Hardy hibiscus in Georgia

Thank you for the post. I have identified the insect as Althaeus hibisci which is a bruchid seed beetle which specializes in Hibiscus, thus its name. Is the number one killer of hardy Hibiscus seeds in North America These beetles developed inside the seed as larvae and emerge as adults. Until the beetle emerges the seed looks normal. In a related paper I learned that the nonviable seeds sink while viable seed float. Your overnight water bath may be an excellent way to separate the good and bad seeds and not waste time planting the bad seeds. What I could do is separate the floaters and the sinkers and try germinating both using your method which allows visual inspection of the germination rates. I am going to try your technique with and without seed nicking as I want see if the good seeds float.

All of my findings are posted here:
http://davesgarden.com/community/forums/t/1055744/

I did expose a batch of seeds to Ortho's "Home Defense Max" from which the beetles were actively emerging. Within five minutes there was no more beetle activity. I just hope that I did not kill the good seeds. After 12 hours I am reasonable sure that the unmerged beetles were killed inside the seeds. I will have to try Malathion next.

Now here is BIG question. Next summer how do I kill the adults before they lay their eggs on my Hibiscus flowers?

Again, thank you.

Mike

Hmmm....! That particular named bug was not listed in my bug book, but the lifecycle is the same.

Don't count on the viability of seeds that float or sink. Floaters may be resting on a tiny air bubble. I have found many of those will germinate just as well. Actually, sometimes if you just touch a floater it will sink.

As far as your big question, my book recommends treat seeds with lindane before planting. I'm sure there are other bug killer available. The problem is that more are probably waiting outside ready to attack again next season. The only advise I can give you on that is to keep a sprayer full of Malathion handy and be on guard. Squirt a few drops of liquid dish soap (Joy, etc.) to act as a sticker. Otherwise the spray will just bead off the plant/s. I have trouble with aphids on my roses early in the season. I keep Malathion handy for that. It doesn't loose its effectiveness when mixed with water and stored in a container, such as a sprayer.

How often to spray depends on the insect's habit. At least once per week. See if you can find out when they are the most active, and when that starts in the season. Malathion kills on contact, as well as ingesting sprayed parts. Maybe you can get information from your local extension service.

Good luck. Let us know the results of the seeds.

I wonder how well the Bayer Tree and Shrub drench would do for these bugs? I have not used it myself but know outstanding gardeners who would not be without it. It is a systemic that you pour it around the plant only once a year. That has to be easier than repeated sprayings that may or may not get the critters.

Blomma,

I have two additional questions.

1. For nicked and un-nicked Hibiscus seeds what are the typical germination times or when should I start checking for roots?
2. I am having difficulty visualizing the placement of the seeds on the paper towel relative to your folding instructions; could you be more explicit? If I follow your folding instructions I have a rectangle not a square.

By blowing up the ZipLock bag by mouth you also increase the level of carbon-dioxide in the bag but I am not sure that this would be of any advantage to a seedling which was not actively photosynthesizing or if there is any benefit to seed germination associated with elevated levels of carbon-dioxide.

Thank you,
Mike

My seeds have been in two different bags and started to sprout the end of the second week. I think I had the paper towel to thick. I got an early Christmas from my DH. A seedling heating pad. I was talking to myself and he must have over heard me. 35 years ago when we were first married I would hint out load many many times and he never got it. Know at our age it is very difficult to find either one of us a gift because there is nothing either on of need except stronger backs and knees. The reason I had two bags was an experiment. I soaked some seeds in peroxide and some in hand hot water. The seeds soaked in water started to sprout first. We have Direct TV and the box is barely warm. So it will be interesting using the heating pad.

Blomma, my only question is hand hot water. Is it only suppose to be hot at first or do you keep replacing the water? I did not replace the water. And thank you so much for your expertise...

should never have posted those links, saw some hibs on sale!

Mike I never sowed hibiscus seeds without first nicking them so no answer to give you on that. As far as nicked seeds, I soaked them in handhot water overnight, allowing the water to cool naturally. Planted them in the paper towel the following evening. It took 2 days to sprout, see photo in my post above. I don't know if this short germination time is normal, or it depends upon the variety of hibiscus. You do need to nick to allow moisture into the seed for it to swell.

Sorry, I forgot to mention to cut the paper towel in 1/2 first. Then fold it in half twice and you should have a square. It doesn't have to be square as long as the seeds lay between 4 layers of paper towel to prevent from drying out and to cushion them. Open the last fold and place the seeds on the side of the fold. Now refold the napkin over the seeds.

The only reason I say to blow into the bag is so that the plastic isn't laying on the paper towel inside the bag and mat it down. The bag serves as an ultra mini greenhouse. I have no idea if the carbon dioxide does any good. But sure can't hurt.

I would check your seeds every day, starting on the 2nd day. They can sprout overnight.

I did some open pollinated daylily seeds the same way to test them. They sprouted in 2 weeks in cool temp on my window sill. They are now 1-1/2" tall, potted. Although an experiment, I couldn't toss them and spring is soooooo far away.

skwinter Yes, the water for soaking is hand hot first, then allowed to cool naturally overnight.

Glad you got the heating pad. That should work. Keep us posted on how your experiments turns out.

Photo is of the daylily seeds Oct 21 just before planting up. The 4th one would have sprouted also since it is swelled but 3 was enough.

What i did and seems to work I soak them over night in water then i nick where it looks like its going to start to grow (the pointy part) then i plant them in dirt and stick them in my fish tank.. In only a few days they are gowing.. I soaked them nov 10 - nov 11 then planted them the afternoon of nov 11 this is what i have already NOV 14!! this first one is lady baltimore..


This message was edited Nov 14, 2009 7:49 PM

Blomma,

OK, four-ply it is, I agree that shape and size are really quite irrelevant but paper thickness is not. Actually that gives me greater flexibility as I stated two bags with over a hundred seeds each last night.

After some though I decided to not nick the wild Hibiscus moscheutos seeds because these seeds are significantly smaller than the seeds we collect from our named domestic cultivars or other wild species such as Hibiscus coccineus. When I first saw the seeds of wild H. moscheutos I thought that there was something wrong until I check the USDA database and verified that wild H. moscheutos seeds are significantly smaller than other Hibiscus. What is being sold in our garden centers is not H. moscheutos but hybrids of multiple Hibiscus species including H. coccineus and seventy-five plus years of selective breeding. Let’s be honest, do breeders select small seeds or large seeds to breed the next generation? Bigger is always better or is it? In any case, I was working with over 200 seeds in this test and nicking that many seeds of this size would have been no small task.

All of these seeds were treated with Ortho's "Home Defense Max" based on the recommendation in other posts; and, yes I have now purchased Malathion for the next round of tests. When I put the 200 plus seeds into hand-hot water and the seeds which I suspected were compromised swelled to twice their normal size and began to sink. What appeared to be healthy H. moscheutos continued to float. The shells of the sinkers were soft and when I cut a few of them open I found what appears to be a very dead Althaeus hibisci inside each compromised seed. Having recently switched from DiectTV to Verizon FiOS I used the FiOS interface unit to keep the water bath slightly warm for a full 24 hours. Using a fish net I separated the floaters and the sinkers into two groups of about 100 seeds each and setup two of your four-ply germination ZipLock bags. The two bags are now on a disposable aluminum baking tray on top of my FiOS interface unit and are slightly warm to the touch.

The sinker seeds were very distressed and I suspect that if I attempted to nick them they would have been destroyed in the process. I don’t expect many of them to germinate. The big question is: are the floaters still viable after the Ortho treatment? I have growing seedlings from this batch of H. moscheutos so I know that some of the seeds were good before the Ortho treatment.

I have reached out to www.BugGuide.net and offered to send them a batch of my infected Hibiscus seeds, live bugs and all. They have pictures of several suspected Althaeus hibisci sightings but they are not listing them as confirmed identifications at this time. I will even try to collect additional H. moscheutos pods if they are still available with seeds. It is important to the Hibiscus hobbyist’s community that we have verified pictures of this beetle on the Internet. I never want anyone to have to go through this again unawares. We desperately need a treatment protocol to kill Althaeus hibisci in the seeds while not killing the healthy seeds, otherwise anyone in a high risk area should not export Hibiscus seeds in trade. On Bug Guide you can also post eradication techniques or any general information about the bugs on the species page.

Normally I do nick Hibiscus seeds and have several batches of large seeds from outside of New Jersey which I will be germinating is a few day. Using normal indoor germination techniques I have very limited success with seeds which are not nicked. Hopefully Santa will bring me one of these seedling heating pads soon. Perhaps if I keep germinating seeds in the TV room I will get my wish!

I will be running Malathion tests and was wondering if you have any ideas for concentrations which should be used to soak Hibiscus seeds? I will check the Internet to see if anyone else if bathing seeds in Malathion. After doing some reading there are many safety advantages in using Malathion and I now wish I had tried that first.

I will continue to update this Hibiscus Forum post:

Help: Insects Eating My Hardy Hibiscus Seeds
http://davesgarden.com/community/forums/t/1055744/

Again many thanks,

Mike

Wow Mike, you are really into this! My hat is off to you. If you solve the problem through your testing, I'm sure many will thank you. You are right that if should be tested and reported for others to learn from. I didn't realize that these bugs were so prevailant with Hibiscus. Also, I didn't realize, or gave it a thought about native species of Hibiscus having smaller seeds. And yes, to nick 200 seeds would be quite a task.

As far as the concentration of Malathion for seeds, I would follow the directions. If made too weak, it may not kill the bugs. What I would do for those seeds that you can nick, I would put them in hand hot water to soften the seed coat, then finish off with a few hours of Malathion bath just before putting it the paper napkin. You can even use Malathion to dampen the napkin with, instead of water. Now that is a thought. The bugs--if any-- would die on their way out and literally walk to their own death.

Looking through all my containers of bug poison, I saw that Sevin will kill potato weevils. Maybe it will kill your Althaeus hibisci too. Comes in both liquid and powder. I use the powder and sprinkle it around my Sempervivums where sowbugs love to hang out after a rain. You should see all the dead bugs in the morning.

In anwer to your question, I don't see why the seeds wouldn't be viable after the Ortho treatment.

Yes, using the TV room may get you your seeding mat. However, you really don't need it since many spots are warm enough. Even 70 degrees is fine. (whispered tone). But I won't tell.

If all germinates, what will you do with all the seedlings?

Yes, please keep us posted. I am very interested to know the outcome of your testing. Hope it work so you can get it on Bug Files. Good luck.

Lilly

Hey, the light just went on. I think my hardy hibiscus is a native hardy because the seeds are very small. I had it over 15 years. I brought a portion of it with me when we built our new home 8 years ago.

to nick the seeds i use nail clippers its really fast and works on all types of seeds including cannas which are rather hard to nick.. NO i agree Mike i wouldn't do 200 of them either but for just a few it works..
jen

I use the following Exacto Knife with a five-pack of replacement blades, so that I always have a sharp blade to work. If you don’t have a very sharp blade you increase the possibility of damage to the seed.

http://www.gerrymay.com/wp-content/uploads/2009/07/exacto.jpg

I work on a large white paper plate to improve visibility and avoid damage to the work surface. On the side opposite to where the umbilical connected the seed to the pod make an outward and downward cut to remove a saucer shaped section of the Hibiscus shell. Attached is a photograph of how the seeds should look after the nicking.

Nail clippers are much too dull and would apply too much pressure on the Hibiscus seed but they might be OK for large seeds.

Mike

Mike I would love to do that but my luck with a sharp knift i for sure would cut myself as those seeds are so tiny... Love the idea of the white plate never thought of that..

I too use the corner of a nailcutter. I don't nick at either ends since seeds seems to emerger from those side. I nick in the middle of the seed.

JudyinGA Here is a website for both hardy and tropical Hibiscus. $15.00 each. Not bad for a particular variety. You can also find the famous Fleming brothers Hibiscus there.

http://www.plantdelights.com/Catalog/Current/page42.html