Wilt disease!

[luthienj]

Ahh, I have the dreaded wilt disease in my only surviving seedling from a sun showers x living legend cross!

I've repotted the plant in fresh clean soil and am only watering as needed. I've also treated the plant with SuperThrive growth hormones and it seems to be doing ok. There is some new growth.

However, I'm still concerned, because there are small pin-sized black spots on the leaves. They started on the lower leaves and are spreading upwards. I'm concerned that this is the fungus spreading upward thru the circulatory system. Are there any fungicides that can be applied to treat systemic fungus? Please let me know!

[Charlie]

New growth is an excellent sign it is recovering. I take it that there is no more wilt of the leaves?  If this is so then it has a good chance to become as good as new. Try not to overwater it during the rest of the winter (but it needs some, too). Black spots in winter are fairly typical for hibiscus and not a sign of wilt disease. You can treat the hibiscus with Bayers 3-in-1 which contains a fungicide. Some of the copper or sulfur based ones from Safer Company will also help with leaf fungus. Hibiscus rarely have a serious problem with leaf fungus if the leaves are able to dry out during a typical day. Summer usually takes care of any problems, with winter spotted leaves falling off to be replaced by new foliage quickly in  spring or early summer.

Good luck and be sure to let us know if there is a change that concerns you!

Charlie

[Charlie]

Question sent to HVH by P.M.

Hello, I have one of your Hibiscus that I purchased a few years ago that I love dearly. I have had it look like it was goinf to croak on me a few times before and I have always been able to bring it back to health with you very helpful website and newsletters. However, this past Thursday I noticed that all of the leaves were wilting and the soil looked a little dry so I gave it some of your fertilizer and water in hopes that it would look better in a day or two...I was wrong. My plant looks awful! The leaves are more wilted and they are turning yellow! I read your info on Wilt Disease and it sounds like the right diagnosis and I am willing to try some of your suggestions but I am so afraid to add anymore water to the soil...should I try the bleach mixture first or take it out of the pot? I am just sick over this! I am so afraid that I am goind to lose my precious Hibiscus that I have nurtured to a large beautiful mature plant. Please get back to me at your earliest convenience...I would really appreciate your help!

[Charlie]

Sorry to hear about the ailing hibiscus. Wilt disease may or may not be the right diagnosis in this case. What makes it questionable is that wilt disease is rarely if ever associated with a dry pot. The organisms that cause it are called water molds because they live, move, and multiply in water. Potting mix that is on the dry side is not conducive to them causing wilt disease. However, dry potting mix plus cold could cause the leaves to wilt also, without any disease present. The question is whether this plant is outside and whether you had a night temperature that dropped close to freezing the night before you saw the problem. Hibiscus react to cold by wilting and it is worse if the plant is on the dry side. If the temperature actually went below freezing that would explain how bad it looks now. If that is the case the leaves will all fall off but there is a good chance the plant will survive and put on new leaves in the spring.

If you are pretty sure that the plant did not experience cold then we are back to wilt disease. Your best chance to save it if that is the case is to take the plant out of the pot and wash all the old soil off the roots. You will lose some roots too when doing this but that does not matter. Hibiscus benefit from root pruning from time to time just as they benefit from pruning on top. Once the old soil is washed off then repot the plant in fresh potting mix that is lightly moist before you repot (not wet). Then you can only wait to see what happens. Give it just enough water so that it never dries out totally, but do not overwater. Wilt disease is often fatal, but the best results I have heard about came from repotting in fresh soil. If for some reason that is not feasible then the next best thing is to soak the root system one time only with a 15 to 20 percent bleach solution and then wait to see what happens.

One last suggestion. If the hibiscus seems to stabilize and neither dies nor gets much better you might want to try applying HVH Growth Enhancer. This product contains naturally occurring growth hormones that help a lot with any type of plant stress.

Good luck!

Charlie

[Pachrian]

Charlie, is wilt disease contagious? I'm asking because my Saffron just suddenly died on me and it was in the same pot that Cinnmon Girl, which died at the beginning of the year from what I assume was wilt disease, was in.

[Charlie]

Whoops - good chance that the pot spread the disease. Pots should only be re-used after cleaning and sterilizing with bleach/water, and that goes triple for pots in which plants died from disease. Disease is spread by insects going from one plant to the next, by pruners used on multiple plants, and by water splashing from one pot to the next. It can be spread by hands though this is less likely. Re-using potting mix is also a bad idea for this same reason.

Fall is a sensitive time for hibiscus, as they adjust from the temperatures tropicals are supposed to have to colder temperatures. For that reason its best to have finished all potting up or other changes such as pruning well before cold weather starts in fall.

Sorry about the Saffron.

Charlie

[helixturnhelix]

I am pretty worried about wilt disease too, especially moving to a humid and cool environment.  One branch on my Vin Ex, had it, but I cut it off and I think i got any rot before it spread.  You have to be very diligent about not spreading disease, I wipe my scissors off with isopropanol after every cut when pruning.  I am especially worried because I had to prune everyone before moving and when I got to my new place it rained for 5 days strait.  So far everything looks ok, but I am going to invest in a small clip fan to keep the air moving in the growing area to prevent and bacterial or fungal disease.  Hopefully with the high humidity here, and relatively cool weather spider mites will not be a problem like they were last winter.  Spider mite casualties to date include: Living Legend, Rosalind, Wild Dream, and Black Cherry,  Wild Dream and BC were a huge loss.  Hopefully there will be some BC or look-a-likes in the pipeline... Sigh good luck overwintering!

[Pachrian]

Oh dang, I've got to learn to listen to my gut. Had a feeling it might be a bad idea to re-use the pot but I needed one NOW. Lesson learned...I hope

[Charlie]

Uhh, I feel your pain, Chris. Those are some good ones to lose. How does it happen? Spider mites show up, whole plant defoliates, and then what happens? Slow decline or rot sets in? I find that if the mites are caught before total defoliation then the plants usually grow back using the few remaining leaves to provide the energy to get started again. We need a better miticide for home use, seems like.

Charlie

[Charlie]

Been there, done that, too, Uli. Sometimes there are no problems but with valuable plants it's best not to take the chance.

Charlie

[helixturnhelix]

Sigh, yup they defoliated and never could quite make it.  They had new sprouts, but they stopped doing anything and after about two weeks turned brown.  Alas the plant was gone The biggest bummer was BC,  It was so close to blooming

[luthienj]

An update on my infected seedling:

I rinsed all the old soil off, rinsed the roots in bleach water and pruned away any roots that were not healthy looking and repotted in new soil with beneficial fungii in a sterilized pot. That was over 2 years ago!

The plant is still alive and doing well (there are pictures of it in the NYC garden), although it is very sensitive to full afternoon sun, as if it never quite fully recovered. Sadly, I have not gotten any blooms (or even buds) from this seedling. I am now trying to root several cuttings and to graft a branch onto one of my healthier plants so I can see what kind of flower I might get.

(As an aside, I find rinsing the soil off to be pretty tedious if you don't have a sprayer on a hose. I found it was quicker to use a fork to get rid of most of the soil, but you have to do it before getting it soaking wet. Once the soil is soaked it really clumps onto the roots.)

Wilt disease is quite scary and is a real problem for those of us in the North. I lost my Bluebird to wilt suddenly this year. Spider mites had weakened it and then one day it was wilted and the next it was dead. I opted not to try to save it in fear of spreading disease to my other plants and because I found the plant to be leggy and extremely prone to spider mites.