant I'm growing right now is a "plain" orange habanero, but holy Jebus it's a burner.

I have noticed there are LED grow lights on the market, but they seem to be clusters of 3mm and 5mm LEDS (likely at the right spectrum, though) for hundreds of dollars for the "good" ones. Being reasonably handy I thought I could do better than that myself, so it's off to LED DIY!

I agree that a making the light with the area of a shop lamp would be best for a meaningful comparison. Now just to figure out how many LEDs I'm going to need to make the same lumens...then how to drive them!

Have a look at http://www.roithner-laser.com/. They sell high power LEDs in the specific wavelengths you need.

For the blue part, a royal blue luxeon would be excellent. For the red part you'll have to look for high power GaAlAs LEDs (660nm) at roithner.

I don't know about LEDs, but I started my peppers off under a shop light - which was good enough until they were ready to transfer to a window ledge, and then outside, under plastic.

I know there are aquarium lights to promote plant growth, rather than just the regular lights that highlight the fish, but I heard that any old shop light would be just as good for growing seedlings.