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Micro-plastics in Fertilisers! The Truth About Controlled-Release Fertilisers · Hydroponics Daily

• 0:00
  Hi there, welcome back to Hydroponics Daily, your go-to podcast for everything soilless cultivation.
• 0:05
  You may remember a few months ago, a couple of months ago, I did a podcast about
• 0:10
  why garden centre fertilisers suck and explained the reasons why.
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  Well, I missed one part off because I focused mainly on liquid fertilisers.
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  However, a really big part of the fertiliser offering in many garden centres
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  and retail stores is granular fertilisers, controlled release fertilisers and
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  explain why these can be bad for your plants and for the environment.
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  So on the face of it, they sound great because they're controlled release.
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  They release the fertilisers slowly when the plant needs it,
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  so temperature related, and rather than being one big gulp of fertiliser that
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  could get washed away, it's released slowly over time.
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  However, the big, big problem with these controlled release granules is that
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  they don't biodegrade readily.
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  They don't they're not classed biodegradable the one
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  of the ingredients is vegetable oil but they use that to
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  sort of say oh this is a natural resin however it's that
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  oil is cross-linked polymer and with synthetic
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  chemicals that turn it into a non-biodegradable
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  plastic basically and so if you
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  i've never used these products in my
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  garden at home and yet when i dig the soil up
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  they're there because they don't biodegrade and there used to be a load of pesticides
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  blue pesticides that killed black vine weevil and they got banned so they've
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  not been used for ages and yet you still find them next to like rhododendrons
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  when you dig up a rhododendron the really old rhododendron because the just
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  the plastic granules are not biodegradable.
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  And we're finding out more and more about the health impacts
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  of microplastics and nanoplastics in
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  food and this could be a major contributor is the overuse of these granules
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  people will just throw them around you can also get plugs of them in houseplants
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  so you might leave loads of granules stuck together in like a like a thimble
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  and you poke them into your houseplants to feed them.
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  So the overuse of microplastics is a big issue now in horticulture.
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  So as I say we're learning more about the absorption of nanoplastics and a recent
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  study by the University of Plymouth down on the south coast of England showed
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  that you grow radishes hydroponically in a solution containing polystyrene nanoparticles
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  that were radio-labeled carbon.
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  After five days they examined how far into the plant the particles had penetrated
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  finding that nearly five percent of those originally in the solution have been
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  retained in the root system the part of the plant that you eat,
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  that amounts to millions of nanoplastics entering the
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  crop and then obviously if they're entering the crop they're entering your body
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  as well when you eat them of those particles around a quarter had made their
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  way into the edible fleshy roots while 10% had accumulated in the leaves so
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  if you're growing even if you're growing crops where it's the leaves the leaves
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  or the flowers that you're eating they can still the nanoplastics can still
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  move so that's something to look out for and It's an area of massive issue.
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  So microplastics are also found in tire wear, flaking paint.
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  So it's not just fertilizers that are the issue here, but certainly it's a big
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  contributor and people are willingly putting plastic into their soils and in
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  their growing media and it doesn't need to be the way.
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  You can use alternatives, you can use plastic-free liquid fertilizers, for example,
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  just using little and often is always the best way in
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  horticulture now the companies that manufacture these resin
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  type granules will talk about how you
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  know they'll have a spin on it to say that they are you know used
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  sparingly and they advise all this blah blah blah blah and that the they their
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  vegetable plant origin and things like this however their own internal documents
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  say that they are working actively to work on biodegradable options and that
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  they're looking to come into line with EU,
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  European Union targets for,
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  biodegradable products.
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  And so they fully acknowledge in these internal reports that these products
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  are not biodegradable and that they need to do better.
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  Publicly, on the PR side, they're not saying that, that these products are microplastics
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  that you're putting into your soil, but no one else is sort of calling them
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  out for it, apart from me.
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  So yeah, make sure you spread the word, the likes of Miracle-Gro,
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  Osmocote, their granules are not biodegradable and,
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  you should really avoid them if you don't want to add microplastics to your grow media.
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  At Eutrema, we've experimented with some biodegradable granule type products.
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  However, they are quite expensive to produce.
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  And so we don't make products for garden centers because they're always made
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  to a price point, which is cheap as chips. And we don't make cheap as chips products.
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  So maybe for like sports turf, we might look at granules there for slow release,
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  controlled release products, fertilizers, where they don't have the ability
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  to spread liquids quickly,
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  but not one for hydroponics and not one for home and garden, certainly.
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  Okay, until tomorrow, thank you very much for listening, and it's a short one
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  today because I'm feeling under the weather, but hopefully we'll be back better
• 5:12
  than ever tomorrow. Okay, thanks for listening, goodbye.