Question About Grow Lights?

[Pigzzilla]

Can I mix different types of florescent bulbs? I have a 4' fixture with 2 48" T12 plant bulbs I am currently using. Have an extra shop light that has 2 48" T12 regular bulbs. Can I use them side by side? Or put 1 of each bulb in each of the fixtures? Does it make a difference to use plant bulbs or are regular shop lights just as good? Not to mention a whole lot cheaper. What about T8 bulbs or T5.
I am going to make mark groleau's DIY grow light support and want to use the correct lights. Thanks, pigz

[amideutch]

Pig, here is a link showing a fixture I built using grow lites and cool white tubes together. And here is a picture of my present fixture I built using Vita Lites and 6400K CFLs. Ami

http://www.tomatoville.com/showthread.php?t=8186

[willyb]

Have a look at the link below. Good test run with different brands of lights. I use GE Plant and aquarium and GE Kitchen and bath. Good results. Bulbs are cheap. Keep them no more than 1 inch above plants 16 to 24 hours a day. Mixing bulbs works fine.

http://www.waynesthisandthat.com/fluorescent.html

[Doug9345]

Originally Posted by Pigzzilla

Can I mix different types of florescent bulbs? I have a 4' fixture with 2 48" T12 plant bulbs I am currently using. Have an extra shop light that has 2 48" T12 regular bulbs. Can I use them side by side? Or put 1 of each bulb in each of the fixtures? Does it make a difference to use plant bulbs or are regular shop lights just as good? Not to mention a whole lot cheaper. What about T8 bulbs or T5.
I am going to make mark groleau's DIY grow light support and want to use the correct lights. Thanks, pigz

Electrically you can mix T12's with T12's, T8's with T8's and T5's with T5's. Each fixture should have the bulbs it is designed for in it. From my experience regular tubes do just as well as grow lights. I often use CFLs. They work fine.

Brightness seems to be the important part. I think you'd gain more from spending the difference between the grow lights tubes and regular tubes on a better fixture.

The problem with the cheap T12 "shop" lights is that they don't typically run the tubes as bright as as regular fixture. We are talking the difference between 25watts per tube and 34 watts per tube. It's the ballast in the fixture that determines how bright a tube is.

[ChrisK]

There is no reason to buy the more expensive bulbs to start plants. Cool white work perfectly for starting plants.

http://www.uaf.edu/files/ces/publica.../HGA-00432.pdf

[Pigzzilla]

Thanks to all for the answers. For next season I will use T8s. Hubby has a stash of those in the shop. He doesn't know that I know where he hid them. He purchased way too many when we built the shop, he has 6 'extra' for if he decided to make it brighter than July. I'm not real sure where the T12s came from but I'm using 1 and going to grab the other for my setup......pigz

[Hotwired]

It depends what you are growing. Are you starting seedlings inside for eventual transplant outside, or are you trying to flower and fruit inside? Foliage Growth takes primarily Blue Light (5500k-6500k), while Flowering requires the addition of Red light (2500k-3500k). The PAR curve is spectral curve that a plant requires. Here's a standard Daylight Florescent Spectral curve compared to the PAR curve http://imageshack.us/a/img560/3693/daylightcflcurve.jpg . If you are flowering inside then you should add a warm white bulb http://imageshack.us/a/img543/3018/w...tecflcurve.jpg .

I'm a retired optical engineer, and have run spectral curves on most of the professional growlights. In my opinion, the cost is not worth the benefit, and CFL's or Fluorescent tubes have much more bang for the buck.

Hotwired NY 5b
http://www.hotwiredgardens.com

[greenthumbomaha]

Ami, I noticed you started seeds on my birthday (mid-October)! I'm honored! What do you start at this time of year?

Hotwired, and other light experts -a member recommended this light in another thread

Lithonia Lighting 4 ft. T5 White Grow Light
http://www.homedepot.com/h_d1/N-5yc1...1#.UMyUzIM80uc

similar product:
ViaVolt 4 ft. 4-Bulb T5 High Output Copper Fluorescent Grow Light Fixture
http://www.homedepot.com/webapp/wcs/...6#.UMyRoIM80uc

I'm currently using regular T8 shop lights on storage shelves in a southwest facing window, one set of 2 per shelf. Next year I would like to add another shelving unit in a north-west window. So many new seeds to try. Your opinion on the upgrade much appreciated!

- Lisa

I am keeping my fingers crossed on growing out the dwarf seeds indoors too.

[Hotwired]

greenthumbomaha ... I'm familiar with the lights. The ViaVolt 4 ft. 4-Bulb T5 High Output Fluorescent Grow Light Fixture (with 6500K 54w bulbs), is almost exactly what I use, except I made my own with some custom reflectors. The $138 price is a deal for what you're getting. Just be careful of the K-value of the bulbs. It seems that some ViaVolt lights have 5000K and others 6500K bulbs.

Here's what I use. It cost me $90 for 20,000 lumen for a 216-watt 4-tube 24"x48" growlight with what I consider the optimum spectrum for starting plants inside. I use (3) T5 54-watt 6500K 5000 lumens fluorescent tube http://store.bulbstock.com/32423.htm...FUKd4Aod9R0AdQ and (1) T5 54-watt 3000K 5000 lumens fluorescent tube http://store.bulbstock.com/32422.html . The cost of the 4 bulbs is $39.80 ($9.95 each). This gives me 20,000 lumens and an effective coverage of 30" x 50". I used a standard 24"x48" 4-tube T-5 fixture. I got a bunch of 4-bulb fixtures on Freecycle and I swapped out the ballasts for 54 watt http://www.lightbulbsdirect.com/Merc...Store_Code=001 .

If I was using 2-bulb units I'd use two 6500K tubes. Keep in mind that a 5000 lumen bulb is the output in all directions. Even with good reflectors you can't get better than 2000 lumen directed toward your plant. I'm pumping about 7,000 lumen from my 4-bulb 20,000 lumen light onto my 4 trays (6" distance), which is 6.1 lumen per square inch. Noon Sun on a clear day projects 22 lumen per square inch, and 2.3 lumen/sq-in on a overcast day.

[casino]

This is all very good and usefull information, thanks guys.

I still use shop lights (one warm and one cool white) because I have the fictures. When they burn out I will switch to either T5 or wait for the LED lights to become affordable. The LED lights have their own unique properties.

What I know about light from my master gardening class is the color we see is the spectrum of light that is not absorbed by what we are looking at but rather what is reflected back to us. The color black absorbs the entire light spectrum. The color of white represents the entire light spectrum reflected back to us. Green is the color of chlorophyl so the light spectrum of green is not used by plants, thats why we see green. So we dont need to supply the entire Full daylight spectrum but rather focus on what light plants need.

A juicy tid bit. Plants don't need ultra violet light to grow, the light that burns our eyes and skin. Except for a particular cash crop that is usually grown indoors seems to flower better when exposed to periods of ultra violet light. I find the hydroponic stores very knowledgeable about light. They are moving away from the sodium lights, the energy hogs that produce a lot of heat, are now mowing towards the T5's because they are more effecient and cooler to run.

[greenthumbomaha]

Very informative. I thank you for sharing those well thought out components and sources. You are lucky to have Freestyle, I still need the "housing". A friend suggested I attend the monthly city seized property auction. I bet those bidders are looked at pretty closely.

[ChrisK]

Check out craigslist in your area. I found 4 bulb T8 electronic ballast fixtures for $22 each.

[Cole_Robbie]

Originally Posted by casino

A juicy tid bit. Plants don't need ultra violet light to grow, the light that burns our eyes and skin. Except for a particular cash crop...

I know you're not talking about the coca plant, but along those lines I read that for some reason it is only coca from South America that is worth making into cocaine. The plant can be grown anywhere, indoors or out, but it will have only a tiny fraction of the alkaloid that makes cocaine if it's not grown in the Andes mountains. It has been theorized that the ultraviolet light of the high altitude is the reason. That's why South American drug cartels will never go out of business - no one else can make their product.

[checkerkitty]

Thanks for all the info everyone! I pulled out my light fixtures yesterday and only one is working. Off to the Habitat Home store and Lowes I go today. For those of you interested in LEDs, look at ebay if you like DIY. We have saltwater fish tanks at home. My tank is lit by LEDs only. DH built the fixture himself. Emitters and drivers are readily available. We just got a shipment of replacement emitters in about a week ago. I will say this about LEDs. Don't let them get too hot! When DH built my light fixture, we asked our local guy we bought our first emitters from about cooling them with a fan. He told us we didn't need one, just the heat sink was enough. Not true. We lost several emitters. We put a small computer fan in the back of the fixture to blow across the emitters and heat sinks and haven't had a problem since. Maybe someday I'll get him to build me an LED plant fixture.

[casino]

I attended a seminar by Dr. Robert Halgren on growing orchids under LED lights. From his web site these links will send you to his Utube home made videos, cute but What I find interresting is the color of his plants growing under LED light. Now watching his Utube video there were other same subject videos to watch on growing under LED light. what I find interresting the environmental growing conditions changed because LED's dont produce heat and they talk about that condition.

http://www.littlefrogfarm.com/ is the home page for Dr. Robert


Some videos: Not the highest production quality, and I narrate like I teach - completely on the fly. If you can get over that, there is some good information in here.

• A tour of Littlefrog Farm's growing area
• A deluxe setup using GlowPanel 45W LED units
• A GloUFO - 90W LED unit over some orchids and broms
• A GrowPanel Pro (300W) over some orchids, etc
• A little experiment comparing LEDs to greenhouse - my first videos. A bit long... Setup Results

On a side note: This is very interresting
http://www.youtube.com/watch?v=xJIjJ5nZUZw growing with LED's LOL