We're starting an indoor garden and have a few questions about lighting and such.
1. What should I use, T8, T5, or red/blue led. Are the red led strips any good?
2. What's the optimal distance between lights and plants?
3. We're trying to decide between lamp=heat or ted=grow mats. Which is the most cost effective?
4. Should you germinate in the dark or does it really matter? Is just keeping the humidity up enough? We thought about a germination dark-room or covering the germinating trays with a thick flexible plastic cover. Now we just put ag-fabric on top and things germinate ok in 2-3 days. Never done it indoors.
5. How should you regulate humidity. We are in a pretty humid area and it can be a show-stopper in winter.
6. Is there anything else about growing indoors that I should be watching out for?
I guess I'll answer my own question since I've done some research and trials since I first posted.
1. T5 florescent work fine, provide full spectrum, and if you are just growing microgreens, they should be fine. A more important factor might be the heat. Led lighting is more for flowering plants, but I think can aide the growth, it's mainly a cost issue. There are cheap red/blue led strips that might accompany T5 florescent.
2. Optimal distance I think is 5-10 cm. Especially if you're using cold lighting, it won't burn the plants.
3. I've been told by a very informed person that heat mats are okay for small production, anything over 5 trays would probably have to be heated differently (full room heating).
4. We just finished germinating indoors and they germinate fine covered. I really am not seeing much of a difference, but it may depend on the kind of seed you're germinating.
5. If you're lucky enough to have a rocket mass heater that takes the humidity down, you can do that. If you don't have that luxury, you might need a dehumidifier. So far seeds are germinating and growing without much trouble at 50% humidity (if I remember correctly)
6. Measure and calculate wattage on everything and try to access how much you're going to be spending per unit of production or as an recurring overhead cost. Try to make watering automatic, which means both spray and drip irrigation being on a timer. Make sure you're okay with health regulations and all the bureaucracy in general (all of these things I'm currently doing before setting up a full operation).
I haven't tried it, but for lighting I have heard that people have had good success using a combination of two different cheap fluorescent bulbs. One should be a "warm" bulb while the other should be a 5k "cool" bulb in order to get a fuller spectrum of light.