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Allelopathy: The Hidden Plant War · Hydroponics Daily

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  Hi, welcome back to Hydroponics Daily. Today we're talking about allelopathy,
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  or allelopathy, however you want to say it.
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  I know that pathy means death or disease.
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  I've no idea what allelo means, so drop a comment if you know.
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  It's a phenomenon that occurs when you grow plants together,
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  normally of different species.
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  This is important because a lot of people now are doing living soil type grows,
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  or they're mixing grasses below other crops and things like this.
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  It's also important in gardening, and things like this
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  where you you'll find a negative interaction between different crops
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  or multi-cropping on farms where
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  they've started to grow two crops together so like
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  near here there's a there's a research trial where they're growing
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  boats which is barley and oats together.
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  And you get positive interactions like you
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  know the nitrogen being absorbed by the
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  beans and then you get negative interactions which are
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  allelopathy so this can be scientifically
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  shown where you grow plants of two different species in separate
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  pots and they grow really well but if you were
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  to grow them together one or maybe both of them
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  will their growth will be impeded and that's because the
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  chemicals released by one of the plants to harm the
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  other plants to out-compete them so they produce a
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  natural herbicide and the classic example of
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  this is black walnut or juglans nigra
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  and this releases a chemical called juglone which
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  sounds like a like a rat band from south
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  of america i'm sure there's something like that the juglones or something
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  like that anyway it's a chemical i think it's an alkaloid and
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  it's released from the roots of the black walnuts and juglone
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  stops a lot of plants from growing underneath black
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  walnuts so you see a walnut plant often you won't see
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  plants growing underneath it pines are another example where
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  allelopathy is thought to occur however the situation
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  is complicated by the fact that if you think of something like a
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  pine forest it's going to be very dark and dense
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  there's going to be lots of roots in that system and so whether it's just competition
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  for nutrients water and light or is it actual chemical inhibition that's occurring
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  is hard to say either way certain plants don't grow well together and that's
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  because of allelopathy which has been hydroponics daily for today.