When in doubt - check www.solutionsforyourlife.com
Enter your problem - Ixora diseases - in the search box and see what you find .
Flip the words around or use different words and you get totally different results .
My guess ? Aphids - spray with soapy water . Safe , effective and cheap .

Shelbey,
As long as you are OK with me guessing, I have a suggestion. On fruit trees, that sooty mold is controlled by using a fine oil spray that coats and kills the insects that cause it. I would try that. One of the popular and easy to find oil sprays is called Volk Oil, but any horticultural oil should work. You should be able to find it in any big box store or nursery. I don't believe it would present any health issues to your children, but certainly read the label before you buy it.
When I use it on the citrus trees I see clean, new leaves within a very short time; 7-10 days. It won't remove the mold from the current leaves but new leaves should be fine.
Be sure to spray it so that the underside of the leaves get coated too!

Kate

Sooty mold is usually associated with an insect infestation - commonly scale, aphids or mealy bugs. The insects secrete honeydew which the mold grows on and causes the black on the leaves. If you fertilize the plants regularly there is a good chance you will not have this problem, however you need to use palm/ixora fertilizer - plenty of it and regularly. It will take a few months before you see any improvement and in the meantime you can spray with oil or you can try blasting off the insects and mold with the hose but this is a bit time consuming. Regular fertilization should eliminate the problem.

If oil spray is used to get rid of the infestetion,the ladybugs wich are the good guys eating the honeydew,would they be harm also? Just wondering because I sometimes have that problem with my citrus.
Felix

I've never heard that the oil is harmful to ladybugs. I believe it works more as a coating on the tiny aphids that inhibits their respiration and not so much as a toxin. It wouldn't have as much of an effect on larger creatures like ladybugs. Plus they can just fly away when you spray. Of course, if the aphids aren't there, the ladybugs won't need to be there either.

It's interesting to read that regular fertilization would eliminate aphids and other insect infestations. How does that work? I would think that the healthier and better fed the plant is, the happier it's visitors and parasites would be. No? It's not like sitting down to a really nice dinner as compared to fast food?

Kate

Solstice- I think what happens is that a healthy well fertilized plant does not easily succumb to insect infestations and it is the honeydew produced by the insects that the sooty mold grows on. If you get rid of the insects you get rid of the mold - now you could get rid of the insects with insecticidal soaps, oil sprays etc and that is what shelrose could do, but if she then proceeds to fertilize regularly she will probably not have the problem again.
I realize that the insects probably enjoy a nice healthy plant but from my experience healthy plants do not get infested with insects and then sooty mold, and to grow ixoras well you need to fertilize them. This works with gardenias as well-scale and sooty mold can be a big problem with a gardenia but if you fertilize and water them regularly you eliminate the problem.
I am not sure why but I know that it works!
Shelrose, if it were my ixora, I would examine it closely to see what insect I was dealing with and I would try and blast them off with the hose, then blast off the sooty mold with the hose or rub it off by hand(a bit of a job and you might need to do this a few times)-if you have a lot of sooty mold it is interfering with the plants photosynthesis(this leads to a weaker plant). If you can't get rid of the insects with the hose then try oil or an insecticidal soap. Then I would fertilize regularly, with a palm/ixora fertilizer.

Thanks so much for these suggestions-- they are a lot more useful to me than going straight to malathion [which one gardening/extension site suggested, I think]. I have some palm/ixora fertilizer, but I don't think I apply it often enough. I tend to pay more mind to my veggies & backyard flowers. Gatormom, thanks for pointing out that site on solutionsforyourlife.com-- I hadn't seen that, and it will probably help me with a few other things!

Best, and thanks again,
Shelbey

I use pool chlorine mixed in water and srayed on the plants, leave on a few mins. and rinse off, does not hurt the plants, but kills mold and bugs..