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Why Ladybirds Fail in Hydroponics: The Truth About Biocontrol · Hydroponics Daily

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  Hello there and welcome back to
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  Hydroponics Daily, your go-to podcast for everything soilless cultivation.
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  Today I'd thought I would talk about ladybirds and why I don't think they're
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  a great biocontrol agent for hydroponics and why I've never got on well with
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  them when using them in hydroponics.
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  Now you can buy ladybirds to use to eat up aphids and other pests in your grow
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  environment and ladybirds get a great press.
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  Everyone loves ladybirds, they look beautiful and
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  you know it's thought they're voracious consumers of aphids
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  they eat hundreds of aphids in their lifetime now this
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  depends so they're a beetle and so
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  they go through a life cycle that starts off as an egg then into a larvae that
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  then pupates into an adult and we've got to remember is that it's the larvae
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  that do most of the eating of the aphids so if you're buying ladybirds you want
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  to be buying the larvae, not the adults.
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  And in North America, you can buy the adults and they're not as good because
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  they just fly away and they don't eat many aphids.
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  They're more concerned about procreating.
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  So that's the first thing. The second thing is the larvae, if you put them in
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  your crop, you sort of put them in there.
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  They don't do much. You nudge them, you know, come on, let's eat some aphids.
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  And a lot of the time they just end up rolling over and dying.
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  Don't know what it is about...
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  Ladybird larvae, but I've never got them to consume aphids in my hydroponic grow rooms.
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  The other thing about the larvae is they're big, and so they can get into filters.
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  Same with the adults, they can block filters and fans and things like this,
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  and decompose and rot, and things like this. So not great from that perspective.
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  They also suffer from sexually transmitted diseases, apparently,
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  and so that can be an issue.
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  There are invasive species of ladybirds that eat other species
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  of ladybird like the harlequin ladybird in the
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  uk that was introduced into a number of countries as
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  a biocontrol agent and then found to be as well
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  as being a easy species to culture was also
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  a species that ate other ladybirds and so destroyed native populations so around
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  arrived in the uk around 2004 and has moved around the uk the british isles
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  since then as well so found throughout the british isles so ireland and great
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  britain and northern ireland,
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  and so that's something to consider when it comes to ladybirds the other thing
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  is that they they do have a set amount they can eat their life cycle is fairly
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  long for a biocontrol agent.
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  What else can we say about ladybirds? There are better alternatives.
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  So I prefer lacewings. I think they eat more aphids.
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  The larvae. So if you want a similar type of organism, then a lacewing is good.
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  Lacewings will give you a nip every now and again, but they are very good biocontrol
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  agents. The adults do fly away, just like ladybirds.
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  So if you're in an outdoor situation or a greenhouse where you haven't got vents,
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  then that's something to consider.
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  They will fly away eventually unlike predatory mites
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  which will stay in your grow room most of
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  the time and often these are better now there
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  are ways to to keep them alive
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  as well mites when when there's when the
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  aphids have run out so you can feed them things like pollen and
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  bran and things like this and flower mites to
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  to feed on whilst whilst there's no aphids there
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  so you can keep a background population whereas lacewings and
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  ladybirds you can't really keep a background population once the
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  pest has been consumed then
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  your your biocontrol agent will die out as well so definitely to consider swirsky
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  mites as an alternative they'll also eat thrips whitefly and spider mites so
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  that's something i prefer so let's have a lacewings let's have a look at some other lists.
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  Parasitoid wasps as well. So parasitic means that they, well,
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  predatory means that they eat predators and parasitoids means that they lay their eggs inside.
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  So a parasite lives inside and a parasitoid lays its egg inside.
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  So a parasitoid wasp doesn't get into the pest, it just lays its egg in it.
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  And there are a number of different species of parasitoid wasps that will kill aphids.
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  The aphidious genus is the most common. And then for whitefly,
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  perhaps the most common is Incarcia formosa, but that's specifically for whitefly, not aphids.
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  So not really an alternative to ladybirds. But definitely look at parasitic.
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  Wasps because they can lay lots and lots and lots
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  of eggs thousands of eggs in thousands of aphids
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  whereas a eventually a ladybird you know
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  more than a ladybird could eat for example and so
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  definitely something to look at there parasitoids and then
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  in certain countries you can get fungi
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  that will attack insects what are called entomopathic fungi
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  certain species are registered in the uk and
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  you can obviously use insecticides bio insecticides
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  insecticidal soaps as alternatives or as
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  part of the biocontrol integrated pest
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  management so to say integrated pest management ipm strategy
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  so be interesting to know
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  your thoughts on the effectiveness of ladybirds and ladybird larvae
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  the other limitation is that there's only a few companies
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  or a couple of companies selling them they might be imported into the uk
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  so that the lifespan of them is
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  might be limited in storage whereas in north america
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  you might have more producers of ladybirds there are
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  some big producers ladybirds and you can buy them in garden centers and
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  things like that whereas in the uk you can't do that and i think ladybirds don't
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  last as long in storage as mites and parasitoid wasps so you know mites will
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  last a long time in the packet and you can keep them alive by feeding them pollen
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  and things like that so that's my take on ladybirds and.
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  And they're used in grow rooms. I think they're a bit crap, and they're expensive
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  because everybody wants them.
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  I suppose they're easy to identify. They're easy to know when they're there
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  and when they're working, when they're alive.
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  Whereas a predatory mite, you struggle to get to see them, and you might confuse
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  them for two spotted spider mite or other plant-eating mites.
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  So there's an advantage there for ladybirds, I suppose.
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  Anyway, that's been Hydroponics Daily for today the pros and
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  the many cons of applying ladybirds in a hydroponic grow
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  room or greenhouse thank you very much for listening if you
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  found this useful please leave an apple podcast review if you're not
• 6:43
  an apple then check out the utreema website even if you are an apple check out
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  the utreema website very very slow day today on sales b2c direct to consumer
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  sales because rachel reeves the chancellor of the exchequer has been in the
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  news and any day that her hair her face is on the news.
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  Sales slow down, everyone closes their wallets. Luckily, our business-to-business
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  sales have been very, very buoyant, so we have been busy today.
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  But yeah, Rachel Reeves, she's not good for the hydroponic sector because she
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  closes everyone's wallets when she appears on the headlines of the news.
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  Hopefully, she'll get off there and some other bad news story will appear and
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  everyone's wallets will open and they'll start buying fantastic fertilizers,
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  biostimulants, and what else do we make?
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  Biopesticides. All right, that's been How to Point It's Daily for today.
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  Thanks very much for listening. Goodbye.