Do 15/9 is enough light time to keep them in veg

Josué69

Member
Yeah im about to plant a weed plant outside but it's winter so i would like to know if the fact that there is less of light in winter can affect my plant ? Can 15/9 put them into early flowering ?
 

bird mcbride

Well-Known Member
If you're budding these plants put them in a closet at in the evening and put them in the sun in the morning every 12 hours. Just fit them in somewhere where they'll get 12 hours of the best available light and in the closet for the 12 hours of darkness,
 

Josué69

Member
If you're budding these plants put them in a closet at in the evening and put them in the sun in the morning every 12 hours. Just fit them in somewhere where they'll get 12 hours of the best available light and in the closet for the 12 hours of darkness,
Thank you mate... I was actualy looking for cfl ligths that work with battery do you know where i can get somes ?
 

bird mcbride

Well-Known Member
Maybe you should check into gas, etc lanterns in you have the facilities to accomodate them. Maybe you can find something in the correct spectrum. We actually do use them but only for added co2 and they work great for power failures when the hps goes out.
 

Josué69

Member
Okok thanks
Maybe you should check into gas, etc lanterns in you have the facilities to accomodate them. Maybe you can find something in the correct spectrum. We actually do use them but only for added co2 and they work great for power failures when the hps goes out.
 

dirtpower

Well-Known Member
In theory they need minimum of 13 hours of light to stay in veg.
That would depend on weather it's Ind or Sat or even a blend I once had a Sat the refused to flower until the lights hit 10.5 hr and have had ind start flowering at 14...so I think 15 is the lowest one could go and stay in veg.
Sorry about abbreviating Ind and Sat, but my spelling sucks and can't get it close enough to look good
 

yahooman

Active Member
As long as you give them 13 hours of light.
thats not true at all....just because growers use 12/12 doesnt mean a plant wont flower at 13/11..

the key is to match the daylight hours when you put them out...for example:say june 1st at 45n the sunrise is 5;45am and set is 9
;30pm,thats 16 hours and 15 minutes,plus i add 1/2 hour of twilight so ill do 16.25 hours....put my lights on at 5;30am and off at 9;45....

those hours are not exact,just an example
 

Vnsmkr

Well-Known Member
Finishing times, Photoperiod, Latitude, and how it all works!!
We all know the basics of vegging and blooming Cannabis..... when the day is long and the night is short the plant concentrates on vegging(growing), when the day length shortens enough, the plant starts to bloom.

But how does all this work?
Why does the same strain finish at different times in different parts of the world? Does 12/12 really mean anything outdoors? Why is Latitude(or "Lat") so important to some growers? What is a "Auto-flowering" plant?

Lets get into the meat of the subject shall we?..............

Photoperiod
The first thing to cover here is Photoperiod- Photoperiodis the ammount of time there is light in a 24 hour period. In Cannabis growing, Photoperiod is typically shown like this- 12/12 or 16/8, or 18/6, etc. The first number is usually the length of the lighted period, the second shows the balance of the 24 hours that is dark.
Outdoors the sun controls the Photoperiod. Its length changes through the seasons according to the movements of the sun in the sky, a matter of fact itcauses the change in seasons. This brings us to......
Photoperiodism
Photoperiodism is the reaction of many flowering plants(including Cannabis) to changes in Photoperiod. Plants that experience Photoperiodism have pigment cells called Phytochrome that monitor the ammounts of light being absorbed by the plants(specificly the red end of the spectrum), and the length of day. Signals from the Phytochrome tell the plant to do many things, including to grow, bloom, and in the case of some trees, to loose their leaves and go dormant in Autum.

Most of these plants fall into three catergories concerning blooming times, that being- long day plants(blooms as day gets longer), short day plants(blooms as day gets shorter), and day neutral plants(blooming is not according to light cycles).
All Cannabis varieties are either "Short day", plants or "Auto-flowering" (known as "Day neutral" outside of the Cannabis community). So called "Auto-flowering" plants do not seem to take their blooming cues from the sun, and thus should be considered "Day neutral", as most seem to be geneticly programmed to bloom according to age insted.

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The Sun, Latitude, and why the same plants finish different times at different points on the globe

The year as we know it is basicly the time it takes for the Earth to make a complete loop around the sun. As the Earth makes this loop it shifts on its axis, so that either the northern half or southern half(Hemispheres) have the longer photoperiod.



The shortest day of the year is called the Winter Solstice, this day occurs on December 21st in the northern half of the world, on the same day in the southern hemisphere they will have their Summer solstice, the longest day of the year. On June 21s it will be reversed, with the longest day of the year in the north(Summer solstice), and the shortest day in the south(Winter solstice).

Two days of the year are known as the equinoxes, one occurs March 21st and one on September 21st. These days represent the halfway point between the longest and shortest days of the year, on these days the day length is almost exactly 12/12 all over the world. If you are in the Northern hemisphere, Mar. 21 is the first day of Spring and September is the first day of Autum, reverse these dates in the southern hemisphere.

Latitude
Latitude is the east-west lines you see on a globe or map of the earth, they are spaced about every 111 Kilometers starting at 0 degrees at the Equator, and graduating north and south from there (every 111 KM) to the north pole(90 Degrees North) and South pole(90 Degrees south).

Here is a link to Wikpedia explaining Latitude-

Latitude

At the Equator the length of day doesn't change much from month to month, at both Solstices the length of day is about 12 hours, at both Equinoxes it is about 12 hours, almost perpetual 12/12.

Now lets take a look at Portland Oregon, this city sits near 45.4° N, which is about exactly halfway between the Equator(O°) and the North pole(90°N).
At the Winter solstice, the length of day is 8h 41m, at Summer solstice the day length is 15h 41m, and at the Equinoxes it is 12h 12m.

And now lets look at Anchorage Alaska, this city sits at 61.2° N, a little over 2/3 of the way to the North pole(90° N) from the Equator(0°).
At the Winter Solstice the day length is 5h 27m, at Summer solstice the day length is 19h 22m, and the Equinoxes are 12h 18m.

As you move away from the equator(either north or south), you see more distictness between the seasons and the length of days during those seasons.
Generally the closer you are to the Equator, the less difference there is between the length of day on the Solstices(the longest and shortest days of the year.
The further you are from the Equator, the more difference there is in length of day between the Solstices, making the Summer shorter and shorter, and the longest day of the year longer and longer the further you go from the eternal 12/12 of the Equator.

Here are the Latitudes for a few North American, European and Australian cities to show a example of the vast differences in latitude-

Darwin, Australia-12.4° S
Miami, Florida-25.8° N
Houston, Texas-29.7° N
Los Angeles, California-34.1° N
Atlanta, Georgia-33.9° N
Canberra, Australia-35.3° S
San Francisco, California-37.8° N
Reno, Nevada-39.5° N
Naples, Italy-40.8° N
Chicago, Illinois- 41.9° N
Boston, Massachusetts-42.4° N
Toronto, Ontario-43.6° N
Ottawa, Ontario-45.3° N
Seattle, Washington-47.6° N
Vienna, Austria-48.2° N
Vancouver, British Columbia-49.2° N
Calgary, Alberta-51.1° N
Warsaw, Poland-52.2° N
Amsterdam, Netherlands-52.3°
Edmonton, Alberta-53.3° N
Anchorage, Alaska-61.2° N

Here is a thread with a list of US cities and their latitudes- List of longitude and latitude coordinates for North America

The Photoperiod sensitive strains of Cannabis are each geneticly programmed to start blooming when day shortens to a certain length*.
When these various strains are bred, they become acclimated to that latitudes photoperiod, they are bred to bloom and harvest before that areas climate becomes too cold and dark(or wet), usally to avoid major mold problems, or harsh freezing weather.
*Many experts agree that it is actually the length of the dark period that matters to plants.

When you take a plant that was bred in one location, and move it to a similar Latitude, say from 42° N to 43° N the plant should harvest at nearly the same time. But if you take a plant from 42° N to 50° N, its possible that the plant may not harvest early enough to beat Winter further up north.
 
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