Flourescent lights

[jamromhem]

I was doing some research on fluorescent lights the past few days and felt I should share some of it.

This is my first post on the Forum BTW, So hello to all. lol

I am new to hydroponics and spend a lot of time researching on ways to do things to try to get as much information as I can on the subject.

This is something some might know already and this is not a direct reply to anyone specifically. It is just a knowledge find I felt would be useful to some to share.

People often use 3 "flavors" of fluorescents.

6500K
5000K
2700K

From what I have seen.

My research on what I the plants need for their growth is that 5000K lights, while sufficient, are not optimal for plant growth. They lack most of the light that Chlorophyll A requires and barely touches part of what it needs.

6500K is a preferable "temp" for the vegetative growth of the plants, as it covers more of the spectrum of the plants photosynthesis.

2700k Is still fine for flowering and "fruiting".

I have seen people say they are using 8000K lights. Those are way overpriced and don't contribute much to the plant more than 6500k lights from what studies have shown as the wavelengths that plants use.

I hope this was informative to some, and will be useful to anyone wanting a little bit of information on Fluorescent light "temps".

I tried to format it in a way that would be good for some of the active members as well. *Waves at GPS* I have probably read about 1/4 of the forum before posting my first post lol.

[furniture@finewoodstudio.]

I had a like question in the prior post as to what light is required to ripen fruit. In my research I came across this link. As the person to replied to my question said if the correct spectrum and amount of light that is needed. The only change I make to the article is that tomatoes required 40watts/sq ft not the 30 that is mentioned.

The article is "fluorescent lights for Plant Growth: by Wayne Vandre, Horticulture Specialist" Cool House Hydroponics - Fluorescent Lights for Plant Growth

[jamromhem]

ok.. Read through the article and I might be able to expand on it in terms we use a bit more often.

I am using one of my 2600K bulbs as an example in this.

My bulbs use about 32W and provide 2475 lumens. I pulled up a few calculators, and that comes out to about 230 foot candles (x4 for 4 ft) equalls 920 ft candles.

My bulbs are obviously more efficient than the ones that they use in the example. The one in the example provides about 20 ftcandles per W and mine about 28 per watt.

So, needing 40 W per ft for tomatoes with their bulbs would mean to those using 77 lumen per watt bulb (compared to their 58) could use around 30W per ft. So you would only need 3 tubes running instead of 4. That being said I think the configuration of your light will make a huge difference.

If you are hanging your lights above the tomato plant I think you should stick with the 4 or more bulbs... If you are running your lights up the length of the plant you might just be able to get away with 3 T8 bulbs.

This is in no way a proven fact. Though I have seen people grow tomatoes with a lot less light than most people use, by having their lights run the length of the plant rather than shine down on it. Running the light virtically lets you maximize the light use rather than the light being almost worthless to the plant by time it hits the bottom leaves, or reflects off of something else to get to them. Light from flourescents loses about 1/4 of it's strength per foot, past the first foot. I hope my thoughts on the artical are useful to some :P This was more of a think it out post than a already had it all written down and practiced and known. and I hope that I was able to help someone atleast think about their flourescents a bit to try to find a more efficient use of them.

[T'Mater]

All i ask is plz make sure to post pic's. If you'll look i made a post cause i couldn't ever get my plant's to even start growing flower's and my plants were huge. I prolly didn't wait long enough (i'm pretty impatient) after i changed my bulbs, so i moved my indoor to outdoor and all i can say is what a difference true lighting can be.

Will be very interested in seeing how well you get your set up to work. Also if you read through my post about not getting blooms, i think GPS not 100% sure tho. anyway someone posted a few links to some video's on a guy that was growing all kinds of neat stuff indoors with lighting.

[jamromhem]

I am insterested to see about it as well.. I have seen many videos on youtube showing people getting a good tomato crop off of flourescents in a basement. I will be using flourescents on my tomatoes, but I havent gotten them going yet.

Some of my tomatoes will be both flourescence and natural mixed, and others will be just flourescent lights with whatevery natural happens to bounce over to them from the window. I live in an apartment so I have to use artificial lighting where there isnt enough natural. The tomatoes will be getting started here in a bit. I will probably be starting about 5 different types of indeterminates when I get it all going. I will be posting pics as much as I can along the way.

I have also seen a lot of people have blossom drop from having the nutrients too high as well as temerature problems. There are a ton of things that can cause the tomatoes not to produce... I will keep you updated when I get my tomatoes going. It is still probably a week or two before I can even try to show you anything of use though. If not longer

[crad]

cool another person who wants to grow indoors. you are correct on couple of things. I got 8000K bulbs from menards for less then dollar difference from 6500K. I actually have measure the foot candles and have 980ft candles on the pipes. I mixed my tomatoes and peppers together and hopefully this weekend I get them separated.

I have not even started mixing the light colors and have some peppers growing but no tomatoes. I have designed a light rack for putting the lights vertically and facing one another I will actually have to buy a better quality meter as it maxes my out. but you assume tomatoes will only be 4" high my are taller and i am starting to trim the tops as well as the roots.

now my physical light costs are starting to get expensive so I am back at what GPS says you need to use HID I am trying to save costs as HID are spendy to burn and they increase cooling costs and should lower heating costs.

The real question is can I recover the costs in vegetable production. I will not be able to tell you that until spring. I am hoping to start building our green house(s) this fall yet.

I am just getting out of bed as my shifts have been change to compensate for an injury at work so this is off the top of my head. GPS has been correct more then once on here so he is good resource. nice to meet you jamromhem.

[LGWayne]

Check out the Jiffy light with adjustable stand and timer

https://ferrymorse.com/collections/hydroponic-growing-1