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Autoflowering vs Photoperiodic crops · Hydroponics Daily

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  Hello, welcome back to Hydroponics Daily. Today we're going to talk about a
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  subject that's very important to hydroponics and that's day-neutral versus photoperiodic plants.
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  Day-neutral is also known as auto-flowering, so these plants flower regardless
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  of the length of the daylight that they receive or more critically the length of the night.
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  And so day-neutral plants will flower after
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  a certain number of weeks growing in your grow environment and
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  for some crops you'll get day neutral or
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  auto flowering varieties or strains and for
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  others you'll get photoperiodic ones and some people prefer day
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  neutral because that fits into their grow environment some
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  people prefer photoperiodic because they can control
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  exactly when they switch from vegetative
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  growth to flowering also some people say that
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  the products produced the yield the
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  harvestable crop might be better in one rather
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  than the other due to variety of genetic issues so
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  as i say there's some you often talk about day length or photo period but it's
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  not the day length that's actually the critical point it's the night length
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  that's important and that's because in the plants all plants have this pigment
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  called phytochrome so So not chlorophyll,
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  that's another pigment, or it's phytochrome.
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  And that absorbs red light during the day.
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  And then when it goes into darkness, it converts back into another form.
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  And how long it's converting back tells the plant how long it's spent in night and day.
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  And so if you flashlight a plant during the night, it'll think it'll reset its phytochrome.
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  So it's the length of the night that's been found to be very important.
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  So some plants are long day plants and they flower when the day lengths get
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  long and the nights are short and others are short day plants that flower when
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  the days are shorter or shortening.
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  So example would be lettuce is a long day plant and others are short day plants.
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  So you use this, you find out what your crop is and then you adjust the day length.
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  So you might be growing for a short day plant, you might be growing in 18-hour
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  day lengths when you're trying to keep them vegetative, and then reduce that to, say, 12 hours.
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  Now, how much you reduce them by or increase them by is based on something called
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  the critical day length.
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  And that is the amount of time it has to be spent in day and night in a 24-hour
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  period. And that's critical.
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  That's critical. So if you go above or below that, that's when they switch from
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  flowering to vegetative and vice versa.
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  And that varies depending on the particular species. Some have critical day
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  lengths of 12 hours. Some have 15, 16.
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  And it can get very complicated. If you look in the research,
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  I did my PhD doctorate thesis on flowering.
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  Flowering in rhododendron and I looked at
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  all the different types of flowering in all the different plant species and
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  you get things like short long day plants that need
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  short days then long days you have
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  plants that need to have a winter period before they can
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  be photoperiodic you have plants that need to grow
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  for many many years before they will respond to
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  photoperiod and they have a long juvenile period other
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  plants like morning glory it's photoperiodic
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  straight away as soon as it's germinated and if you
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  give it the right day length it'll flower straight away hops is
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  an interesting one it's in the cannabis family and hops
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  if you grow it in zimbabwe you have to give it artificial light
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  because it doesn't flower a cup with the day lengths in
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  zimbabwe and so people tried to grow hops for beer production
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  down there and then they they really struggled and the plants wouldn't
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  grow tall either so it's a vine crop
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  and there was really big issues with hops so
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  day neutral auto flowering other things like temperature will.
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  Have more of an effect on how long it takes you to flower in these
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  plants but they will just switch after a certain number of weeks and
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  then these these photoperiodic plants you
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  you can take cuttings from when they're staying vegetative whereas
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  these plants that there's a ticking there are a ticking time bomb you can't
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  take cuttings from them because they're going to be flowering after
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  a certain number of weeks and even those cuttings are going to be flowering after
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  a certain number of weeks regardless of from the point is
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  from the point that the seed has germinated so that's
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  something to consider with day neutral plants and day neutral plants are very useful
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  in growing outdoors if you've
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  got a plant with a long life cycle and you need it to flower on fruit
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  before the frosts and the damp of autumn come in they're really good so think
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  about day neutral plants are really good for growing outdoors whereas photoperiodics
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  tend to be favoured indoors where you've got more manipulation over the grow
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  environment so that's hydroponics daily for today i've probably missed something
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  so if you've missed something really important,
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  comments and i'm sure to include it on another video thank you or podcast.