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Whiteflies Part 1: Protect Your Grow · 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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  I'm your host Dr Russell Sharp and today's episode is a pest.
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  However it's not a pest that is common in indoor grow rooms.
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  In fact if you've got it in an indoor grow room you've
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  done something seriously wrong and that's because we're talking
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  about whitefly today and whitefly are not
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  a pest of grow rooms because most inlet
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  filters will will stop whitefly
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  from getting in they are one of the larger pests
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  and so if you've got this in your grow room then you really need
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  to have a look at your inlet filters inlet filters
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  are nothing special they're not like
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  outlet filters they've got carbon activated carbon in
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  them they're just could be a a ripped up piece of
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  old tights or just a piece
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  of small filter fabric filter
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  so nothing major and then as long as they're
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  of a good pore size they'll stop whitefly
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  from getting in things like fungal spores
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  can still get in and some things like a thrip a very small thrip could still
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  get in or a mite but whitefly are normally excluded so this is a pest whitefly
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  normally of greenhouses polytunnels and also outdoors and some plants they love
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  and some plants they don't really affect.
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  So we'll go into what whitefly are and which plants they cause havoc on and talk about them.
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  So they're not, the first thing to remember is they're not actually true flies.
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  Whitefly are closely related to aphids and mealybugs if you've ever had them or scale insects.
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  So when it comes to treating them you will treat them very similar as you would an aphid.
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  In hydroponic systems especially those in greenhouses whiteflies can multiply
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  rapidly and you can have infestations and these infestations can be a national level.
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  I think about two years ago in the UK there were loads of whiteflies that were
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  coming in to the county I live in Northamptonshire from Essex and so they were
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  coming in on the wind of horticultural and agricultural crops and they can get
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  to massive levels if their growth is unchecked.
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  They feed by piercing plant tissue and sucking the sap, which weakens the plant,
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  stunts its growth and reduces yield.
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  And on top of that, their honey juice excretion encourages the growth of sooty
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  moulds, black fungus, so you could get things like bud rot and other things,
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  which further reduce the.
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  The desirability of your crop and they also inhibit photosynthesis
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  so it's a really interesting one they mostly
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  so when you find them you often find
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  them because when you brush past a plant they'll fly
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  off they're one of the few pests that actually when disturbed
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  will fly off an aphid won't do that so the first
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  thing you're looking for is small white moth-like insects
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  so they're not moths they sort of look like a moth and
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  they fly upwards in clouds when disturbed so you may notice
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  sticky residue on leaves black mold on the
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  lower leaves and early detection is critical like with
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  any other pest for proper controlling so as
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  i always say don't if you're growing in cocoa or soil don't
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  water your plants daily but do check your plants for pest and
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  disease daily so monitoring is critical yellow.
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  Sticky traps will also be a good way
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  of finding white flies and controlling white
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  flies so you'll find them stuck to white to your yellow sticky
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  traps so have a look at your sticky traps if your sticky traps
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  are covered in insects put fresh ones up so you
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  can monitor the levels are currently in there don't just have dead decaying
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  insects covered yellow sticky traps up in
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  your grow room it's not good you can introduce biological
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  control if you're in a greenhouse in a polytunnel not
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  really going to work if you're outdoors because they'll just fly off so the
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  parasitic wasp and carcia formosa it's
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  probably one of the model insect species when it
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  comes to biological control very very
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  effective at controlling whitefly it's it's
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  a parasitoid so it lays its egg inside the whitefly and then um that eats its
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  way out like the film alien or the new series alien you've seen that on disney
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  plus it's pretty good ladybirds will eat white flies but i'm not the biggest
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  fan of ladybirds they get caught in outlet filters the adults don't really eat much,
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  and while the.
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  The larvae will eat often they'll die as
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  well quite quickly so ladybirds it's
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  a tricky one i prefer parasitic wasps myself important
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  to get the right species of parasitic wasps they can keep whitefly numbers
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  down without the use of chemicals there's a
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  number of cultural practices that will control whiteflies so they
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  thrive in warm stagnant conditions so increase the
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  air circulation get them moving flying around and
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  then they'll get sucked into the filters and removed humidity
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  make sure you've got the right humidity make sure it's not too dry remove
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  plant debris and clean surfaces regularly will help with white
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  fly control making sure there's no eggs running around
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  on dead plant material as i say a fine mesh screen
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  if you can obviously in most growth growth
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  tents should have that already on your inlet filters or
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  in the in the vents if you're in a greenhouse you can also set up
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  mesh screens you'll see them on
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  commercial greenhouses they don't just put air let air
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  in without filtering it and it looks like a what's
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  that musical instrument an accordion they're called accordion filters
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  and so when the when the the vents of the greenhouse open the accordion filter
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  opens and that stop that should stop whitefly from getting in and then worse
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  comes to worse then you can use chemical control so you need to use a selective
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  insecticide use them sparingly rotate them use different ones at different points
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  so that you don't build up,
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  resistance in the population if you can't fully kill all the white fly in one go.
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  Remember if they keep coming back then you need to cycle out different chemical controls.
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  Remember the chemicals can harm the beneficial insects often more than they can be.
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  The pest. So you need to make sure that you aren't just killing all your biological
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  control and making the situation worse.
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  And you want to look for an insecticide, but obviously if you're going to harvest
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  the crop, you may or may not want a systemic insecticide.
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  If you're growing ornamental plants, then a systemic insecticide is fine.
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  If you're going to have something you're going to eat or smoke or consume,
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  put it in a drink, beverage,
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  then you might not want to use a systemic insecticide so but the
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  good news is that lots of the chemicals and lots of the options even the organic
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  ones insecticidal soaps are a great one for whitefly they'll kill them anything
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  that kills an aphid will also kill whitefly so insecticidal soaps will probably
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  be my best bet because they are safe to consume the crop straight after using
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  them as well so that's a good one,
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  basil crops they are very prone to that so they can be cured by us by a a,
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  a combination of the methods i just mentioned increasing
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  air circulation releasing in carcia formosa and
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  either horticultural oil sprays or insecticidal soaps and so you can get infestations
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  and control other crops that are particularly prone to whitefly include poinsettias
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  so they're they are a type of euphorbia from mexico and grown at christmas and also increasingly at.
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  Halloween the orange varieties and they are really
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  susceptible to whiteflies tomatoes anything
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  peppers really really susceptible and you
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  will find it on legal cannabis but it's not
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  the it's not the number one pest by any means it's not even in
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  the top five probably probably in the top
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  10 so those other crop it will it will affect
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  them and you can get infestations especially for outdoor crops growing
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  in very hot dry conditions where there's low air
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  circulation so be mindful of it look
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  for those small moth-like creatures and get
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  control as soon as you find them this will definitely be one that you'll find
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  will occur in your greenhouses especially in those those months where you've
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  got loads of whitefly coming in almost like an infestation that we said we had
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  a couple of years ago i suspect it's going to be even more of a problem with climate change meaning,
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  much hotter summers whiteflies will get hold earlier
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  on in the year and there might be infestations but the
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  key thing is look for them early always look
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  on the underside of your leaves when you're inspecting your crops not just for
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  whitefly but also for aphids next to the midrib is where they'll they'll be
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  hanging out it's also the same place where spider mites will be hanging out
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  they won't be hanging out just on the leaf the generic leaf area or on the margins
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  the edges of the leaves they'll always be going for the veins because that's
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  where the sap is so the sap suckers like.
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  Aphids and white flies that's where they'll hang out and spider
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  mites will hang out there because they're that's where the juicier tissue
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  is and also where they can hide away
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  from beneficials as well so always look on the
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  underside leaf next to the veins and use a hand lens if you
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  can and obviously just shaking your plants anyway will
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  release the white fly so if you're consistently getting white fly issues agitating
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  a few plants will will disturb them as
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  well so that's been hydroponics daily for today it's a pest it's not a happy
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  episode it's not a good thing but you know forewarned is forearmed is that the
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  phrase i don't know we'll do an exciting and interesting and happy episode tomorrow
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  and um but yeah you know the thing about gardening is.
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  Trying to not kill your plants and horticulture in
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  general not kill your plants and and then
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  eventually you get to enjoy them at the end well yeah that's
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  it our boriculture is a bit different isn't it tree growing
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  you get to enjoy your tree and then you get all the problems at the end
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  when enough to dispose of it but growing herbaceous plants
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  it's all about trying to overcome all these issues so you can get to
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  the good bits so hopefully you you aren't suffering from
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  white flies at the moment lots of people are growing outdoors at this
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  time of year so you might be suffering from white fly if you've
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  got any other pest or diseases that you want advice on
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  or if you need to diagnose a problem then just
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  send me some photos and i'm more than happy to have a look at them i'm not
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  a wouldn't describe myself as an expert when it came to plant pathology and
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  or entomology but you know i can give a stab and if not i can send it to one
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  of my friends who are world experts in entomology and plant pathology that's
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  been hydroponics daily for today thank you very much for listening to this drivel
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  and i'll see you again tomorrow goodbye.