Aphid infestation on my Hoya! Help!

Carlsbad, CA(Zone 10b)

Help! Aphids invaded my Hoya last year (along with many other plants and trees in the garden) and are still here. Theyíre mostly on the flowers, which are numerous right now. I usually just spray aphids off with water, but with all the blooms I'm afraid I would spray them off, and because itís not trellised out it would be impossible to get to more than the front. (I no longer use systemic insecticide as recent bee research is showing that 30+% of bees have these insecticides in their systems.) Itís an 18-20 year old Hoya carnosa and since we moved nine years ago it has been given away and returned, had numerous moves, inconsistent water, too much sun, and no fertilizer. Amazingly it has survived and in two weeks will be moved to a better place where it will be happier and can be displayed appropriately.
I was hoping to have the aphids gone by then so as not to have to deal with the sticky residue and ants. One friend has suggested Neem Oil. Any advice will be appreciated.

This message was edited Jul 4, 2011 2:55 PM

Thumbnail by Anniesfollies
DeLand/Deleon Spring, FL(Zone 8b)

Hi Annie,
Wow...What a nice big Hoya carnosa you have there ! I can only say what I would do in your situation.
You know those bottles you can attach to a hose and fertilize your plants with ? I think I'd take one of those, put some dish soap in it, put it on one of the finer settings and try to reach as much of the plant as you can. Let it sit on there for a while and rinse off. I'd do this early in the morning too. There are insecticidal soap sprays you can buy also. You probably would have to repeat the application every few days or so.
I can understand you not wanting to use a systemic, we try to avoid using them also unless there is no other choice. In which case I usually remove the blooms from the plant for a while.

noonamah, Australia

The way Neem works is that it inhibits reproduction. But you still have the original adult population. That's why some people say that Neem doesn't work. The dish soap solution has a more immediate affect on all the pests. Repeat applications are usually required.

Chicago, IL(Zone 6a)

That's why Neem is often sold as "K+ Neem" or something similar. That preparation comes with horticultural soap included.

One of the "classics" is a tablespoon of liquid soap plus about a teaspoon of either high voltage liqour or rubbing alcohol per quart. Testing on a leaf or two is required, though. Some plants are more delicate than others and might suffer burn.

Either way: Put your plants into the shade before application and leave them there until the leaves are dry again to prevent burn marks and repeat every few days. Also, as soon as the Aphids are gone, give your plants a good shower with clear water to rinse off any remaining goo.

Well, and then there's always the "heavy artillery" like Malathion, Orthene.........


Carlsbad, CA(Zone 10b)

Thank you Mjsponies, Tropicbreeze, and Bsimpson1972 for your responses to my hoya question, and apologies for the delay in responding. The consensus seems to be a spray of liquid soap, and Neem Oil too, so that's what I'll do as soon as I can get both hands wet again and have my helper to move it into the shade. (Had to have some hand surgery that I thought would be more minor.) Also have several other plants that will get the same treatment. I do miss the days when I just put some systemic fertilizer/insecticide in many potted plants and they bloomed beautifully with no aphids, etc. It was so much easier, but I can't in good conscience use those anymore.
In case you're interested, TropicBreeze peaked my curiosity, so while I was sitting around I did some research (fingers still work) and found this article regarding Neem Oil, http://www.discoverneem.com/neem-oil-insecticide.html , which explains in detail how it works. I think it will become a regular part of my garden regime.
Thanks again to all!

Chicago, IL(Zone 6a)

I just have to throw in my 2 cents - again: Anything systemic like Marathon is great - for more difficult pests like root mealy bugs or Thrips. Just not for Aphids. Aphids are too easy to control without harsh chemicals.

DeLand/Deleon Spring, FL(Zone 8b)

Annie keep us posted...we all have gone thru the same situation. I hate to use chemicals unless it's absolutly nescessary. One thing you can do is to remove any blooms you have on the plant...that at least keeps any of the pollenators from using it and harming them.

San Diego, CA(Zone 10a)

just go to a garden center and buy a container of lady bugs. towards sunset, open the container and release the bugs at the base of the plant. The ladybugs will take care of aphids and whitefly also!

Carlsbad, CA(Zone 10b)

Yes stevelvv I should have bought lady bugs when the aphids first hit. Since I've been hampered by recovery from hand surgery all I've done is minimal spraying with water, but it must have worked as almost of the aphids are gone.

Now I'm debating about whether to give it away to a public garden. It's such a prolific bloomer, and a beautiful specimen when it's trellised out nicely, but I'm short on places where it will fit. I had a wall of the house picked out but my husband doesn't want it against the wood siding as he's afraid it will become invasive. In my experience Hoyas are such slow growers that keeping it under control would be easy, and since it's already so big I'm wondering if it will get much bigger. Does anyone out there have experience with this?

This message was edited Aug 13, 2011 7:16 PM

San Diego, CA(Zone 10a)

Here is a shot of aphids feeding on blooms that are developing. I spent $10 on a container of ladybugs hoping they would get in the nooks and crannies. I just can't keep up with the aphids using a q-tip and alcohol. They are getting bad. They ladybugs are definitely sticking around on the plant, but can't say they are eating the aphids like crazy, yet.

I have sprayed with Volck, and just a strong jet spray with water. Nothing really works. Any suggestions?

Thumbnail by stevelvv
in Houston, TX(Zone 9a)

I would put the whole plant in a the bath tub in soapy water and drown them. Let it sit in there for several minutes. Forgot to mention take it out of the dirt ,and get rid of the dirt . Repot with fresh soil later after soaking it in soapy water. I hope that helps.

This message was edited Sep 20, 2013 6:15 AM

San Diego, CA(Zone 10a)

Here are the results 2 days later. The aphids are gone! Just give them time and the ladybugs will eventually feed on the aphids. There are quite a few ladybugs still on the vines (3 plants in different pots) so hopefully will just let them take over and do the work.
Here is one bloom opened and 4 more opening soon.

Thumbnail by stevelvv Thumbnail by stevelvv
Carlsbad, CA(Zone 10b)

After I posted in 2011 I ended up just spraying my plant, (picture above) and all the others that were infested with water, and picking off a few really infested leaves. Kept meaning to make a batch of the soap/alcohol spray but didn't get too it. 2011 was a really bad year for aphids in my yard but I will not use systemics. If I have an infestation that bad again I will try the spray and then purchase ladybugs and . 2012 and this year have been much better, and although the Hoya again had aphids it's such a large plant that if I can keep it partially under control the plants still does fine. It has bloomed beautifully every year, even with inconsistent water and a bit too much sun.
Stevelvv that is a beautiful flower, much darker than my basic Hoya carnosa. Do you know which one it is?

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