LED Grow Light using Joule Thief Battery Power in a Wick Gardening Container for CHEAP!

So the title has a lot of words in it, but that is because this instructable combines many ideas from many sources. The general idea stemmed from robomaniac's Desktop energy seed lamp combined with }{itch's Growing Plants With LED Lights instructable as well as the many different wick gardening planters that have been posted, but I saw it from whamodyne first (all these ideas are awesome by the way!). I wanted to build an LED grow light that ran off batteries because:

1. I'm a nerd.
2. I wanted citrus plants but I live in an apartment with horrible "sunlight accommodations" in Iowa City, Iowa. Citrus plants require a lot of sunlight and this week alone it's been cloudy almost every day.
3. I live in a college town so anything left outside either gets stolen, broken or thrown up on so growing them inside is a must.

Those are my reasons, maybe you have a few of your own but before going any further I must say that if you're going to use this information to grow pot I will not be held responsible for your drug habits if you are caught. Like I said, I'm using this to start up my lemon, grapefruit and orange seedlings, which last time I checked was perfectly legal.

Referenced instructables:
http://www.instructables.com/id/Table_top_energy_seed/
http://www.instructables.com/id/Growing-Plants-With-LED-Lights/
http://www.instructables.com/id/Self-Watering-Plant-Container-out-of-a-2-liter-bot/

Oh and one of the battery terminals I used came from the design by xtank5:
http://www.instructables.com/id/Battery-Holder-Version-2/
thanks for that idea too!

Step 1 Materials

What you will need are these items, you can improvise if you have similar ones (that's what instructables is pretty much all about) but if you have electrical questions about the resistors or transistors please don't expect too much from me. I have a degree in evolutionary biology, not electrical engineering so hopefully if there are questions about the electrical aspects the group (or the people I referenced) will be able to help out. Anyway, here was the list of what I used:

Materials:
25 x red LEDs (cheap ones off ebay, **see bottom for important details**)
5 x blue LEDs (same)
2 x ferrite beads
2 x 1K resistors
2 x 2N3904 transistors
28 gauge wire and some much thicker scrap wire that was lying around (the thicker wire is not necessary)
1 x perf board

Common materials:
1 or 2 Liter bottle
A gatorade bottle
electrical and clear tape
aluminum foil
pill bottle
cardboard
batteries

Tools:
Soldering iron and solder
Wire stripper (was helpful)
Knife or razor blade
Brain (also helpful)

**LED Info: According to Wikipedia, chlorophyll a & b absorb light at maxima of:
430nm & 662 nm for chlorophyll a
453nm & 642 nm for cholorphyll b
So make sure that you find blue (440490 nm) and red (~625-740 nm) LEDs that are as close to those maxima as possible!
Also, you will notice that there are many more red LEDs than blue ones, this is because I read that red LEDs are more important for flowering than blue LEDs (I was corrected, blue is for growth and red is for flowering) and many people are completely successful with red LEDs alone. Whatever you do, don't waste your money on green LEDs because that wavelength is not absorbed!

Comments

[arnookie]

If you are thinking of building a diy grow light please take note of this.
Each and every led needs to be atleast 1watt each. Anything below that will be useless so don't use old leds out of toys or old boards, they simply will have too little Total lumens versus lumens per watt. You need atleast 10mm LEDs with 1watt per LED to supply enough light to the plant anything lower will not work. A good combination is a pannel made from 75% 1watt red high brightness leds, 20% 1watt blue high brightness leds and 5% 1watt amber high brightness leds. somewhere in the region of 660nm for red and 460nm for blue
There is also no effective difference in penetrative power for horticultural purposes between a 1W LED and a 3W LED. So anything over 1watt is just wasted. This means brightness has very little to do with the benefit you will get once you use 1wat leds. Don't confuse this with a pannel made from say 20 LEDs rated a 10watt as to one with 10 LEDs rated at 10watt. As the 20 watt pannel will use the useless 0.5watt leds verses the 10watt pannel that uses 10x10watt 1watt LEDs that are ideal. This has been tested and proven that 1watt single LEDs have great benefit to plants and anything less is just a waste of time and has no benefit at all to plants. The same applies with going brighter than 1watt has no benefit either.
Hope that may help some of you. Especially if you are growing indoors.
Also LEDs are more efficient than any other form of grow lighting available.
The commercially available LED growlights outperform all other growlamps from HID lamps to including high pressure sodium (HPS) and metal halide (MH) lamps.
So prepare to see other grow lamps become obsolete as LED growlight take over.

[osironi]

@Arnookie. What is the frequency for the amber one (the small 5%) ?

[acmefixer]

The transistor acts like a switch, and turns the current on and off rapidly, which creates spikes of voltage across the coil. The spikes are higher than the 1.5 volts, high enough to cause the LED to conduct current and to put out a pulse of light with every spike. The spikes are much too fast for the eye to see, so the light looks like it is continuous. I recommend using a better transistor than the 2N3904, preferably the 2N4401, MPS2222, or BC337, which gives the highest LED brightness. You can buy these parts on Ebay.

[dexknows86]

i also notice that you dont have any UV leds.. you might be locking out some chemical process' that are vutal to the plants growth.. just food for thought. nice design though.. props

[dexknows86]

i notice that the larger sapling has a bit of leaf curling. i believe that is due to over watering. i see your self watering system and it looks good but i think you need to make your cloth smaller or take one out. it alos could be due to salts building in your soil.

[andybuda]

dose the uses of a transister make the led any brighter....
or isit just to regulate

[andybuda]

i grow some plant useing red (well sodium buld)
and my made grew  plants useing blue (metal halide)
i got very fat leaves
he got more growth but very spindly leaves
so nxt time il do blue for growth and red for flowering
or just use white
you can use coloured plastic but it absorbs to much light for what its worth
low cost energy efficient bulbs you can get flood light versions but they cost about x10 more then the standard just use 3 or 4 of thr cheep 1`s
aparently you need 10 x 11 watt for good growth i think it depends on the size of grow area

[ProphesyOfWolf]

If I wanted to use 85 reds and 15 blues (for a bigger board) how many batteries would I need? Would I need any different parts than what you have listed?

[Durtyoleman]

Am I correct in assuming that there is one each of the resistors and transistors for each sequential string of lights? It is not clear from the diagram or pics but since only two of each were purchaced this would seem to be the case.

[ralegg]

That is correct, sorry it was not clearer. The red LED circuit has its own resistor and transistor while the blue LEDs have their own separate resistor and transistor for their circuit.

[zoltzerino]

that is not called a breadboard. It is a 'perfboard' (perforated) or a 'matrix board'. Breadboards a re-usable clippy type ones, usually white. ZZZZ

[DebH57]

This is pretty cool Ralegg, here in So Cal I use aluminum foil shiny side up laid at the base of my tomato's to get added sun exposure to the vines, I wonder if the same would hold true to give a little extra kick to your grow light? 5

[teslafan100]

very cool

[cheeto4493]

Once you take the lemon seeds out of the lemon, you could use the lemon to make a battery, http://www.instructables.com/id/Lemon-Battery/
Then it would be a renewable energy - LED Grow Light using Joule Thief Battery Power in a Wick Gardening Container for CHEAP!

If you can make it into perpetual energy machine you'll really have something ;-)

[ralegg]

Haha, yes I have thought about what it would be like mixing this with the supercharged lemon Instructable

[Drillbit]

Blue is for growing, red is for flowering.. Also remember Wikipedia is not expected anywhere as factual information for research.. I like the idea allot, but wouldn't you need to be checking all the time to make sure your battery hasn't given out.

[ralegg]

Just as a test, the 3 batteries that were hooked up to the 25 red LEDs had already gone through MANY rigorous hours of use in xbox 360 controllers and they lasted for almost a full 48 hours until they started to dim. So if you were to use this with new batteries, I think that you could get a lot more time out of them, I will be testing them with full batteries soon.

Thanks for clearing that up with the blue for growing and red for flowering.

Also, I know Wikipedia is not a truly scientific source, but I'm lazy and it's a quick find for things. In the end, if someone completely disregarded the wavelengths I placed on here and just bought "red" and "blue" LEDs they would still probably be quite successful with this project. On a side note, here is a link from the University of Hamburg (Germany) that verifies the wavelengths that I wrote earlier.
http://www.biologie.uni-hamburg.de/b-online/e24/3.htm