Ladybugs as Aphid control?

Hello everyone,


I seem to be having a problem with aphids lately. I don't see the aphids, yet I see webs on my trees. I've been spraying with an insecticide for quite a while, with no effects. I've been reading online and read that ladybugs are natural aphid predators. Now, I'm curious. If you were to obtain ladybugs, would they only eat the aphids? Or do ladybugs also eat other insects/parts of plants? Just curious, not saying I'm going to be buying any ladybugs. Thanks for any comments.

They eat all kinds of other nasty pests as well. The problem is they never stay put. You release a hundred or so today and tomorrow there's only 10 or 20 if that.
I wouldn't put them on anything recently sprayed though. A hose works well on washing the little buggers off.

Thanks Robert. When you say recent, how recent are we talking? So they'll only eat the pests, not the actual parts of the tree?

I've also been reading up on Predator Mites, they seem pretty interesting as well...

I also read that they eat Scale, which would be awesome. Since I grow most of my trees in aquariums, I feel it would be easy to contain them in certain areas that I need them.

If your seeing webbing on your trees look to spider mites as the cause.

Every lady bug who overwinters among my tropicals indoors is a welcome friend but they only seem to eat the scale AFTER I squish them, the scale that is not the ladybugs.
-Jay

I personally never found lady bugs to be effective.The year I had a lady bug in my overwintering room I had to rescue it from my yellow sticky tape once and from my carnivorous pitcher plant once....lucky the pitcher plant didnt have any water in it.I also had problems with apids on a fuschia bonsai I have.I found persistance with neem oil effective....However you have to get the egg layers which hide on flourescent bulbs.

Yes ladybugs eat aphids, but unless you are overrun with aphids, they won't stick around to search for an aphid here and an aphid there. They go where the food is. They won't be happy outside this time of year, anyway.

But I doubt you have aphids. None I'm aware of create webs. Or, if you have aphids, they aren't the ones that are making the webs. Check out the top sticky in this forum -- the Rogues Gallery for what aphids look like.

Webs could indicate mites, but they also could indicate spiders -- which are better than lady bugs at getting rid of many pests. So do not spray indiscriminately.

Thanks Jim.

However, while repotting one of my trees today I did see an aphid, so I'm sure that is what I have. That as well as spider mites. And they are on some of my indoor trees.

I think I'll go ahead and try some ladybugs, just for fun. However, how long exactly should I wait to use them after spraying the trees with insecticidal soap?

Well, read the label to determine the contents of the spray, but if it is JUST the soap (sodium or potassium salts combined with fatty acids) you could set out the bugs after the stuff has dried. It is a contact insecticide, and has to be sprayed directly on the pest to do its job. There is NO residual.

Do NOT use if the soap concoction is mixed with rotenone or pyrethrins.

Thanks Jim! I read the label and it said Potassium Salts with Fatty Acids. So I went ahead and ordered some ladybugs, and I'll keep you all informed on what happens.

I received the ladybugs today and unleashed them upon the trees. They seem to be enjoying themselves and crawling all over the trees. However, something I've noticed is that they seem to be gathering around the base of some of the trees. Just something interesting I'm watching....

Looks like there is a feast there...you just cannot see.

Poink88 wrote:Looks like there is a feast there...you just cannot see.

That's what I'm hoping for!

MOISTURE. They have to get hydrated after their trip to you.

JimLewis wrote:MOISTURE. They have to get hydrated after their trip to you.

Oh yes, I know. I left them in a container with some soaked sponges for a while before I let them out.

Years ago I did a lot of experimenting with ladybugs and other natural predators in the commercial greenhouses I was operating. If you are having webbing that is probably (as someone before said) due to spider mites.

Adult ladybugs are really not that interested in eating aphids. They generally are interested in reproducing and laying eggs. They will search out infestations of aphids and lay eggs. In good conditions the eggs will hatch in a week or so. The resulting larva is the stage that eats lots of aphids - often hundreds in about a two week period. (The larva will sometimes eat spider mites, but they are much happier eating aphids.) Then the larva becomes a pupa which in about a week becomes an adult, and the whole process begins again.

The problem most have with this is they become too impatient. After the released adults fly away they dig out the pesticides. And usually the emerging ladybug larva are killed along with the aphids.

bill80132 wrote:Years ago I did a lot of experimenting with ladybugs and other natural predators in the commercial greenhouses I was operating. If you are having webbing that is probably (as someone before said) due to spider mites.

Adult ladybugs are really not that interested in eating aphids. They generally are interested in reproducing and laying eggs. They will search out infestations of aphids and lay eggs. In good conditions the eggs will hatch in a week or so. The resulting larva is the stage that eats lots of aphids - often hundreds in about a two week period. (The larva will sometimes eat spider mites, but they are much happier eating aphids.) Then the larva becomes a pupa which in about a week becomes an adult, and the whole process begins again.

The problem most have with this is they become too impatient. After the released adults fly away they dig out the pesticides. And usually the emerging ladybug larva are killed along with the aphids.

I was up at Meehans Miniatures this past weekend, and Martha told me the same thing. The larva are more interested in the bugs and will eat a large amount of them in a short amount of time. Oh well, guess I've got a ton of ladybugs for nothing then. I did go out and buy a horticultural oil however, as some of my trees have spider mites.

Spider mites are probably more difficult to get rid of than aphids. Spider mites have an egg stage that is usually impervious to insecticides. Then there is a larva stage and two nymph stages before the adult stage. When it is warm the time between an egg being laid to it becoming an adult that starts laying eggs can be as little as 5 or 6 days. Since you can't kill the egg stage, and there are probably eggs hatching every hour of every day, you may need to spray as often as every third day to break the life cycle. I once took over a greenhouse that was infested with mites. I sprayed every third day for one and a half months before I finally cleaned it up. (I used an ovicide - that didn't kill the mites but prevented them from laying eggs.)

Mites hate moisture, so spraying the plants with water not only knocks them off the plants but it discourages their reproduction and feeding. And you usually need to use water or some other means to destroy the webs. Webs will prevent the insecticide from reaching many of the mites.

So, you can get rid of the mites with just insecticidal soap but you need to be persistent. Good luck!

bill80132 wrote:Spider mites are probably more difficult to get rid of than aphids. Spider mites have an egg stage that is usually impervious to insecticides. Then there is a larva stage and two nymph stages before the adult stage. When it is warm the time between an egg being laid to it becoming an adult that starts laying eggs can be as little as 5 or 6 days. Since you can't kill the egg stage, and there are probably eggs hatching every hour of every day, you may need to spray as often as every third day to break the life cycle. I once took over a greenhouse that was infested with mites. I sprayed every third day for one and a half months before I finally cleaned it up. (I used an ovicide - that didn't kill the mites but prevented them from laying eggs.)

Mites hate moisture, so spraying the plants with water not only knocks them off the plants but it discourages their reproduction and feeding. And you usually need to use water or some other means to destroy the webs. Webs will prevent the insecticide from reaching many of the mites.

So, you can get rid of the mites with just insecticidal soap but you need to be persistent. Good luck!

Thanks again Bill. I was using an insecticidal soap before I bought this oil. Upon examination of a leaf under a microscope at the nursery, I was told the mites were still on the leaves, but most of them were dead. I was then given a horticultural oil and told it should kill the egg stage of the mites.

Ryan, I haven't had much experience using the horticultural oils. It would burn the foliage on many of the crops we grew. I would suggest you inspect the leaves with a magnifier three or four days after applying the oil. Then you will be able to see if you have a new hatch. Understanding the life cycle of the pest and being persistent can clean those mites up quickly!

bill80132 wrote:Ryan, I haven't had much experience using the horticultural oils. It would burn the foliage on many of the crops we grew. I would suggest you inspect the leaves with a magnifier three or four days after applying the oil. Then you will be able to see if you have a new hatch. Understanding the life cycle of the pest and being persistent can clean those mites up quickly!

Thanks Bill, will do. From what I was told it shouldn't harm the trees and is labeled to kill eggs as well as the adults. I'm curious though, what kind of magnification is needed to see mites on leaves? I think I may have seen some running up and down one of my benjaminas, but yet I couldn't see them on the leaves of my other trees....

Ryan,
I always carried an old Bausch and Lomb pocket loupe. It has three lenses, probably 3x to 9x or such. They aren't very expensive, probably just an inexpensive magnifier will do the job. Spider mites don't usually move very fast! Usually 3 to 6 times magnification will give you a good idea of what you have.

bill80132 wrote:
Ryan,
I always carried an old Bausch and Lomb pocket loupe. It has three lenses, probably 3x to 9x or such. They aren't very expensive, probably just an inexpensive magnifier will do the job. Spider mites don't usually move very fast! Usually 3 to 6 times magnification will give you a good idea of what you have.

Thanks Bill, I'll let you know what happens..

Ryan,

If you need a jewelers loupe, check eBay. You can get the 10x for as low as $0.99 free shipping or buy the 30x for $1.75 free shipping. I bought one and though it is far from being the best...I am very happy with it.