can you have too much light

[kycountryboy]

i built a box with reflective insides. i started tomato seeds 6 days ago. they are already 2 " high and sturdy. i am using 8 bulbs on 32 w 6500k. i have extra light fixtures and was wondering about adding 1 more light. i have 6 trays 3 wide 2 deep. this will have all lights fixtures about 1 to 2 " apart. my question is can i have too much light.

[gssgarden]

I would think you have enough. I don't even think the reflective sides are needed.

As long as you give them plenty of 'rest' at night, I'm sure they will do fine.

Greg

[kycountryboy]

how much off time do you suggest.

[paulgrow]

I do 12 hours on 12 off

[rags57078]

Originally Posted by paulgrow

I do 12 hours on 12 off

I do this also

[gssgarden]

at LEAST 10 hrs of dark a day.


Greg

[brianccarr]

What would be the result of leaving the lights on to long? My timer broke and the lights ended up staying on 24 hrs a day. I've has poor results and I am trying to figure out what went wrong.

[Worth1]

16 on and 8 off.

Worth

[rags57078]

Originally Posted by brianccarr

What would be the result of leaving the lights on to long? My timer broke and the lights ended up staying on 24 hrs a day. I've has poor results and I am trying to figure out what went wrong.

They will get stressed , yes I have had it happen

[kycountryboy]

thanks set timer for 16/8 off

[Hermitian]

Originally Posted by kycountryboy

i built a box with reflective insides. i started tomato seeds 6 days ago. they are already 2 " high and sturdy. i am using 8 bulbs on 32 w 6500k. i have extra light fixtures and was wondering about adding 1 more light. i have 6 trays 3 wide 2 deep. this will have all lights fixtures about 1 to 2 " apart. my question is can i have too much light.

To answer your question requires two measurements:
What is the projected area of the light?
What is the total wattage of the 6500 kelvin bulbs in use?

From that, you can compute watts per square foot. The optimal range is 55 W/sq.ft. to 75 W/sq.ft.

For tomatoes and Solanaceae in general, you risk tasking resources of water and food above 75 W/sq.ft.

In this range, 12 to 16 hours of light is sufficient.

[Cole_Robbie]

Originally Posted by brianccarr

What would be the result of leaving the lights on to long?

It looks like I'm going against the crowd here, but I say nothing. Tomato seedlings do just fine in 24-hour light. They don't need dark until 7-8 weeks. I raised all my seedlings under 24-hour light before I got my greenhouse, and they did just fine. Pepper plants seemed to prefer it; the tomatoes might not care either way, but it did not hurt them in any way that I could see. I sold a lot of the plants and grew the others in the garden.

[creister]

16 on and 8 off. Need dark for the dark cycle of photosynthesis which I also believe is called the Krebbs cycle. Some one correct me if I am wrong.

[creister]

Krebs cycle is not dark cycle sorry my old memory fades. But plants have a dark cycle in their processes of energy use and production.

[Worth1]

Originally Posted by creister

Krebs cycle is not dark cycle sorry my old memory fades. But plants have a dark cycle in their processes of energy use and production.

That's not true in all cases.
On my home planet we have two suns and 'whoops---------------.

Sorry never mind, this isn't the intergalactic gardening forum.
I think the cats outta the bag.

Worth