Incandescent grow light, waste of money?

[OOAJ]

I know that most of the grow lights that are used are either flourescent or the high pressure sodium? bulbs, I was wondering if an incandescent bulb could be used as well. I ask because I'm a windowsill grower and as the days get shorter I was looking for something cost effective to provide a little extra light, rather than act as a primary source.

I picked up a 60 watt grow bulb at home depot and have it set up close to the plant with a timer. It definitely adds some extra warmth which is good, but I was wondering if the light it's producing was worth the electricity I'm burning.

Thanks in advance.

[silken]

I'm no expert on lighting but we just had a presentation at our society meeting on lighting and it was said that incandescent is pretty much a waste. However if it is close over a plant or two and being a 'grow' light it may be the correct spectrum. Then it has to do something. But if it is just a screw in normal light bulb, replacing it with a screw in fluorescent would be better for the plants.

[OOAJ]

I do have the light very close, just a few inches above the plant so that it isn't touching/burning the plant.

Also, I did look for a twist style flourescent, but my home depot didn't have anything that would be good for growing; is this typical or is my home depot just kind of lame?

[silken]

The normal twisted screw in bulbs are at my Home depot, but nothing with special grow featurres. My Phals seem to respond well to a regular one.

[Ray]

Here's the problem with incandescent grow lights:

An incandescent bulb puts out light that is about 100x red and 1 x blue. In order to "boost" the blue end, they actually have to filter out the red end - essentially reducing the lumen output significantly.

An incandescent bulb starts with about 18 lumens per watt (compared to 90 for a T5 fluorescent), so filtering clobbers it.

[johnblagg]

well not really that good but they will help some ...myself I would consider them wasted money since a cfl of high wattage woud do much better for less energy cost

[littlefrog]

Higher efficiency does pay for itself pretty quickly... Modern CFL (compact fluorescent) bulbs are pretty darn good, and look almost like natural daylight if you spend just a bit extra money. They last a long time, but not forever. 5-7 years, supposedly. At 14 hours a day, maybe less.

If you want to spend way too much money for ultra efficiency, LED bulbs are the way to go. Price will come down in the next year or two. I'm already seeing low wattage white LED lights about half the price they were a year ago. Higher wattage ones (more suited to plant growth) are still quite expensive. They should last for 10 years plus though, might never have to change it again.

There is at least one even newer technology out there, but you don't want to get excited about it yet, unless you won that 250million powerball yesterday.

[OOAJ]

Good to know, I'll look into getting a cfl.

[Rowangreen]

Hi, I'm in the same position as you, though in the UK. I'm new to all this too, but my various plants seem to be liking my solution...

With the CFL's the thing you most want to look out for is that the kelvin value is 6400/6500k range. Kelvin is the 'colour' of the light, and that's daylight equivalent. (There's a different k value if you want to encourage blooming, but you want the daylight range for growth generally)

In fact I got a 25 watt 'daylight' bulb (equivalent to a 100 watt incandescent apparently), sold to help people with SAD rather than plants, and put it in my ceiling socket. As it's a small room, that puts it about 4 to 5 feet from my plants. I leave that on all day, and it seems to be working. Phals that were very dark are looking better.

I've also now got a 45 watt 'blue'/6 and halfish K grow bulb, which I have in a plug in extention lamp fitting (the sort you get for use in garages etc) which is closer to the plants. I have that on a couple of hours a day when I'm in. I've had to move my phals further from it as it seems too much, but some of my none-orchids are loving it, and I think the oncidiums are appreciating it. That bulb is HUGE.

I guess unless you can find someone with light guages and lots of expertise, you'll just have to play around with it! I'm sure your bulb is doing something...

[johnblagg]

...rule of thumb and pretty accurate cool white = the blue in the right kelvin and warm white = the right kelvin range for the red side a mix of the two works very nicely for me and I have good growth and they are blooming very well I dont pay much attention to catt light phal light levels ect just a good bright room .....but temperature ranges are more important dont mix cool growers with highet heat range plants and expect the same