LED lights for seedling starts

I have been starting seedlings under flourescents and now wondering if anyone has easy to follow steps for LED line lights.

If I were in your shoes, I would try and use the fluorescent fixtures and convert them to LED to make use of the reflector and use the frame as a basis for the conversion. Replace the fluorescent bulbs and their sockets with a straight piece of metal or wood to support the strips of LED tape. Take out the power supply for the fluorescent bulbs and substitute it for the LED power supply.

The only important considerations I can think of are the following:

  • Make sure you’re using the right light spectrum (or mix of it) for growth (and type of growth: vegetative or flowering)
  • Make sure you have enough lumens/sq.ft. so that your plants aren’t stretching up to the light.
  • Make sure you have enough amperage available, but you should since you’ll be using about half the wattage you previously did (which I assume is the whole point of the conversion).

“Sounds like a good idea to use the housing and change the lights - how do I find out about right light spectrum and lumes/sq.ft?

For light intensity (I know I said lumens, but that’s not a useful unit of measure), I believe the rule of thumb is 32 watts per square foot of growing space (and far enough away to not burn/desiccate the plants). Everyone often says low-intensity lighting (LED/fluorescent) should be 10-12 inches away for the plants, but in my own experience I have them much closer than that (about 2 inches) which works better in my experience (less stretching). Obviously high-intensity lighting (in the 250-400-800-1000W range) should be much further away (at least 12 inches).

Here is a pretty in-depth article on LED wavelengths relating to plant growth: