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Indiana

Just started my pumpkins today. Wondering if I lower my florescent lights from celling to a couple inches above pots. Will this be ok? Thanks

4/28/2019 3:25:24 PM

Syracuse, NY

Everybody's different, thank God, but, i have mine suspended by clothesline rope through 2 screweyes one at each end of the fixture, screwed into the rafters with the two ropes tied together VIA knots at like 2-4-inch intervals in those two ropes to hitch around a pair of drywall screws (2 for security). in this weigh i can lower them down to at or below the plants leaves' level, securely, accurately, safely. think of it as flying two kites at once and tying them off to a post to go over and sit and watch them for awhile. many analogies, none of them very good, lol---eg

4/29/2019 4:14:31 AM

Syracuse, NY

PS---if you're gonna do what you're thinking of, you must not want leggy plants, right?
myyyyyyyyyy opinion is that if you have your plants in the peat pots for 10-14 days, leaving the lights ON for 24/7 will keep them from getting leggy even further. this has helped me over the years, as i NEVER have my outside ready for my plants, that are inside. i've never had any visible problems with it and i'm sure they get used to the outdoor light cycle real quick. mine, like anyone else's, double in size once outdoors as a 'Thank You', i'm sure -
i USE the lights as an adjustment just before putting them out;
by setting a plant far away from the lights the night before planting it out for real, it can be caused to grow half an inch or more higher or directionally than it would have if no deprivation were exerted on it---this is handy if the plant is still not QUITE high enough above the edges of the peat pot or is tilted in slightly the wrong direction...on and on and on and on...good luck! eg

4/29/2019 4:26:28 AM

Hadley Ny

depends on what type of flourescent bulbs you are using. I use t-12s and have them about an inch or two above..t-8 and t-5s might be hotter and need to be higher so you don't burn your plants.

4/29/2019 5:30:09 AM

Hadley Ny

also might want to check what bulbs are in there. You want clear daylight not cool white

4/29/2019 8:31:34 AM

North Pole,Alaska

T 12's, T-8's and T-5's can all be almost in direct contact with leaves without burns. Heat becomes a problem with HO's and VHO's. You also WANT cool whites. They have the highest output in the PRV range of any flourescent. everything outside this range isn't helping.

If you try to rely on lights from ceiling height, it will be like growing in the shade on a very cloudy day at dusk. Light decreases at the square of the distance from the source. Simply put, a light source 1" vs 60" from leaves is 3600 times stronger! The sun is equivalent to 1000 watts/sq meter at 1 meter above plants. You'll never get close to that with florescents at any distance, but you can get healthy starts with them. Main problem with weak light besides tall spindly plants is this: Plants need energy to grow. Given enough light and nutrients, the plant generates it's own food for healthy growth. Not enough of either one, though and it needs to draw from the cotylons for a food source and it wastes energy trying to "reach" light, thinking it's being shaded by a bigger plant. My plants usually still have healthy cotyledons when the main is over 10' long. I start with cool white flourescents until the age you will be transplanting

4/29/2019 1:05:21 PM

Hadley Ny

Got me on the PRV range Dave...don't know what you mean...can you help me out on cool white vs daylight..I was taught the other way.

4/29/2019 1:43:59 PM

Hadley Ny

I'm also running out of room and have 2 more sets of lights with cool white bulbs and was going to buy daylight bulbs for them. I cant plant for another month for veggies and late starting AGs. Looking for info and I will compare daylight with cool white Thanks, Retired but growing for years but never seriously until retirement.Don't want to waste money if I don't have to.Thanks T

4/29/2019 2:18:15 PM

North Pole,Alaska

Sorry, meant to type PAR, not PRV???. Photosynthetic Active Radiation. Don't listen to anyone who says they know exactly what that is. I'm part of a "Think Tank" that includes a Professor who specializes in plant lighting and there is a lot of disagreement on just what is actually utilized by plants and to what degree. Also, each variety of plant has different requirements in intensity, duration, and wavelength, which also vary by physiological age with each individual plant! Confused yet? to make it worse, there is no true way to compare different light sources, and manufacturers compound this by publishing the specs that make their light sound the most promising. It's like trying to compare apples with oranges with plums with cherries.There are NO true conversions from 1 type of unit to another that actually tells you how much USABLE light you are getting from a light source to your plant at a set distance, (also the light at the top of a plant gets more than the light at the bottom , and leaves directly under a light get more than those a few inches to the side. That's 1 reason published research articles give Exact specs of light type and distance from canopy.) If LED's are used, manufacturers Model number is also given, because LED output varies considerably in frequency and lumens per watt

4/29/2019 4:14:54 PM

Hadley Ny

Dave, Thanks for the reply..you had me swingin'. I'll put up my other 2 sets of lights with the cool white and see if there is a difference. I only grow ORANGE and a lot of veggies..Not looking for a world record but clear light had me putting my 3 week old tomato plants outside to slow them down. will definetley need to transplnat them..My understanding is the T-5s need more space because of heat. T

4/29/2019 4:26:43 PM

North Pole,Alaska

The jist of it is cool whites 1" above the plants stacked side by side will give you the most cost effective bang for the buck until 8-10" tall. At that point you'd want to switch if you were staying indoors for plants growing much taller. At this point your goal should be a short, stocky plant with a HEALTHY ROOT SYSTEM. That will make the transition to full sunlight easier on the plant.Most seedlings also do better with only 12-14 hours per day, as long as they get true DARK the other 10.They need the rest just like babies. There are exceptions, like tomatoes, but pumpkins are too easily stressed until the roots catch up, which takes a few weeks.

4/29/2019 4:26:43 PM

North Pole,Alaska

Every flourescent gives off the same BTU per watt of heat as an electric heater. The difference is the surface area radiating the heat. A T-12 is 1.5" dia, a T-8 is 1", a T-5 is .625", so the heat from a T-12 is distributed over an area 240% as large as a T-5. I always let my plants grow directly into a t-12 without harm. 1" from a T-5 is fine.

4/29/2019 4:36:15 PM

North Pole,Alaska

I used to grow up to 20,000 # of tomatoes a year for Farmers markets. Use the tall tomatoes to YOUR advantage. Transplant them with most of the stem buried ( pull off the weaker, lower leaves) Tomatoes are an advantageous rooter. You will build up a much stronger root system at an early age, which will help significantly with your first truss of tomatoes

4/29/2019 4:40:45 PM

Hadley Ny

Glenoma ...obviously you got a differnt name again AHOLE

4/29/2019 5:29:11 PM

Oak Grove, Mn

Big T....i know enough about indoor lighting. What daveigiantguy is saying is real stuff. Trust a indoor grower that has spent hundreds of hours looking at light subjects. Not something Glenomkins knows that much about. Dont chase someone that is knowledgable away..because you think it might be someone else.

4/29/2019 6:47:50 PM

Oak Grove, Mn

daveigiantguy...glad you stopped in. I know what you are saying is truth and at a level higher than most of the growers here. Indoor growing is still in infancy. I certainly invite you to grow in next years winter tomato competition. I should have a high pressure aeroponic plant ready to go again, plus my hydro's. Currently, my go to lighting is Ceramic Metal Halide with platinum LED's as secondary. I am intrigued by the new white light leds. Dont know if I will have the funds by next winter to buy one..but I am tempted. Second place this year was from a grow store that was growing under a white led. Do you think there is benefit to light mover. I have a par meter but to get depth of light into the canopy is a great struggle. Sufficient interior lighting on the tomato plant is light toxicity at top. Like I said...thanks for stopping in...I want to know more of your experience.

4/29/2019 7:10:41 PM

North Pole,Alaska

bnot, glad to see someone else using aero. I'd like to try a tomato indoors again, but probably not this winter. Most of my space is tie up doing R&D on Ginseng in conjunction with some people from the local University.

What wattage CMH? How high above plants? Are you using the LED's as side lighting or canopy lighting? Most of the research I've seen suggests white lights effects are mostly seen when thee isn't enough light saturation in the RBG/IR wavelengths. Your Halide should provide enough there, so I would spend any precious $ on RED, Blue, Green wavelengths. Consider setting 40w flourescents vertically AROUND the plant as a light WALL. Tomatoes are one of the few competition plants that can utilize almost full strength sunlight. Are you familiar with the unit umol/m-2/s-1 ? It's the unit of usable wavelength energy alot of companies use for rating usable light.The sun is about 2000.

4/29/2019 7:42:40 PM

North Pole,Alaska

Along with that is the Daily Light Integral, expressed as umol/m-2/day. Plants have light saturation points as well as total light saturation per day. Tomatoes are light whores.
The downside to having all the light required, is the heat generated. It's a misconception that tomatoes are heat loving plants. Yes they grow faster, but they ripen even faster. Tomatoes coming out of Florida and other hot states are much smaller than the ones coming from cooler Canada. Good old Degree Days.

4/29/2019 7:51:29 PM

Oak Grove, Mn

davei.. I have been running 300 watt sunsystem CMH. I use an apogee PAR meter. At about 8 inches I am at 2000 uMols with the CMH. I have tried the CMH over the top, with 4 150 watt platinum LED's on the side. I get about 2000 uMols at 6 inches with the LED's. Obviously the spread of the pattern of the CMH is wider than the narrow LED's. I am familiar with DLI. I was calculating the DLI of the equator. I should be able to be higher. My grow room tends to run warm. That is why I can start a tomato plant Jan 1st and harvest a ripe tomato by the first day of spring. Don't disappear Davei..growers that talk in uMols and DLI are very rare here.

4/29/2019 8:05:00 PM

Oak Grove, Mn

I will have to make another trip to my grow store. Early last winter, I brought my PAR meter in and measured the Umols on their white light. The PAR numbers were as high as my 4 year old purple LED's but with the benefit of natural color to the leaves. My biggest problem with the LED's is determining nutrient deficiency with the strange coloration. Lighting is improving rapidly...good thing there is a high dollar crop that can pay for the development.

4/29/2019 8:26:54 PM

Oak Grove, Mn

Too much info to reply to...So far, I havent worried too much about IR. Two years ago, I was concerned about UV. For awhile, I was running UVB boosters. That seemed to solve much of my edema difficulties. Starting pumpkins under lights...you can do that with your eyes closed. Growing full plants under lights...whole new ballgame.

4/29/2019 8:52:52 PM

North Pole,Alaska

Definitely exponentially harder as the plants get bigger. Not so familiar with Platinum LEDs. I assume they have far red for the Emerson effect? What about green? It penetrates far deeper into tissue than red or blue , and they are starting to believe it plays a far greater role than previuosly believed. I haven't purchased a commercial LED. I prefer to customize. Steve's LED is a great place for high end LED's and drivers, and gives me the advantage of spacing the lights around the plant ( rather than the flourescents I recommended before I knew you had it well covered).

As for determining nutrient deficiencies, I just shut off my LEDS and HPS for a few minutes and turn on a cool white for color analysis.I tell the plants it's a cloud :)
As for a light mover, it's probably even more important @2000 umol with narrow field. Not sure if you know the energy pathway of phytochromes and crytochromes, but basically you get far greater energy transfer efficiencies by trying to spread it evenly, rather than spotty saturation/deficiency. You overload one pathway and starve an adjacent one.I'm assuming you already know this and am trying to pass on to "others"

Enjoying the chat, by the way

4/29/2019 9:59:03 PM

Hadley Ny

Dave, I'm sorry...get myself in trouble sometimes!! Obviously I was mistaken you for somebody else..Thanks for the feed back. Will try the cool whites. Thanks T

4/29/2019 10:23:18 PM

Oak Grove, Mn

davei...it is late..and i should be going to bed. I have 7 150 watt platinums and 7 300 watt platinums. 2 of the 300's are set to be blue predominent. The owner of the company has told me he would make any ratio I desired. Unfortunately...the blue predominent is spaced totally wrong. I have one of the 150's that about 15 led's shorted out, that I bypassed with a jumper. They all have far red. They are a full band...except for the greens...very low on the greens. I would like to modify these....have to figure out how to replace SMT lights (surface mount technology). Does Steve's offer smt replacements? I think I would change it to add more green...which would make it a white light. I am enjoying this chat also. You gave me two new terms to research...phytochromes and crytochromes. I close on a new house on friday..so my mind is somewhat preooccupied, but this subject is definitely something that i have passion about.

4/29/2019 10:52:49 PM

North Pole,Alaska

Get some sleep!!!I'll try to come back and post this weekend and steer you towards some good research papers. In the meantime, see if you can get the actual wavelengths of the LEDs (possible) and individual LED outputs per wavelength ( Not probable)and maybe I can help with some replacement LED suggestions

4/30/2019 12:53:34 AM

Morgantown, WV

LOL, happy to see another plant nerd talking phytochromes howyadoin! Been digging into the red / far red effects recently in class, and it's pretty complex stuff, but I think it is important to understand if you're involved in indoor competition.

4/30/2019 8:42:00 AM

I read some of what dave is talking about in the link on other gardening , just not as detailed.
Do you cool the temperature when plants are resting?

4/30/2019 4:03:28 PM

Oak Grove, Mn

dave, i have 3 different spectrums in lights of LED available. I could go thru and find out how many bulbs are in each band. My par meter cost much. I really wanted a spectrometer..but could not find a decent one for under $2000. I really would like one that could give me a probe and connect to a computer and measure the strength of lighting of each band. All my bulbs are Cree with 60 degree lenses. How can indoor growers solve the riddle of the Inverse-square law of light to equal the sun? Good to meet someone with shared passion. Thank you.

4/30/2019 4:52:55 PM

Oak Grove, Mn

uwwww.....my english is terrible. I just reread what I wrote. I am not sure it is understandable. Too bad there is not a 1/2 hour to edit a message post like I can with diaries. If you get confused...I probably could rewrite it to make more what was going thru my mind. Or maybe you are good at understanding intangibles.

4/30/2019 5:28:00 PM

Morgantown, WV

Spudder, the question you are asking refers specifically to something referred to as DIF or the differential between night and day temperatures.

Subtract the night temp from the day temp, and if it is positive, internode elongation is normal, as days are normally warmer than evenings. If it is negative, then internode elongation is shortened to control growth into shorter, more squat plants.

It is tricky to control, but can be done, and is every bit as effective as applying growth regulators to slow elongation, though done only through temperature.

Can't answer for Dave, but I would imagine this is critical if trying to contain an unruly plant in a smaller space.

Bob, take a nap, Dave broke your brain =p

4/30/2019 6:55:00 PM

This is why I ask. This research involves dropping the temperature right after turning the lights out and what temperatures for tomatoes and peppers.

"Not only does the temperature drop give the crop a good rest, but while it occurs, leaves cool faster (due to their large surface area in relation to volume) than the fruit (larger volume). This causes the plant to focus on growing the fruit, resulting in faster fruit growth and increased yields."

4/30/2019 7:31:10 PM

North Pole,Alaska

So..... first things first. bnot, we aren't going to solve the inverse square law but we can sure trick mother nature into thinking we did. I'll go into that this weekend when I have more time. Any chance they gave you the wavelengths of the LED's in each band? I'll go into detail on that this weekend ,too. as for understanding intangibles, well that's plant lighting in a nutshell!There aren't many things more intangible unless you want to start a thread on quantum physics.....:)
As for cooling the plants, definitely. I'll have to look it up this weekend, but I believe the ideal day/night temp differential is about 8 deg F for max tomato fruit growth. What Dustin was explaining is correct, however tomatoes are peculiar in one aspect- the greater the difference in temp from day to night- the longer the truss. Growers use this sometimes to keep the tomatoes from crowding each other.
Spudder, I haven't seen any research addressing rates of cooling, however, the premise makes sense for a number of reasons, and I have read a number of studies that clearly show better fruit growth with cooler days than nights.

4/30/2019 10:43:08 PM

North Pole,Alaska

bnot,
You gave me the umol readings from your CMH at 8" and your LEDs at 6". can you get me readings at twice each of those distances so I can run some numbers on the dropoff rate? Also if you can give me an idea of current plant height and expected final plant height, we can customize a little more. For tomatoes, once you know the height of the pollinated tomato, you can concentrate the light around that area to help strengthen the Sink.

4/30/2019 10:52:23 PM

Here is the article talking about this. Under year round vegetable growing.

https://www.greenhousecanada.com/structures-equipment/lighting/the-latest-on-lighting-32145

5/1/2019 4:41:06 AM

Oak Grove, Mn

dave....i am going to be time tied for a few days...closing on a house is a serious distraction from growing. Found out yesterday...electricity is going to cost me 2 cents more per kilowatt with the provider in the area....grrrr. Might have to do some cost analysis....solar might be on the horizon. I can get you my current spectrums band on my LED's. It will probably be next winter before I am fully into the indoor season again. What year was your last diary entry. I will look for your email there..or you can just email me at bnot1962@gmail.com. Thanks again...takes a special person to solve the difficulties of the indoor environment

5/1/2019 8:21:34 PM