According to the University of Missouri ( http://extension.missouri.edu/p/G6515 ) â¦

âÂÂPotted citrus plants prefer bright light for best growth and fruiting. You may keep them at medium light intensities during midwinter. The calamondin orange is the most popular potted citrus, although Meyer lemon and Ponderosa lemon are also satisfactory for home useâÂÂ.

They define âÂÂmedium light intensitiesâ as being between 250 and 1000 foot-candles, saying that the best growth occurs above 750 foot-candles. Keeping the lights on for 16 to 18 hours a day is also suggested.

I donâÂÂt know the size of your plants but IâÂÂd think that, to properly cover anything other than very small plants, youâÂÂd need more than one light. IâÂÂd also suggest a kelvin rating of 5000K or higher.

A CFL bulb (with a clamp-on reflector) rated at 2600 lumens, kept about 10 inches from the plants, would result in the plants getting somewhere between about 1200 and 1600 foot-candles (depending on the size and reflectivity of the reflector) of light intensity. One such bulb can be seen by clicking the link below. Bulbs like this should be available at most local hardware or big box stores. How many youâÂÂd need would depend on the number of (and size of) your plants.

Hope this helps,

Art

Here is a link that might be useful: Good Example

This post was edited by art33 on Sat, Jan 18, 14 at 19:50

art33, thanks so much for the tidbit "A CFL bulb (with a clamp-on reflector) rated at 2600 lumens, kept about 10 inches from the plants, would result in the plants getting somewhere between about 1200 and 1600 foot-candles (depending on the size and reflectivity of the reflector) of light intensity."
That is the most useful info I've seen posted about CFL use.