Flipping 12/12 schedule around...a diferent kinda of question Rep given

If i was running 12/12 6am to 6pm
and i wanted to change it to 6 pm to 6am

How would i go about changing the schedule without hurting flowering plants?

This can be tricky , how far into flowering are you?


If you are past 4weeks i would adjust 1 hour every 1-2days until you reach your time.

If you are earlier than 4weeks then adjust an hour every 2-3days as they are still transitioning and susceptible to extreme change.



J

I would just let them run an extra 12hrs. dark and flip the lights back on. It will cause an increase in the budding hormone. Missing 12 hours of light isn't going to harm them. That's how Ive done it in the past.

The easiest way and one which causes the least loss of yield is to give them a 24 hour dark period.
I understand totally what Jondamon is suggesting but there have been studies done which suggest that by giving 13/14 hours of either day or night for an extended period (more than 1 or 2 days) can cause a 20% loss of yield.
The 24 hour dark period, especially if later in flower funnily enough can actually increase yield since the plant thinks it is coming to the end of its life sooner than it expected so it can increase resin production. This is the way I have done it when ambient temps have got too hot for lights on in the daytime and I have never lost yield or had one go hermie on me for this reason.

As with most things to do with growing, you will hear differing opinions, most of which sound plausable. Your "job" as a grower is in deciding which you believe is most beneficial to your plants.

Green mojo dude, W

I did this as well to have my lights on at night instead of day to keep the temps down.

I just gave them an extra dark period and did it all in one shot. I contemplated adjusting incrementally, but that would just take too long, and thsoe damn timers are already backwards anyway.

Glad there are people which have done this to give an answer based on experience.
My answer was based on how "I" would choose to do it.

As for the extended day periods this shouldnt effect very much as you would still be giving the plant 12hours of darkness, Woody have you got any links i can read about those studies?

In the advanced cultivation area on RIU there have been threads playing around with 48hour day cycles 36on 12off. So i'd love to read those studies you commented about (not being funny i would like to read them.)




J

The only thing "wrong" with jondamon's approach is it's a pain in the ass (arse in the UK) relative to just going 24 hours dark. I'd go with 24hr dark period for the sake of simplicity, and wouldn't worry about the minimal effects if any.

3 weeks in.

The easiest way is to go dark for 24 hrs and make the change. One little bump like this the plant will not even notice.....

jondamon said:

As for the extended day periods this shouldnt effect very much as you would still be giving the plant 12hours of darkness, Woody have you got any links i can read about those studies?
J

Click to expand...

http://www.mellowgold.com/grow/mjbotany-removed/
Excellent read
There are others but I dont have links available for them.
W

woodydude said:

http://www.mellowgold.com/grow/mjbotany-removed/
Excellent read
There are others but I dont have links available for them.
W

Click to expand...

Woody This is a very good read but i could not find any information regarding the loss in yield you talked about. It also only talks about Lattitudes and day lengths for growing outdoors so not really viable when contemplating the 48hour day cycle INDOORS.

If you fancy a read try googling 14/12 lighting schedule to get you started.

It isnt the Day length that effects the flowering it is the darkness period. So all you do is trick the plant into thinking that the days are 48hours long in total still with a 12hour dark period to keep it flowering.

Alot of poeple are under the misconception that day lengths are what matters where as its actually the Darkness length of the photoperiod that forces flowering.


J

Just give them a longer dark period, so they don't go into reveg. Shouldn't happen that fast anyway IMHO, people freak out too much.