Plant Growth at Night

[Starlight]

Originally Posted by Worth1

Nowhere on earth do plants get 24 hours of light.

How about anything above the arctic circle.
The sun stays up all day and night on the north coast of Alaska and many other places.
I have yet to see a wild tomato plant there though.

Worth

Didn't think about Alaska. Dumb question, but when they are having their 6 months of dark or however many months it is, do they have moonlight up there that would still supply light to plants?

Originally Posted by Fusion_power

and you have been spending a few weeks on Alaska's north shore fishing.... Right?

Most lighting systems are based on providing about 25% as much light as full sunlight. C3 photosynthesis saturates about this level. Providing more light than saturation just wastes energy.

trivia - full sunlight is about 2000 mols depending on where you are near sea level or high on a mountain where there is less air to absorb light. C3 photosynthesis saturates around 500 mols. Healthy seedlings can be produced with as little as 200 mols if other conditions are favorable.



If you want to try a regime that produces more growth than 24 hour light, try 20 hours light and 4 hours dark. See what happens.

I think I may give some plants the 20/4 and see what happens. I am curious now too. Always up for trying something different and learning. Now if I try this and my plants grow to fast too soon and I run out of room indoors, I'll send my babies to you and you can babysit them til they can go outdoors and play.

What about moonlight? Does moonlight have any great affect on tomato and pepper growth?

[Worth1]

Originally Posted by Starlight

Didn't think about Alaska. Dumb question, but when they are having their 6 months of dark or however many months it is, do they have moonlight up there that would still supply light to plants?



I think I may give some plants the 20/4 and see what happens. I am curious now too. Always up for trying something different and learning. Now if I try this and my plants grow to fast too soon and I run out of room indoors, I'll send my babies to you and you can babysit them til they can go outdoors and play.

What about moonlight? Does moonlight have any great affect on tomato and pepper growth?

They have moonlight but the plants are dormant and under ice at 30 below zero.
The Arctic circle is the line on the earth where everything gets at least one full day of sunlight or darkness.
As you go north of it you get more days of this.
The sun is also lower in the sky even in the summer than it is here.
It will circle around the horizon.

Needless to say, the Forth of July fireworks display in Alaska leaves much to be desired.

I was in Amsterdam drinking beer one time at a cafe and was wondering when the sun went down it seemed late.
It was 11PM at night.

Worth

[AlittleSalt]

We found a place to try the 20/4 growing conditions. It's a room long forgotten filled with renaissance fair clothing, material that nobody wants, and stuff from yesteryear.

I'll have to remove all the stuff on the floor and do a lot of cleaning. There may be a leak in the roof, but so far, I haven't found obvious signs - other than it smells moldy. First thing will be to get to the window and open it. Then turn on our shop fan for a day or two. I can see tomatoes eventually growing in there.

[Starlight]

Salt... Glad you found a room. Just don't toss to trash the stuff that is there. If you have a flea market near you that stuff can be worth quite a bit of money. You'd be amazed at how much folks buy that stuff and are willing to pay. Give ya more money for soil, seeds and fertilizers and growing stuff. : )

[Worth1]

Originally Posted by Starlight

Salt... Glad you found a room. Just don't toss to trash the stuff that is there. If you have a flea market near you that stuff can be worth quite a bit of money. You'd be amazed at how much folks buy that stuff and are willing to pay. Give ya more money for soil, seeds and fertilizers and growing stuff. : )

I found a whole pile of China made in Japan for 99 cents a piece at Good Will the other day.
On line the same manufacture and pattern was going for $12 a piece.
Unfortunately I wasn't in the market for the Manufacture or the pattern.
I am looking for the Onion/bulb pattern made by Meissen.

Worth

[AlittleSalt]

Originally Posted by Starlight

Salt... Glad you found a room. Just don't toss to trash the stuff that is there. If you have a flea market near you that stuff can be worth quite a bit of money. You'd be amazed at how much folks buy that stuff and are willing to pay. Give ya more money for soil, seeds and fertilizers and growing stuff. : )

Star, I was careful not to call it all junk
It is honestly far from it. All the renaissance fair costumes were made in the sewing building near this room by my stepmother and wife. I have to get them out of that room and let them air out. My grandfather's LPs and lots of disability equipment is also in there. We have a week forecasted without rain, so I'm hoping hanging the clothing out on the clothesline will air them out enough.

It will be a long trip down memory lane going through the stuff in that room.

We will have to fix the roof or wherever it is leaking. We already have plenty of shingles and roofing nails. I wish I could still get up on the roof to fix it myself, but there's plenty of help to get it done. I will probably go ahead and replace all the electric outlets as well. Maybe a coat of paint or two.

[Cole_Robbie]

Did those plants really grow overnight, or did they just stretch?

The intensity difference aside, sunlight also contains UV, and the "rest" that plants need at night may relate more to getting rest from UV radiation than from actual light.

We've had the light hours debate before. I don't think there is a definitive answer. The "rest" mechanism has been noted in fruiting outdoor plants under the sun. However, there is also a study that showed an increase in yield under 24-hour light for indoor plants. That increase was small, and not enough to justify the extra electricity usage, but it did exist.

My early spring seedlings are always started under 24-hour light. If I'm wrong in doing so, I think the end result will be just wasting electricity, and not any damage to the plants. Another way that it helps me is in making it easier to maintain a warm environment. Otherwise, I'd need a heater, which would probably make my humidity levels drop and everything would dry out too much. It's a lot easier to just leave the lights on and have the lights do double duty in providing heat, too.

[kurt]

I just posted this on another thread.Some more background info.

http://tomatosphere.org/teachers/gui...ants-and-light