Delton,
I used the standard granular fungicide for lawns that comes in an orange bag from Home Depot.

Any open mouth gasping going on?

Thanks. So you just followed the dosing instructions on the bag? Would this be something to use on all the plumies as a preventive measure? I'm getting several cuttings and some are mentioned as being prone to black tip.

Delton

I use Phytosan which is a liquid.

I have a Madame Poni that had a damaged tip last year, but it is doing okay this year. I think I sprayed it this year, just in case. ;) It has yet to bloom.

You might wish to consider Tebuconazole, a broadly effective systemic fungicide that can be found widely for over-the-counter sales. It's available in Bayer Advanced Disease Control for Roses Flowers and Shrubs.

It's also available in Bayer Advanced 3-in-1 Insect, Disease, & Mite Control, which includes a systemic insecticide (imidacloprid) and a miticide. Often, thrips or other insects with rasping/sucking mouth parts act as vectors for fungal infections.

Spray only outdoors and on days when you suspect the next day or two will be cool/cloudy or overcast. IOW - don't spray when hot sunny days are in the forecast, or move your plants to shade (if possible) before you spray.

Best luck!

Al

I believe research has shown that black tip is not caused by fungus, but by plant stress (caused by too long a dormancy, too cold temps, frost) or by sucking insects at the tips (mites, etc). Therefore fungicide will not prevent it. However, it may help prevent outbreaks of rust.

I like Al's suggestion of a systemic which can possibly reduce mite, thrips and other pest populations.

If I see black tip, it's usually because my plants are bothered by mites, or because they are being stressed in the late winter as they try to come out of dormancy because temps are not warm enough.

I was going to mention that googling around I found an article by Jack Morgan that says that there is no evidence, as you say, that fungus is the cause of black tip, rather environmental stress. I put the link below.

Here is a link that might be useful: Cause of Black Tip

Thanks Al,

I think that Bayer 3-in-1 sounds like the way to go, pretty much covers all the bases. Thanks for your info.

I steer clear of anything containing imidacloprid on my plumerias. Its notorious for causing future problems with spider mites. You may want to research it a bit more.

Thanks kms2. Any reason why it would increase spider mites in the future? Maybe killing off their natural predators?

I found an item that said it turns off some genes in some varieties of rice that produce defensive chemicals and makes them more susceptible to certain rice pests. Could it be something along those lines?

There is some evidence that some nicotinoidal insecticides, among them imidicloprid, may increase fecundity in some mite species at less than lethal dosages. I think you need to balance that against the fact that it's long been recognized that virtually all broad spectrum insecticides that aren't effective on mites have the potential to increase mite numbers, mostly the contact topicals (Sevin, malathion, pyrethroids, .....) because they are equally hard on mite predators, whereas imidicloprid primarily targets insects with rasping/piercing mouthparts, not predators. In addition, you have to have a preexisting mite population before fecundity can become an issue, and it's also a consideration that the 3-in-1 product contains tau-fluvalinate, an effective miticide.

Anyway, you started out looking for a systemic fungicide, so if you decide against the 3-in-1 based on what you discover, the tebuconazole is still available w/o insecticides in the Bayer Advanced Disease Control for Roses Flowers and Shrubs.

FWIW, I've used various products containing imidicloprid on hundreds of species of containerized plants since the mid-90s, and have never noticed a higher incidence of mite infestations on the plants I've used them on as opposed to plants in the landscape, but that observation should be taken for what it is - anecdotal.

Al

Thanks for that information, Al. I really appreciate your input. The details you provide are very useful to understand exactly what I need vs reading it off of a label on the bottle. Thanks again.

Thank you very much, I appreciate your saying so. It goes w/o saying though, that reading the label carefully is an important part of using any insecticide or horticultural chemicals - for the well being of the grower as well as the plants. There is always some risk involved with almost anything we might use to kill insects or thwart diseases, and we can minimize risk by only using these remedies judiciously and responsibly.

Plants mount a number of genetically encoded responses to the wounding of insects or the chemical signals released by disease, ALL of which require energy allocation. In plant cells, there are genes that control proteins functioning in actual defense, sending defense signals (chemical messengers), altering metabolism, controlling cellular maintenance, regulating photosynthesis, - and many more genes of unknown function. In short, plant energy reallocation is prioritized in the plant's own defense, while other things, like every day metabolism and photosynthesis are put on the back burner. The higher the plant�s level of energy (the greater it's vitality) and the faster its metabolism - the faster the response and greater the amount of energy and defensive bio-compounds the plant can mobilize and devote to its own defense.

When wounding occurs (insect attack or disease) there is a "wound response" that occurs both at the site of injury as well as distally (in other plant parts away from the wound). Plants can even differentiate between the wounds of a pin and those of insects, and they react in different fashion to the "attack". Without getting more technical, the plant produces various anti-feedants, anti-metabolites, and toxins that make the insects feel rather unwelcome - as long as the plant is in good vitality or has high energy reserves - in other words, as long as the plant is in good health. The speed with which the response occurs, and the effectiveness of the defense response are also both energy driven, so it should be no surprise that plants grown under stress are highly susceptible to a variety of insect marauders and various diseases.

If you want to keep the bugs and fungaluglies away - consider that your first line of defense should not be to reach for a systemic or other harsh poison, but to keep your plants growing with as much vitality as possible as a preventive measure, which is a cultural - not a chemical thing. It is important to remember that most of the problems we find in plants that involve disease and insect attacks can usually be linked to the reduced vitality and lower metabolism rates resultant of our inefficiency at being able to provide as well as we might, what the plant wants culturally. That's a charge no made from a high horse, because I include myself along with everyone else. There isn't one among us that couldn't afford to learn how to better provide for our plants. That's simply a universal truth that's inseparable from the growing experience. When you think about it, the only way we progress at growing is by learning to identify and eliminate or reduce the effects of the things that limit our plants. The plants know what to do and how to do it - it's in their genetic programming. All we need to do is learn how to keep our practices from limiting them so they can do their thing as efficiently as conditions allow.

Al