Light Duration / Photo Period

[mbsqw1d]

hi all.

i am having one of those moments where i need to ask a possibly stupid question...

Do plants, know what time of day it is?

I mean, if you were out of your house 9 - 5 and you needed to illuminate your plants for 6-8 hrs. Then would say 6pm - 12am be an option? or are plants somehow hardwired into nature that they automatically follow the time of the sun and therefore only grow during the afternoon?

thanks for commenting on my possibly stupid question

 

[SuperColey1]

What a stupid question . Kidding.

A chap I know who is a gardener by trade (....Doh) was trying to tell me about plants having biological clocks the other day that control all their behaviours.

Now I am a little bit cheeky and do like a little bit of a pub debate. Having such a big nose this isn't so wise because it means even the shortest of reaches is negated by the proximity of my hooter but I cannot break this bad habit. lol

I suggested to him this was a load of old tosh and of course like a Carp spotting a nice juicy prawn he bit within seconds.

He stated confidently 'Plants know what time of day it is and what time of year it is.

I replied to him 'Then how come plants come out earlier some years and later in others. If they have a clock then why does the weather dictate what they do. That would mean it is not a clock at all. It is the conditions that dictate.'

I think you've guessed the answer already but I shall continue.

'No, no, no' he said 'Their clock tells them they are ready and they wait for the conditions before acting upon the clock.'

What a load of Codswallop I said and got a faceful of spit from his now increasing anger.

'You are telling gme that if I have plants in a greenhouse where the conditions are right and then black out all the glass so there is no light and then run lights through the night and not in the day that they will try and grow during the dark period due to their 'biological clocks'

The red mist was descending on him more and more and I think all that thinking sent his already beer fuelled brain over the edge. I couldn't understand his speech anymore due to the rage and he reminded me of the Farmer in Shaun the Sheep.

Therefore I left the poor gardener in peace to calm down and get back to his 'Ooh Arrs' although no doubt he was probably calling me Beelzebub all the way home. lol

Another successful night for my hooter with another blemish free outing.


Oh yes......... My photoperiod is 2pm to 11pm. Plants do fine. lol

AC

 

[lljdma06]

I wonder about you sometimes, I really do...

OP, seriously, he's right. I've kept some pretty funky photo periods in my time.

 

[coldcazzie]

What a stupid question . Kidding.

A chap I know who is a gardener by trade (....Doh) was trying to tell me about plants having biological clocks the other day that control all their behaviours.

Now I am a little bit cheeky and do like a little bit of a pub debate. Having such a big nose this isn't so wise because it means even the shortest of reaches is negated by the proximity of my hooter but I cannot break this bad habit. lol

I suggested to him this was a load of old tosh and of course like a Carp spotting a nice juicy prawn he bit within seconds.

He stated confidently 'Plants know what time of day it is and what time of year it is.

I replied to him 'Then how come plants come out earlier some years and later in others. If they have a clock then why does the weather dictate what they do. That would mean it is not a clock at all. It is the conditions that dictate.'

I think you've guessed the answer already but I shall continue.

'No, no, no' he said 'Their clock tells them they are ready and they wait for the conditions before acting upon the clock.'

What a load of Codswallop I said and got a faceful of spit from his now increasing anger.

'You are telling gme that if I have plants in a greenhouse where the conditions are right and then black out all the glass so there is no light and then run lights through the night and not in the day that they will try and grow during the dark period due to their 'biological clocks'

The red mist was descending on him more and more and I think all that thinking sent his already beer fuelled brain over the edge. I couldn't understand his speech anymore due to the rage and he reminded me of the Farmer in Shaun the Sheep.

Therefore I left the poor gardener in peace to calm down and get back to his 'Ooh Arrs' although no doubt he was probably calling me Beelzebub all the way home. lol

Another successful night for my hooter with another blemish free outing.


Oh yes......... My photoperiod is 2pm to 11pm. Plants do fine. lol

AC

love it!!

My photo period is 3.30pm - 10.30pm

 

[JoshuaA]

Perhaps we should start a poll to find out what times people have their lights on? I was wondering what the average user on this forum has their light on. Now winter is closing in quickly I notice the tank much more on a night time, much less when the light is off so I've began slowly transitioning by an hour each week until my light goes off some time 12pm-1am. As it usually turned off at 8pm.

 

[SuperColey1]

My personal goal (no it wasn't to disprove any bilogical clock theories) was that I like to see the tank in the evening.

So while I was working I had the photoperiod 4pm to 12pm. Then when I lost my job I moved it down to 3pm - 11pm because I got bored waiting for the lights to come on.

For the same reason I then extended to 9 hours and set them to 2pm to 12pm.

In thoery I have lights on 24 hours as I have the moonlights timed to turn on 1/4 hour before the main lights turn off and then they turn off 1/4 hour after the main lights turn on. 24 hour viewing

AC

 

[ian]

I work odd shifts, so I get days off all over the place, I also like to see my tank in the daytime, mine are on from 14:30 - 22:30. I would extend that by half an hour but there's
no point, as we are all normally in bed for 22:30 as we have a little one that gets up at 05:00 every morning.

Plants will get used to tikes of light within a tank, getting back to the original question, plants do have clocks (not a clock but IMO a seasonal colck) however we change the way that clock works. Sometimes
we exaust plants, take certain Aponogetons, some of theses need a 2/3 month rest period.