I have one major problem last year with growing seedlings, running out of space. I grow many different types of plants with various germination/growth rates and varied start dates. This forces me to make sacrifices for placement of my movable light and eventually forced to move some plants outside earlier than I should. The light needs to be close to the newly emerging seedlings, but can’t be burning the more mature plants growing into it. My solution to this problem is a LED storage container grow box. With this I will have a portable seeding area and since LEDs practically emit no heat the plants can literally touch the lights without problems. At that time I move them to a larger grow box where it can continue to grow and start more seedlings. I thought about creating my own LED matrix and buy individual LEDs and solder them together, but that sounded like a lot of tedious work and soldering, which I most likely would mess up. Given it was after Christmas and LED lights were really cheap, this seemed like a good possible solution.
Materials cheap grow box with LED lights:
- 3 gallon Rubbermaid tub
- 1 string white or blue LED Christmas lights (50% off after Christmas)
- Drill with (1/4 in drill bit)
- Hot glue gun (may be optional)
Take a look at the number of lights on your string (mine had 60) then by measuring your tub figure out how you want to create your matrix. Best to double check your measurements as you can see below I miscounted and only planned out 55 holes which I improvised and added 5 more after the fact. You can also combine multiple strings if you want, given the low wattage you can string dozens of these together if you really wanted.
Drill holes that will provide tight friction fit to the tub, for my lights this was 1/4 inch drill bit but for yours this may be more or less, I would recommend starting smaller and increase until you find just the right fit. Once you have all your holes drilled fit each of the LEDs into the holes you drilled some of the connections between the bulbs will have a solid section in between (resistor) so depending on the spacing might be best to make this one diagonal of the previous light to make it not as tight a fit. If you have some lights that just won’t stay in, apply a small dab of hot glue between the bulb and the lid. This may diffuse the light a little but very little intensity at the base so light loss should be minimal.
Last plug it in and check out your cheap LED light. You may want to shake it upside a couple times and find any loose lights while your glue gun is still hot.
Now some of your might be thinking (including myself) are these lights intense enough to allow adequate vegetative growth? I did take a look at the LED matrix with my homemade spectrograph and it did show a high intensity of blue wavelength with minimal on red and orange/yellow/green so for this small space it may just work. I am going to test it out on some guinea pig plants now and if I start seeing tall spindly growth I can easily switch out the current while LEDs with some ultra bright blue LEDs by simply pulling out the socket, swap out old LED (save some other project), replace with new LED, trim excess terminal wire, and push back into the socket. Below is my proof of concept for this as long as the voltage/amperage is the same the circuit will continue to work, below is my proof of concept.
I also purchased a couple of red LED Christmas lights for plant flowering stage but have a couple months before I need to pull those out.
For build cost, this small storage container costs less then $2.00 and with the 50% off sale on Christmas lights at $3.00 I have a cheap grow box with full LED grow lighting for just $5.00 and about 15 minutes of assembly.