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Salicylic Acid in Hydroponics · Hydroponics Daily

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  Hi, welcome back to Hydroponics Daily with me, Dr Russell Sharp.
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  Today we're going to talk about salicylic acid.
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  So salicylic acid is a plant hormone and its derivatives are termed salicylates
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  and it's got the name salicylic acid because it was first extracted from willow,
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  which has got the Latin name salix. A lot of people know that.
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  It's also found in wintergreen, I think there's another plant that's found a
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  lot of salicylic acid in, and in the roots and the bark of those plants.
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  So a lot of organic remedies include
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  the use of salicylic acid from extracted from willow
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  and minter green and things like that and so it's it's a
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  natural compound you can also make it synthetically and it's it's a plant hormone
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  that's involved in defense so when attacked by a pest or a pathogen salicylic
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  acid is released and that it primes a number of processes,
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  specifically the systemic acquired resistance or SAR chain of events.
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  Now, there are a lot of chemicals that you can apply to plants that will turn on defences.
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  Salicylic acid is a good one because it's systemic. It'll move around the plant,
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  whereas things like seaweed extracts or chytosan, it won't move around the plant.
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  It'll just stay where it is.
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  So salicylic acid, you can buy products containing salicylic acid and all plants
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  will contain it and it will be turned on when they're attacked.
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  Now, virus attack, if your plant's attacked by a virus, then salicylic acid,
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  you get a burst of salicylic acid that travel around the plants and turn on
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  the defences to stop the spread of a virus.
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  A number of you hydroponic growers have got that problem with viruses,
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  and salicylic acid will be helping minimise their spread in the plant.
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  However, once you've got a virus, I wouldn't advise applying salicylic acid
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  as a synthetic or as a foliar.
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  I I would say just get rid of your plants and sterilize all your tools and clean
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  out your grow room because viruses are nothing to mess with.
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  You can't ever cure a virus.
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  You can only limit its spread and destroy it.
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  Another related compound is methyl salicylate and that is a gas and plants release
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  this and it can travel between plants a bit like ethylene and turn on defenses.
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  So if you remember the film The Happening from 2008, that was a science fiction
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  film where these volatile chemicals were released from plants under attack and they,
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  attacked humans in that case that were attacking them and so that was the basis
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  of these sorts of methyl salicylate based compounds airborne neurotoxins it's
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  not something that actually occurs in real life so don't worry about that there's
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  some plants as i said so it's meadow sweet not met to the plant i mentioned
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  that contains a lot of methyl salicylate,
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  there's another plant called galtheria that's another one that produces a lot.
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  And there's no synthetic inhibitors of salicylic acid and
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  there'll be any reason to produce them but you know a lot
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  of hormones there's inhibitors of them so it's not
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  it's not one of these hormones that's used in when you when
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  you think of hormones and growth regulators salicylic acid
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  is not one of those it's related to aspirin but
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  it is acetyl salicylic acid so that's why
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  when you a lot of people say spray your
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  plants with a dilute solution of aspirin it's because you'll
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  get a similar response to as if you were spraying them
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  with salicylic acid now salicylic acid is also
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  used in skincare it's used in acne cream it's a skin irritant so it's sort of
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  chemical skin abrasion that's one of the problems we have with google ads is
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  that we sell a salicylic acid concentrate we've got the most concentrated salicylic
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  acid product in solution for using like arable crops.
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  But if you run a Google ad, you just get people, mainly women,
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  who want to do this sort of chemical skin burn.
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  It sounds horrific. It looks horrific. It is pretty horrific.
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  And they put salicylic acid in very high concentrations onto their skin and it burns them.
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  And then we had some green keepers up in Scotland and they thought,
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  oh, well, salicylic acid is a skin irritant.
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  Maybe we could take salicylic acid and put on very high
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  concentrations and irritate worms on
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  greens in golf and so some people do that but it's
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  not something we advise if we did we'd be in trouble
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  with various organizations because one of
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  the key things when it comes to pesticides and plant health
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  products is that you must not harm bees and worms so even if you had a product
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  that controlled worms you'd never be able to commercialize it because you have
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  to prove it doesn't harm worms it's a catch-22 so if you were growing hydroponically
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  what would be the use of salicylic acid and you could potentially use it to.
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  Improve the secondary metabolites that produce during
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  flowering and fruiting so sort of the flavor taste compounds it's
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  an as it induces defenses chemical defenses of
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  the plant a lot of these chemicals that are involved in flavoring and taste
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  are the same chemicals used in in in defense and they're not on all the time
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  because the plant wants to obviously minimize the resources it uses in creating
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  them and so it produces under the bare minimum so you go on and produce activate the defense compounds,
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  then you can potentially get more of these flavor taste compounds in your crop.
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  Aspirin has a long use in, so acetal salicylic acid has a long use in promotion
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  germination of certain seeds, hard to germinate seeds.
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  And I guess salicylic acid will have a similar effect, probably a better effect
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  because it's a closer lock and key.
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  We use the phrase lock and key in chemistry a lot.
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  Aspirin will be like a key that works some of the time and salicylic acid will
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  be a key that's designed to fit that lock because that is the actual chemical
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  that is a plant hormone and is involved in plant defences.
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  Just like I've mentioned in the past, Viagra can be used to prevent wilting in cut flowers.
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  Aspirin is another and salicylic acid can be used if you put a bit of aspirin
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  in your vase when you get cut flowers.
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  It can also help with wilting and preventing petal drop.
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  How it does this is a bit long-winded. It's thought that the
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  salicylates inhibit the action of auxin
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  hormone which in turn inhibits ethylene
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  so without without the salicylates
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  the auxin would promote ethylene but i'm not sure a lot of research has been
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  done into it when it comes to cut flowers there isn't much research that's done
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  at all really but i say it could be an interesting one if you're in flowering
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  and fruiting and you're looking for something to promote flavors other than
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  the usual sort of pk boosts and stuff like that, sugars,
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  certainly something I would play around with. But yeah, you want to know more, get in touch.
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  We sell salicylic acid concentrate if you want some. I think there's a couple
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  of products that contain salicylic acid that are out there at the moment.
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  I think BioGreen might have one in the UK, but don't quote me on that.
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  As I say, we produce a highly concentrated just salicylic acid product on its own, standalone.
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  And if you're in the US, I have no idea where you would go for salicylic acid,
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  but I'm sure there is a supplier. You can buy the pure form and try and dilute it.
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  That's been Hydroponics Daily for today. Salicylic acid.