When do plants grow the most?

[monty67]

Might seem like a dumb question but is it with the lights on or with the lights off?

[ADJAquariums]

theres really no such thing as a dumb question. PLants grow the most when the lights are on in the tank, and minimal to no growth at night, these changes are noticeable in certain plants ecspecially, i see it the most in my wisteria, in the morning when i turn on the lights i see how tall the plant is compared to things around it, and when i turn off my lights i look again and i truely notice differences in the hight of the plants from day to day

So in the short version they grow when the lights on

[monty67]

cool, thanks.

[oscarsx]

In my experience, Plants grow when the lights are off.. that's my own experience.

[chad320]

You are the winner of the interesting question of the day. I have kept plants for years and never really remember considering this question. I do know that plants respond to hours of uninterrupted darkness as opposed to light for seasonal changes.

[@marko@]

id imagine its equal for both. glucose is made and stored during the day, and then used from those stores at night. the intracellular concentrations of glucose, nucleotides, amino acids, ATP, etc. should remain fairly constant throughout the day, so cellular growth and division should happen all the time as long as nutrient input is adequate.

[monty67]

See, I had heard that it was at night and that's why I asked. I always thought they built up reserves of energy during the light hours and used it during dark. Now I wonder if it's not dependent on individual species.

[Darkblade48]

I would also say that plants are growing all the time.

There are a set of reactions known as the dark reactions, but this does not imply that they only occur at night. They are more accurately known as the light independent reactions; essentially the plant uses the glucose it has stored up from during the day (when photosynthesis was performed) and uses them to continue growing.