So what actually kills aphids?


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I have an indoor veggie garden with LED grow lights. Chard, beets, broccoli, spinach, parsley, mustard, potatoes.
We all know spraying dish soap and essential oils doesn't do anything at all, and I'm sick of buying $30+ organic insecticides just to find out they don't really work either. There are many more products I haven't tried but they all have reviews that say it works and just as many reviews that say it doesn't work. So I have no idea which to try. I'm on disability so I don't have money to throw around.
I just finished up a bottle of pyrethrin concentrate. $30. I used it at 4x the recommend strength and drenched the plants in it every other day for several months. It barely keeps the aphids under control but never gets rid of them. If I skip 3 days they're back. And a lot of the plants died, probably from over-spraying.
So... WHAT KILLS APHIDS? I'm ready to consider something not organic at this point, because this is a serious waste of money and effort if I don't actually get any vegetables to eat.

Thank you.
 
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Aphids in Oregon must be different than the aphids in Texas. In Texas they are among the easiest insects to eliminate. I would like to see a picture of the Oregon aphids to see what the difference is.
 
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I'm far from an experienced gardener, but dish soap and neem works well for me. But that's outdoors.

Indoors you're creating an environment with no natural predators. One thing I've heard - and observed to be true in my garden - is that when a plant gets stressed they get attacked by aphids.

You can usually just rinse aphids off of plants. Also there are plants that are supposed to repel aphids - so garlic/chives etc. No idea how well this works.
 
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Aphids in Oregon must be different than the aphids in Texas. In Texas they are among the easiest insects to eliminate. I would like to see a picture of the Oregon aphids to see what the difference is.
PXL_20220911_213506916.jpg
 
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Very similar, but slight differences. These have longer antennae and have a more elongated body. But I don't think these differences make them immune from known aphid killers.

Question: When you spray does it kill all or most of them? And how long before they return?
 
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Very similar, but slight differences. These have longer antennae and have a more elongated body. But I don't think these differences make them immune from known aphid killers.

Question: When you spray does it kill all or most of them? And how long before they return?
Last year with just spraying dish soap they smothered and killed all the plants. This year with the pyrethrins (at 4x the recommend strength) they haven't been covering the plants but they're always there, hiding in the new growth in the middle. I had drenched everything in spray about 15 hours before I took this pic, and have sprayed the last 3 days.
 
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What soap and how much did you use per gallon of water? The soap is a contact killer which means you have to physically spray the insect. Residual soap really has no effect.

There was another thread with someone claiming the same thing about these indestructable aphids, here.
 
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My old shaving brush and a bar of the cheapest, softest soap seems to do it very well. It knocks them about and drowns them at the same time. I repeat shortly after to get those I missed, don't want survivors who may build some sort of tolerance.
Susan pointed out that it is stressed plants that get attacked, they spot a weakness and go for it, could it be that growing indoors creates unnatural conditions that make the plants more vulnerable?
 
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I will explain what I KNOW about aphids. Some aphids starts out as an egg. The egg is very very tiny and can be located on any area of the plant. Once laid the egg hatches, on average, in 5 days and the young starts reproducing in about 7 days. However, most aphids are born alive and the parent of the live born aphids are asexual meaning that a male is not needed in the reproductive process. These young start reproducing at about 5 days everyday for the rest of their life of about 30 days. One researcher did the math on how many direct descendants a single aphid had during its lifespan and it was 600 BILLION. Aphids reproduce faster than any other insect which is why it seems like you cannot kill them. An aphid is very easy to kill, probably the easiest of all insects but if you miss just one out of a hundred when you spray you will have about 400 within a week. And if the one you missed was a live born aphid even sooner than a week. You DO NOT NEED anything but dishsoap to control aphids although when severely infested you must kill the eggs as well as the insects and an oil is needed for this. Neem Oil is the best for the killing of eggs as it coats the egg and blocks all oxygen to the developing nymph. What you must do to control aphids is to make absolutely sure that ALL live aphids are in direct contact with the soapy water and that every leaf and stem surface of the plant is covered with the oil. If you miss one egg within a week you will have a lot of reproducing adults.

An aphid, when it is sucking on a plant is literally stuck to the plant by its mouth and cannot disengage from the plant. This is why a strong stream of water kills them. The force of the water washes the aphids away but the aphids "jaw" is still embedded in the plant tissue. So, when you spray your soap and kill them, the ones which were doing the actual sucking on the plant are still there. Dead, but still hanging onto the plant making one think that the soapy spray hasn't worked. They will drop off eventually but it is a bit disconcerting to see them looking like they were unaffected.
 
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'Dish soap' confused me rotten when I first came across it, we call it 'washing up liquid'
The stuff I use is a bar of actual soap (not detergent), I use it for shaving and keep it in a soap dish by the sink.
See why it confused me?
I have never truly experimented properly, but I have used 'washing up liquid' (AKA dish soap) when I didn't have the real thing, and I had the impression it really didn't work as well. I didn't get that thick lather, but maybe it is just that I enjoy that and the feeling the little b's are suffering :)
(and dying)

PS It works on blackfly on my broad beans as well.
 
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I will explain what I KNOW about aphids. Some aphids starts out as an egg. The egg is very very tiny and can be located on any area of the plant. Once laid the egg hatches, on average, in 5 days and the young starts reproducing in about 7 days. However, most aphids are born alive and the parent of the live born aphids are asexual meaning that a male is not needed in the reproductive process. These young start reproducing at about 5 days everyday for the rest of their life of about 30 days. One researcher did the math on how many direct descendants a single aphid had during its lifespan and it was 600 BILLION. Aphids reproduce faster than any other insect which is why it seems like you cannot kill them. An aphid is very easy to kill, probably the easiest of all insects but if you miss just one out of a hundred when you spray you will have about 400 within a week. And if the one you missed was a live born aphid even sooner than a week. You DO NOT NEED anything but dishsoap to control aphids although when severely infested you must kill the eggs as well as the insects and an oil is needed for this. Neem Oil is the best for the killing of eggs as it coats the egg and blocks all oxygen to the developing nymph. What you must do to control aphids is to make absolutely sure that ALL live aphids are in direct contact with the soapy water and that every leaf and stem surface of the plant is covered with the oil. If you miss one egg within a week you will have a lot of reproducing adults.

An aphid, when it is sucking on a plant is literally stuck to the plant by its mouth and cannot disengage from the plant. This is why a strong stream of water kills them. The force of the water washes the aphids away but the aphids "jaw" is still embedded in the plant tissue. So, when you spray your soap and kill them, the ones which were doing the actual sucking on the plant are still there. Dead, but still hanging onto the plant making one think that the soapy spray hasn't worked. They will drop off eventually but it is a bit disconcerting to see them looking like they were unaffected.
Dish soap + castile soap and neem oil did absolutely nothing. Spraying several times a day for 7+ days and it didn't even reduce the population.
Pyrethrins is keeping them under control, but I'm overusing it to maintain the effect. Spraying 4x the recommend strength, every day to every other day, and it hurts the plants.
 
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My old shaving brush and a bar of the cheapest, softest soap seems to do it very well. It knocks them about and drowns them at the same time. I repeat shortly after to get those I missed, don't want survivors who may build some sort of tolerance.
Susan pointed out that it is stressed plants that get attacked, they spot a weakness and go for it, could it be that growing indoors creates unnatural conditions that make the plants more vulnerable?
They're on the outside plants, too, but it's warmer inside. I keep a big box fan blowing at the area 24/7 but it still stays around 72° in there.
 
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There is something wrong with this entire scenario. Are you telling me that soaps and Neem did not kill them at all? That they are impervious to the chemicals? If so then I would have to say that by spraying generations of the aphids in an enclosed environment that they have built up an immunity to the chemicals and if this really be the case any research facility will pay you good money for access to your plants and your aphids in order to study and develop insect resistant pesticides. Pyrethrin is one of the most lethal organic pesticides in existence, even stronger than most synthetic insecticides and if that doesn't kill aphids there is something definitely off about this entire thing.
I don't know what to tell you except to start over. New containers, new soil, new seeds, new everything. And also this. Aphids are attracted to stressed plants and for some reason your plants became stressed which is why they showed up in the first place.
 
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I also wondered about using 4x the recommended strength. I don't know about this particular case, but often a strength is recommended because it is the most effective strength, making something four times stronger can have the reverse of the desired effect sometimes.
The bristles of my shaving brush do physical damage to the aphids, but are not strong enough to damage the plant.
 
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I also wondered about using 4x the recommended strength. I don't know about this particular case, but often a strength is recommended because it is the most effective strength, making something four times stronger can have the reverse of the desired effect sometimes.
The bristles of my shaving brush do physical damage to the aphids, but are not strong enough to damage the plant.
I'm using 4x because I started at 1x and it did nothing. You think I just jumped in and said f** these instructions, I'm making it stronger...? I tried it first as directed, absolutely 0 result.
 
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There is something wrong with this entire scenario. Are you telling me that soaps and Neem did not kill them at all? That they are impervious to the chemicals? If so then I would have to say that by spraying generations of the aphids in an enclosed environment that they have built up an immunity to the chemicals and if this really be the case any research facility will pay you good money for access to your plants and your aphids in order to study and develop insect resistant pesticides. Pyrethrin is one of the most lethal organic pesticides in existence, even stronger than most synthetic insecticides and if that doesn't kill aphids there is something definitely off about this entire thing.
I don't know what to tell you except to start over. New containers, new soil, new seeds, new everything. And also this. Aphids are attracted to stressed plants and for some reason your plants became stressed which is why they showed up in the first place.
Soap & neem did nothing from the first application, so it has nothing to do with building an immunity, unless they developed one before moving in here.
 
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I'm using 4x because I started at 1x and it did nothing. You think I just jumped in and said f** these instructions, I'm making it stronger...? I tried it first as directed, absolutely 0 result.
I didn't really think that, but there are those who would think 'I have tried other things, I'll try making it strong'. No way am I saying you are one, but you must admit there are plenty of people about who do have strange ideas, so just making sure.
 

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I'm surprised any of your plants are still alive with all that drenching.
I would go back and follow the instructions on the concentrate pack regarding strength and frequency of application. There are frequently other chemicals in the mix other than the active, for example wetting agents and solublisers. At too high a concentration the droplets may just run off before having an effect, or you may get uneven application.
The instructions are there for a reason and using higher strengths you are just wasting money.
Mechanical removal, finger and thumb works, wear gloves if squeamish.
 
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Mechanical removal, finger and thumb works, wear gloves if squeamish.
Or even a nice soft shaving brush that won't hurt the plant :)

There was a comment earlier about their jaws being locked onto the plant, so they stay there even when dead. Could it be that most are dying, but don't look dead and are then replaced by rapid reinfestation?
Could something else be supporting a small population locally?
 

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