Worms on my Hibiscus!

Villa Rica, GA(Zone 7a)

Every year I get these little green worms on my Hibiscus! They eat the leaves and make them look awful before it can even make buds and bloom. Is it something about Hibiscus? I mean I have 3 or 4 and they are all in different places in the yard and the worms have found every one of them!! They don't seem to eat the other plants around the hibiscus eaither. I got out there today and started pulling off the ones that were holey then started checking the other leaves for any sign of the greeny meanie's and sure enough I found some that were sooooooo tiny!! I mean all you could see was the tiny heads and tails, the middle parts of them were clear! They look like tiny strings.
How do I get rid of them so that my hibiscus wont look so pittyful come bloom time??

hibiscus are prone to aphids and other garden bugs. If hibiscus leaves become yellow with green veins, that may indicate the plant has an iron deficiency, which means it needs food. And to keep them healthy, treat them with a fungicide at least once a year.
Using water-soluble fertilizer will help keep the plant healthy throughout its growing season, which lasts until late summer.
The more you use fertilizer blended specifically for a certain plant, the better the fertilizer works.
With the right care and the right weather, the tropical-looking blossoms may hang around for a lot longer through the summer.
Having good healthy plants; you are more apt to have less trouble with the plant.

Villa Rica, GA(Zone 7a)

I don't seem to have a problem with the getting yellow leaves, just gets green worms on them. Far as I can tell the plant is and was very green and healthy before the worms came along and started munching on the leaves.
I just want to get rid of the worms, any idea on how to do that? Aside from hand picking them off which I have already done.
Wonder if there is something I can mix up here at home to spray on them??

Jonesboro, GA(Zone 7b)

Molly, I have the same problem and they look awful. Sevin will work, but with all this rain, it seems an endless chore. Maybe an oil spray like Neem oil or Volk oil would stay on better. I completely lost the only pale pink one I had last year because of those little green buggers. Hope someone comes up with a better cure.

PS: Hope you are planning to come to the swap on the 31st!!!

This message was edited Tuesday, May 20th 7:47 AM

"Leaf eating worms can be controlled using products containing Bacillus thuringiensis such as Dipel, Biological Worm Control and Thuricide. Most insecticides are not phytotoxic to hibiscus"
quote taken above from following article.


Villa Rica, GA(Zone 7a)

At this point I am willing to try just about anything. I'll check out Wal-Mart and see if they have anything that will control these baddies!
(Hoping to come to the plantswap PJ, I'm sure it will be so much fun!)

Thanks CoCo heading to look at the link now.

Marietta, GA(Zone 7b)

I am bumping this thread since I have those little buggers and they have just about chewed through my two disco belle hibiscus and I DID spray with Seven after the garlic and insecticidal saop treatment made them laugh at me. Now they are on to different plants... hibiscus of course. Nothing else other than the confederate rose...which is also a hibiscus come to think of it, gets attacked like this.

I really like my butterflys and don't want to spray seven unless necessary, but what else can I do?? What are they??


The Woodlands, TX(Zone 9a)

Sounds like the "cotton square borer" which is the larval stage of the gray hairstreak (a butterfly).
Google cotton square borer and you will see images of the adult stage and the caterpillar stage. Is that it? If so, the least toxic control is Bt. It only affects caterpillars - the younger, the better.

Deep South Coastal, TX(Zone 10a)

If you like butterflies and have caterpillars that you don't want to kill, be very careful using Bt. It kills all caterpillars including swallowtail and monarch cats.

Marietta, GA(Zone 7b)

ceejay, nope thats not it... Hi Cala, My camera should be back from the shop any day now.. it is small, like the length of my fingernail and almost transparent. I had already looked at some leaves and then on closer reexamination discovered how they almost got away from detection. I spent a bit of time hosing them off another hibiscus yesterday and I will be keeping a very close eye on them. I love our butterflys and have planted lots of plants that attract them... However, I am unwilling to have shredded hibiscus.. if I can't find an acceptable way to prevent this, I will do away with them all. What about Bayer 3 in 1 systemic?

I have not used Bt, but I have used Seven and I'm guessing it kills everything..butterflys included. I'm not sure if I cross contaminated the measuring cup I was using with a prior application of round up, but I previosuly sprayed seven on some phlox that was being chewed and I lost a few and some others still look very ratty & yucky.. Does seven harm plants as well, or did I jsut mess up?



The Woodlands, TX(Zone 9a)

Sevin kills all - butterflies and the good guys included. Bt kills only caterpillars, but as Calalily says, that includes the butterfly caterpillars. If I had to choose one, I would go with the Bt and keep it away from all other plants. Sevin liquid should not hurt any plants that are listed on the label. I remember there was something that it was injurious to, can't remember what, but that would be listed on the label also. Sevin dust can cause phytotoxicity and is not recommended because bees can get into it and carry it back to their hives. Not a pretty picture.

Other possibilities:
(Anomis erosa): Also known as the okra caterpillar. Caterpillars are light green and grow up to 1 3/8 inches in length; they are similar to the cabbage looper in appearance and walk in a manner similar to loopers.. They feed on leaves of okra and related mallow family plants in the southeastern US. They are yellowish green or green and have a dark stripe down the back. I could only find pictures of the adult under the latin name.

Another could be the corn earworm, also known as the tomato fruitworm or cotton bollworm - because they have a wide range of hosts, including hibiscus. Now, that one you can google and find pictures.

Both of these are green.

Whatever you have, Bt will work, because they are caterpillars.

Good luck! I'm sure glad I've never had that problem on my hibscus. Only aphids - and the beneficials take care of them.


Edited: Oh, yes, once you have used Roundup in anything - sprayer, cup, measuring spoon, etc - never use it for anything else. Write on that item with a permanent marker: Roundup. Cross-contamination is a big problem with Roundup.

This message was edited May 23, 2006 5:36 PM

Marietta, GA(Zone 7b)

CJ, thanks so much for the feedback :) I have googled both and like you could not find the first one and it is not the second... I will post a picture just as soon as I can.. Hopefully they will have been irradicated first.

I am convinced they have "memory". Last year, the first year my disco bells were in the ground, they grew huge and the blooms were absolute show stoppers and cars would slow to see them. After bloom, they started getting shredded and I wasn't on top of things (two young boys) and by the time I got around to them, they were so bad I just cut them back to the ground and hoped for the best. They started to return during the same season, and they have obviously returned this season, but now it is a few months BEFORE bloom and they are already under attack. I have recently planted other hybiscus in the front yard and while I have found some of the same varmits on some of my new plantings, it is nowhere near the same damage and infestation as the ones that were planted in the ground from last year... They have it in their genetic code to eat my disco bells!! I can't stand to see the damged leaves and don't know if I should cut them back now and if I do if I will still get any blooms this summer... last year there were tons... this is sad!!

Isn't their something (Bayer 3 in 1) that can be placed down as a fertilizer that is systemic and kills the insect that eats the foilage? I would need to make sure my hibiscus is covered as soon as it broke dormancy.

I can't wait to get my camera back and will post evidence ASAP!


Marietta, GA(Zone 7b)

I found it! Hibiscus Sawfly Larvae...

The PDF link I just posted doesn't work, so a google search may..


This message was edited May 23, 2006 8:21 PM

Marietta, GA(Zone 7b)

A perfect picture...


Austell, GA(Zone 7a)


Do try the systemic - that does seem to help. So far mine have not been attacked this year.


Marietta, GA(Zone 7b)

Thanks Brenda... I am going to do the systemic around all my hibiscus. I was venting to my husband about the Hibiscus sawfly when it occured to me that they don't have memory, but maybe the eggs are laid at the base of the plant and they sit overwinter waiting for their food to break dormancy? How's this theory?? Any experts out there?


The Woodlands, TX(Zone 9a)

Is the systemic you are talking about the one that has imidacloprid as the insecticide? If so, I would say go ahead. It is toxic to insects, but has a low toxicity to mammalians. I believe you just water that in around the base of the plant. If the one you are talking about has disulfoton as its insecticide, I would urge you not to use it. Disulfoton has a very low LD50, which means that it is highly toxic - and it is highly toxic to mammalians. Dogs, cats, children, critters...

I'm glad you were able to ID your critter. Again, good luck.

Deep South Coastal, TX(Zone 10a)

How about sprinkling them with diatomaceous earth or spraying them with pyrethrins?

Marietta, GA(Zone 7b)

CJ, Gee I haven't the foggiest notion... I need to go look at it tomorrow and get back to you. I have 2 small boys, a dog, cat and I really am inclined to not do any harm to my family or myself for that matter. I can name many times when I've accidentally cross contaminated with Round up no matter how careful I thought I was being... Like the time I finished spraying, took my shoes off if in the garage then took my clothes off in the laundry room and then showered. Went back, put my clothes in the wash and went to eat and apple and ate roundup residue in the first bite... How'd that happen?.. The spray had squirt on my clothes and I had obviosuly touched it with my hands to go in the laundry before I sliced my apple. Gross and phewy!!

However, I am not at all able to currently sustain an organic garden (I tried for some time and the dermatologist doctor in a high traffic Atlanta practice said it was the worse case of poison ivy he's ever seen and I got two shots instead of one.) The neighbors of origin are still on my "list". And since I just recently acquired a slew of roses, it doesn't look as if I'm going to be able to go completely organic anyway... I still am concerned for the wellbeing of my family and the beneficials.

Cala...going to go look those up and I'll get back as soon as I know what they are! :) I've heard of them...just not enough to be familiar..


Deep South Coastal, TX(Zone 10a)

Diatomaceous earth for agricultural use, almost the same thing used in swimming pool filters and diatom aquarium filters(the stuff used in filters has been treated and doesn't work as well). It isn't poison, the sharp edges cut their little exoskeletons to pieces and they dehydrate and die.
Pyrethrins, be sure they're "natural pyrethrins" because there are lots of synthetic ones on the market. They are derived from a type of chrysanthemum flower, break down in 20 minutes or less to harmless ingredients. Pyrethrins damage the nervous system of insects and they die, harmless to humans.

For roses: neem oil is a wonderful rose spray, keeps aphids, thrips and mites at bay and also is a great fungicide. Another natural spray for roses to keep black spot away: chop up 1 cup of tomato leaves in a blender and steep in a quart of water overnight, strain and spray your roses. Tomatoes contain something that kills black spot on roses.

The Woodlands, TX(Zone 9a)

I wouldn't say that Pyrethrins are harmless to humans. Its benefit is that it breaks down quickly in the environment, but it is just as poisonous as many other insecticides - just not as persistent. It kills beneficials too. If the "worms" are on the leaves, I don't see how you can treat with DE. And be careful not to breathe it. See - there are many caveats in "organic" gardening, also. I prefer going the IPM method. Least toxic and only on the affected plant, and only when necessary. Least toxic here is BT. But she apparently doesn't want to spray. So next in line would be a systemic that doesn't affect the beneficials or other critters: Imidacloprid, watered into the base of the plant fits that description.

This message was edited May 24, 2006 7:17 PM

Marietta, GA(Zone 7b)

Cala and CJ, I am most greatful!

DUH!! I remember DE now! My husband sells the stuff! For goodness sakes... I knew it was very familiar.. He is in the pool industry and I have spoken with him about using it around my hosta. He said that it may not be the same as the horticultural application product, and he also felt that it would wash away. I never did try it, but I just use crushed egg shells and at times collect sweet gum balls and spead them all around the hostas.. which reminds me that I should be doing that soon.

Thanks for the tips for my roses! I will use neem, which I should have already been using and tomato sucker leaves for the spray.

I would appreciate a name brand of your favored pyrethrins and Imidacloprid and where to look for it! I am not at all opposed to spraying, I just want to do the least amount of collateral damge and have great looking plants. Also, I do not have any experience with all the different products available for such applications, which is why i am so appreciative for your help. I did just spray with seven... I had to do the remaining hibiscus that I had sprayed the leaf undersides with water, as I discovered the littlest tiny worms emerging and I realized that there was going to be a continuing cycle of them hatching unless I sprayed them with seven, which I did. Also, I own a slew of cannas and from experience last year, there is no way they can get through the season without getting shredded unless they are sprayed and protected from those canna leaf rollers. Thanks!


Monroe, NC(Zone 7b)

I agree with CeeJay! Pyrethrins are not harmless to humans and other living creatures, even if some are organic. It is a nerve toxin any way you look at it. I'd go for the BT if you are trying to kill caterpillars. I don't think that hibiscus is a major food source for most butterfly caterpillars anyway. Also BT's are about the least toxic to all the other creatures. The imidacloprid. It is a soil drench and is taken up by the plant systemically so it only affects the bugs that actually are eating the plant. Doesn't do too much collateral damage. Oh yea, it doesn't kill caterpillars very well! It is better on aphids, white flies, mealy bugs, etc. Isn't imidacloprid the active ingredient in Bayer tree and shrub insect control in the blue bottle? If you go that route, careful handling it. It also has some toxicity.

Marietta, GA(Zone 7b)


Union City, CA(Zone 9b)

Swinming pool DE is not the same as ag DE .
Ag DE is heat treated to make it explode - with makes litte saws .
Swiming pool DE is just little bones from sea creatures


Monroe, NC(Zone 7b)

Hi Susan: A promised, I asked our entomologist, Dr. Ned French about your bug. Here is his response. Of all the products he suggests, I would go with the spinosad. I think it is the safest. Looks like the BT is a no go because the pest is not really a true caterpillar so it wouldn't work.

Hi Robin - Hope all is going great for you. Here’s a link with some good info:


I know Blake, and he’s a good entomologist.

The choice of product depends on whether this is a homeowner or commercial situation. Either way, because this critter is a defoliator, I don’t think that they’ll have any trouble controlling them. Products with A.I. such as permethrin (or other labeled pyrethroid), spinosad, and acephate (really good for aphis and such) are options that quickly come to mind. Just remember to get good coverage and to include Messenger in the sprayer. I suspect that larvae will reappear later in the season, as Blake noted, so be prepared to treat for them one or two more times.


Marietta, GA(Zone 7b)

Great thanks!! :)


Now to find that product??!!

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