foot candles

[aries23]

What type of light would i need for 500-1500.
" " 1500-2000.

Thanks Orchids I would like to purchase from Andy's Orchids say " indirect light - shade" But states the Foot candles as being one or the other as mentioned above.

Thanks again.

[mayres]

You get achieve 500-1000 foot candles with cheapie fluorescent shop lights "if" you keep your plants very close to the fixtures. To get to the higher numbers noted you will have to investigate purchasing T5 fluorescent OR even metal halide or sodium vapor fixtures/bulbs. The majority of home growers will select the T5 option.

[trdyl]

Also direct morning sun from an east facing window will also suffice.

[RJSquirrel]

a T5 HO lamp produces a 6500k spectrum which is as close to equitant sun at high noon as you can get without being there...you dont have to go HO as other T5 colors are available...the FC rating on the 28watt 4 ft lamps is around 2600 t0 2900 FC and those seem to be the choise of home growers of all kinds of things..you can buy the bare fixtures at Home depot for 26 dollars each for single lamps and the tubes are about 8 bucks each if you are handy with some minor wiring..its better than the 90 bucks plus they want for one that says PLANT light on it and does the same job...500 to 1500 FC is not much light IMO and after I changed out the little 500 FC plant light I had and put the T5 in ..wow..all the plants were getting enough light now to properly transpire and start using the food it was getting.You need the light for all kinds of things and proper transpiration allows the plant to grow healthy and wise

am I right ? please correct me if not so

[goodgollymissmolly]

Time for a physics lesson. The foot candle is a light intensity measurement, not a light flux measurement. So if you take a light meter and measure the light to take a picture, you only care what the light is while the shutter is open, not what it is seconds before or after. In the case of using flash it might be near totally dark before and after the flash.

So it makes sense that keeping your plant in darkness except to flash it once a day won't work no matter how many foot candles you flash it with. Also foot candle says nothing about the wavelengths of the light measured. You can illuminate a plant with green monochromatic light as much as you wish without good results because plants are green since they reflect (rather than use) green light.

One has to make some basic assumptions in order to use such a basic number. First assumption is that the foot candle recommendation assumes a day length...say 10 -14 hours of light at that intensity. Second assumption is that it is sunlight (full spectrum) white light or at least an an acceptable substitute for that.

So when you use foot candle, you are assuming the reader knows that means for a reasonable time approximating day length and and an acceptable spectrum for chlorophyll absorption.

In short you are saying this light intensity for a day and with a full spectrum of wave lengths. Think about it.

BTW...you can use this to your advantage by supplying less than desirable foot candles for longer periods, but there are some limits to this. Plants need a period of darkness.

[RJSquirrel]

switch from regular plant fluoros to T5?

someone else been here and done all this for us