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After transplanting (indoors)

Posted by MWAGT z5b Nebraska (My Page) on
Sun, Oct 2, 05 at 16:01

After reading through 5 pages on this forum as well as the FAQ's on the Seed Starting forum, I still have a question regarding which fluorescent bulbs are best for both vegetative growth and the flowering/fruiting stage.

I have a 4 foot 2-bulb shoplight. I've actually started a few seeds under a 2 foot 2-bulb shoplight to get them through the seedling stage using cool white T-12's.

Now that I've purchased the 4 foot shoplight to use after I transplant the 5 seedlings, I need to know what type bulbs really will work best. I've read about several different types on here.

I'm under the impression Cool Whites are best for vegetative growth, and Warm Whites for flowering and fruiting. Although I'm also reading on here about Sylvania Gro-Lux (standard) and GE Chroma 75.

Should I just use 2 Cool Whites during the vegetative stages? Or 2 Grow Lux's? Or one of each? Or a Gro-Lux and GE Chroma 75?

And what would you use for the flowering stages? I'm guessing the best is to use either a Cool White and a Gro Lux combo, or a Gro Lux and GE Chroma 75 combo, or a Cool White and Warm White combo. Or would it be better to use 2 Gro Lux at this stage? I really want to make the best choice. So any advice will be appreciated.

Thanks, Jeff


Follow-Up Postings:

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RE: After transplanting (indoors)

Jeff, what type of plants are you growing and how tall will they get?


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RE: After transplanting (indoors)

  • Posted by MWAGT z5b Neb (My Page) on
    Sun, Oct 2, 05 at 20:32

I'm trying tomato right now, but will try hot pepper later. I know I need to keep the plants to probably no more than 2 feet max since I'm dealing with flourescents.

Thanks for the reply Watergal.

Jeff


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RE: After transplanting (indoors)

please advise me about under light growing...i do cuttings and have small seedlings and mini roses...
i know little about what im doing and need help..
suzanne


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RE: After transplanting (indoors)

  • Posted by MWAGT z5b Nebraska (My Page) on
    Sun, Oct 16, 05 at 11:30

I see no one answered our questions Suzanne. So I'll give you a couple of suggestions or at least tell you what I've learned.

My indoor garden will consist of hot peppers and tomatos primarily. I'm using a 2-bulb 4-foot shoplight I bought for less than $27. The bulbs came separately. I ended up using 1 Cool White and 1 Sylvania Gro-lux (T12) flourescent bulbs. The Cool White bulb came in a two-pack for $4.99 and the Gro-Lux was about $5.49 or $5.99, both from Menards.

The reason I'm using one of each type of bulb is for the light spectrum each puts off. And I also wanted to make sure I used 1 Cool White because it puts off more lumens than the Gro-lux.

For starting seeds through the seedling stage, and for vegetative growing my shoplight will be good enough for a few plants. I'm guessing I'll be able to get 4 10" pots under the light. With flourescent lights I've noticed I have to keep the light as close to the top of the seedlings as possible for best results. (Without touching the leaves of course.)

The flowering/fruiting stage will be the biggest challenge for me. From most of what I've read, flourescents aren't strong or intense enough to use for this stage. That's where you'll see people talk about Metal Halide (MH) and High Pressure Sodium (HPS) lighting systems.
MH is better for the vegetative growth stage, and HPS is better for the flowering/fruiting stage. There are actually lighting systems that allow you to use an MH bulb for growing the plant then switching to a HPS to flowering.
The MH and HPS systems will set you back a couple of hundred dollars, run your electric bill up, and you have to be mindful of how much outlets at home can handle (i.e. amps). These expensive systems could potentially cause fires if overloaded.

Buying those systems doesn't make sense for me right now at least. I'd just like to experiment to see if I can grow some jalapenos and tomato plants to full fruiting maturity. Maybe I'll buy a 2nd shoplight or a couple of compact flourescents to supplement my primary shoplight flourescent to attain more lumens.

It's all an experiment for me right now Suzanne. I don't know how this will work for your mini-roses to be honest. For cuttings I'd suggest having a mini-greenhouse (my Jiffy was about $32) so you can cover them with the plastic lid until the roots start to get good development. My Jiffy also has the heat mat which helps keeps the soil warm from the bottom.

The only other things I can suggest is length of time you have the flourescents on per day (for seedlings up to 24 hours), and be careful not to overwater/underwater or over-fertilize.

Hopefully I didn't confuse you too much. Maybe now some of the more experienced indoor gardeners will give us some advice.

Jeff


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RE: After transplanting (indoors)

I don't know about growing tomatoes or peppers under lights, although I've grown many other seedlings. So I'll just offer some general comments.

I don't think you'll find much difference between the available fluorescent spectrums for growing on seedlings. Personally I use whatever is available for seed starting and a 50/50 mix of daylight and warm white bulbs for growing on seedlings.

Cool white bulbs may appear to put out more light than gro-lux bulbs as measured by your eye or as measured by lumens. In fact both bulbs put out roughly the same number of photons and that's what the plants care about. In fact there is an argument that the gro-lux puts out more useful photons.

The idea that you can lose lower light intensities for vegetative growth than for flowering and fruiting seems flawed to me. Light which it too dim for effective flowering or fruiting will not grow a healthy plant. If the fluorescents you are using only produce good seedling growth when almost touching the leaves then you are going to need more light very soon because the tubes will get further and further away from the bulk of the leaves as the plants get taller. You might want to consider T5 tubes (more tubes in a smaller space), better reflectors (less intensity dropoff with distance), vertical fluorescents around the plants (more even illumination of the whole plant), or more light (probably from a HID source).

I just noticed you have 1 2x40W light. That will be completely inadequate for growing even a single tomato or pepper plant (although a single compact 80W bulb might be adequate for one or two plants). As a quick rule of thumb, plan on at least 20W of lights per square foot of illuminated area, and probably quite a bit more for tall plants. If all your plants will fit into an area less than about four feet (fluorescent tube length) by a couple of feet (for at least two shoplights) then consider a compact fluorescent bulb or an HID bulb. Metal halides are available in 250W power for smaller setups. Smaller bulbs are also available, but efficiency is lower and you should probably stick with fluorescents.

Using lights 24/7 may or may not be effective on seedlings. I believe that tomatoes is one of the ones that respond well to this, but some other plants don't. Adult plants will not like it.

Spectrum and flowering. The "rule" is blue light for vegetative growth and orange/red for flowering and fruiting. The rule is wrong. Vegetative growth is produced most efficiently by far red photons (which are best for producing photosynthesis) with approximately 10% blue photons (to power certain plant metabolic processes). Light sources that actually do this are not really available at present. The Gro-lux type lamp is an attempt to get close. The stimulation of flowering and fruiting that occurs with most red and orange light sources such as HPS is because of the balance of red and far red light and also because of very low levels of blue light (essentially none with an HPS lamp). HID lamps with mainly far red and some blue light are not available, so metal halide lamps must be used to provide sufficient blue light to prevent the onset of flowering. Commercial growers often use HPS lamps for efficiency with supplmental blue light to prevent flowering.


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RE: After transplanting (indoors)

  • Posted by MWAGT z5b Nebraska (My Page) on
    Sun, Oct 16, 05 at 17:34

Thanks Shrubs n Bulbs. Looks like I'll have to do some reading on those compact T5's. I did buy an aluminum cylinder looking reflector that might be for T5's. Not sure though. I bought it at Home Depot and also bought a 120W grow bulb there. The light was way too intense and hot to use for my pepper plants. I couldn't get the light close enough to the plants without basically melting them. Plan B was the 4-foot shoplight, but it seems that wont be good enough by itself. I will check out the T5's now.

Thanks for the very informative info.

Jeff


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RE: After transplanting (indoors)

The T5's I have seen are nearly as expensive as the HID lights. I started some tomato plants way too early one year, and I was able to get them about a foot to a foot and a half tall, a bit lanky, under 2 four foot shop lights with one cool and one warm bulb in each (cheapest bulbs they had). I got some flowers and even a tiny green fruit but then the plants seemed to stall out. There was also some west window light supplementing the electric lights.

I bought a 400 watt MH HID light to use for some tropical hibiscus. I like it, but it's still not bright enough to create many blooms over the large area I have. It does overwinter the foliage nicely though. I believe hibiscus and tomatoes/peppers have similar light requirements. I should have bought the 1000 watt but that would have overloaded my circuit.

The shop lights work great for seedlings and cuttings. Cuttings do much better if you put a plastic dome over them to keep the humidity in and keep the soil moist. I used to grow a minirose under them and it worked fairly well - got a few blooms even, but you must watch like a hawk for spider mites and treat promptly.

I'm going to experiment this winter by adding a 160 watt Wonderlight, a cheaper grow light, for more oomph. I'll let you know how it goes


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RE: After transplanting (indoors)

  • Posted by MWAGT z5b Nebraska (My Page) on
    Sat, Oct 29, 05 at 10:12

I just re-read the replies. The info did help out alot. I ended up getting a 2nd 4ft shoplight. At present I have 2 plants in 10" containers under each shoplight, and 1 plant in a 3-gallon container under a 2 foot shoplight. That 2 foot shoplight will be removed today and replaced with a compact flourescent. It's a 42-watt compact but it comes advertised as a 150-watt light. Perhap that's what they mean by high output? Anyway, I screwed the compact bulb into an aluminum cylinder looking fixture that I bought at Home Depot for about $10 or so. It can handle 300 watts. I have a feeling that'll be better than the 2 ft shoplight.

It'll be a learning experience. 4 of the plants are 4 to 5 inches high now with decent branch and stem growth. The 5th germinated 1 1/2 days later and has been lagging behind ever since. It's about 3 inches high. I did transplant all a week ago with no ill effects. Although I have cut some leaves off that were apparently developing some type of fungus. Possibly from getting wet when I misted the soil during watering.

Just thought I'd update those who replied on how things are going. Thanks again Shrubs-n-bulbs. The info was useful. And Watergal, hope you let us know how things go with your Wonderlight.

Another question if someone has time to answer:

I'll be using that cylinder shaped fixture by hanging the cord over the wood (what's it called? can't think! where you hang your clotheshangers on.).
If I were to hang say 2 or 3 of those cylinders over that wood piece and plugged them in, would the current from each cord somehow affect the other fixtures and cause them to fry or anything like that?

I know there's a better way to ask that question but it's Saturday morning and my brain seems to know it. Sorry.

Any advice on that would be appreciated. Thanks, Jeff (Man Without A Green Thumb)


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