Question
the plants that i am most concerned with are my bird of paradise, an orange tree that is 2' tall, both were given to me in late summer and still exposed to some "pretty good sun" while the bird of paradise was pretty small 8"-10" high with 3-5 main leaves new sprouts started in late fall and started to look un-healthy. for the past 3-4 weeks I've been using a couple of white "grow lamps" and they seem to be doing great! rapid vertical growth! I'm just wondering how much light is too much.
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Hello
how much light is too much for an assortment of indoor house plants? approx. hours per day? (all plants seem to be doing very well without very much regulation.)I know that this question is very vague, but any insight would be appreciated. I've installed grow lamps and would like to have them on some sort of timer.
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Scott, It depends on the houseplants - some are full-sun, some are low-light. Flowering plants almost always need more light, but even Impatiens and Begonias will bloom in a windowsill with no extra help from you.

It sounds to me like you probably have undemanding foliage plants that don't need huge footcandles to thrive.

Gro-Lites/Gro-Lamps etc. are high-wattage bulbs with an extra boost in the far red and/or far blue light spectrum.   Far Red is just next to invisible infra-red; plants need exposure to Far Red for flower production, but nothing else.  Far Blue is right by the ultra-violet band; plants need that for photosynthesis and leaves.  Foliage plants will be very healthy with only the Far Blue spectrum because they are not expected to flower.  Most foliage plants have unimpressive flowers anyway.  But if you wanted to grow begonias, you would not be pleased with results under Far Blue.  So that's what, theoretically at least, a Gro-Lite would solve.

Far Blue light is the specialty of Fluorescent lights.  A fluorescent light tube (and there are lots of "colors" of these, with various names, but they are still fluorescent fixtures) concentrates Far Blue light in its tube and gives you more bang for a buck.  Most of the energy of a Fluorescent tube is spent making light.  That's what gives them the reputation for energy efficiency.  However, you need a Fluorescent fixture to screw them into, or you can't use them.  And this is what the Gro-Lite market is built on - people who don't have those.  It's so convenient to screw a Gro-Lite into an inexpensive little incandescent contraption.

Tell me what house plants you have - even if you just tell me they are strictly foliage only.  If you are growing Geraniums, you have a problem.  Which I can fix.  rsvp

Answer
Glad you mentioned that - these plants require all possible sun. They grow with full sun exposures. And to get them to bloom of course you need Far Red, not just to get flowers but to get them to set fruit. Bird of Paradise is very slow growing and takes years to bloom but depending on the size you started with it could be blooming as we speak.

The only problem with the Gro Lamps besides the cost of electricty is the heat they generate.  If your plants are not close enough to the lamps, they will not be getting the full dose of sunshine that you are paying for.  On the other hand, if the leaves are hot, that is too close - and you will have to deal with THAT!

Otherwise it sounds like you are building up your green thumb muscles very quickly.  These can be challenging houseplants.  If they're thriving now, they'll only get better as you get more experience.  Practice makes perfect.

Not to repeat myself, but you CANNOT give these too much light.  Light is what they use for photosynthesis.  Some plants will burn in a heartbeat.  Not these.