Pesticide/Fungicide Recommendations

I’m looking for an all purpose pesticide that’s safe for use on tropicals. I’d prefer something that’s premixed and available at a big box store, but I’m willing to compromise if there’s a good one.

I’ve had issues with mealy bugs and spider mites in the past few years, particularly in my jades, Fukien, and on some rosemary.

I’ve tried one by Sevin for fruits and vegetables that burned the leaves on my Fukien and made my jades drop some leaves. Also killed a big piece of my wife’s roses.

I’ve had other bugs around my trees, but these two have been the destructive ones that get out of hand very quickly.

What do you use on your trees, and in what concentration?

Any fungicide out there that I should be using as well?


Ryan recommended mancozeb fungiside in one of :thinking:the streams. Do not remember which stream, I need to start taking notes!!
product label says: Use 2-5 teaspoons per gallon
• Controls leaf spot, downy mildew, blights, anthracnose, botrytis and other listed diseases
• A broad spectrum fungicide for use on a wide variety of vegetables and ornamentals
I always go light in dosage and it seems to work for me… so 1 to 2 teaspoons per gallon.

I use granular systemic insecticide on my tropicals, and water it in over the fall and spring. Label says it lasts 8 weeks, so I think it knocks down many generations and reduces the population very well. only an old guy experience.


For insects go with a systemic insecticide preferably NOT one containing amidacloprid. I have used Acephate sparingly for years with great results.

For mites don’t mess around with junk like neem oil. You need a miticide. Forbid 4F is great but Avid is also good. Avid will not kill eggs so you need to apply at an interval after those eggs hatch. Forbid 4F will kill all life cycles of mite. Floramite will kill all life cycles too but it works purely by contact. Forbid and Avid are translaminar which is the closest to a systemic that you are ever going to find with today’s modern miticides. Due to the fierce resistance development of mites I would always follow the recommendations of literature which say to rotate miticides with different modes of action so you don’t produce resistant genotypes. The strategy of spraying Floramite then Avid a few days later makes a lot of sense if you think about it. You kill off all eggs by contact then you apply a residual protective barrier to defend the plant. If you spray Avid first you leave eggs alive and by the time you hit them with floramite the residual effect of the Avid is less effective in managing any remaining mites that were not contacted by floramite. Knock them all down with the contact miticide then fight the remaining with the residual as a better strategy. Keep in mind mite eggs hatch in only 3 days so spraying after hatching but before reproduction is key in breaking the mite life cycle. In about 12 days the mites can reproduce again laying as many as 12 eggs/day. If a female mite does not find a male mate she will reproduce asexually and lay eggs that produce only female mites. Repeated applications are almost an absolute requirement for effective mite control. Neem doesn’t kill eggs and oils don’t lend themselves to repeated applications as they also suffocate the stomata.

For fungicides, you either have to identify the fungus or target it with something that has a broad spectrum approach and wish for the best. Ryan recommends Mancozeb for juniper tip blights, Daconil for pine needle casts and cleary’s 3336 (thiomyl in generic form on Amazon which is way less expensive) for leaf curl. Personally I find thiomyl the best for juniper tip blight because it is a systemic and works from within the plant as opposed to mancozeb which kills on contact and requires consecutive applications. The downside being that cleary’s 3336(thiomyl) takes time to absorb through the roots and lamina so take that into account when considering when to apply.

I know there is more I can say about these topics and I’ve only been able to scratch surface at the moment so I highly recommend that you look into the following topics:

Systemic vs contact insecticides
The negative effect of amidacloprid insecticide causing increased mite populations and reproductive rates ( one of my posts on this forum which you can find which is a Newsweek article)
Translaminar miticides
Spider mite life cycles
Any labels to the products I have mentioned and/or all labels of products which you intend to use.
Proper PPE (personal protective equipment) like gloves coveralls and respirators if necessary.
Conditions that are conducive to fungal proliferation and how fungus tends to be host selective

That’s about all I can say at the moment.


That stream was Spring Fundamentals, part of the BSOP series. He talks about it towards the end.


@Bonsai_bob I saw his recommendation on the video, and looked into them. That stuff was a little pricey. I also have all sorts of stuff that I never used, because the trees didn’t react well to it. Kinda put me off on dropping too much cash on something before trying it out. I think I may break down and just get a bottle of the stuff. I’ll look into how well it does on tropicals before, though.

@ChristianReha Thank you so much for the information! I’m definitely going to begin reading the list of topics you mentioned. Also going to look into the Forbid 4F, Floramite, and Avid. The rosemary is the one that gets the mites, and in the past, once one of the rosemary is covered, it dies. Neem oil has always been garbage against them, but whenever I spray the rosemary with anything else, it burns the leaves and kills it. So the mites or the spray kill the plant. Your list gives me choices to try out and it’s exciting!

The mealy bugs have been the bigger problem on most of the smaller trees. The jades seem to be covered spring after spring. I’ve been able to handle them with rubbing alcohol and q-tips, but they always seem to come back. I guess I’m looking for something that will save me the time of going bug to bug with the alcohol.


Acephate should take care of them
for good! As long as the mealy can’t migrate somewhere else and come back when the systemic has worn off. I find systemics work best for these annoying kinds of pests. I would include scale insect in this category as they are protected by a shell which makes contact insecticides effectively useless.


Even though I’m the one who was looking for advice, I think this thread is a good place to mention that BT (Bacillus thuringiensis) is great against caterpillars and other leaf eating insects.

It’s practically harmless to humans, and doesn’t hurt many beneficial insects like bees and ladybugs.

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Thank you for the tip about mancozeb but I have to complain about the lack of Mirai support/video ( for standard members) targeting pesticides and fungicides which is a major subject in horticulture. No point to see long hours of video about design, growing healthy trees when one doesn’t well how to deal with sick trees from pest and fungus.

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I agree that a stream on the subject of disease and insect control would be helpful…
When I searched on the stream for Dothistroma Needle it came up with one stream.
When I searched for Phomopsis blight it came up with two streams. and
Finding the information is not easy! Much of the knowledge I have learned about treating pine and juniper disease has come from Michael Hagedorn. Be a Bonsai Sleuth: What is Needle Cast and What is Overwatering for Pines? | Michael Hagedorn

The information is reinforced by listening to Todd Schlafer and Ryan talking about blight. I vote for a stream to clear up the confusion. The actual disease being treated is problematic. Only a sample studied by a plant pathologist can accurately diagnose the actual culprlt. I usually work on the assumption that the symptoms of Phomopsis and dothistroma are present and the fungicide is pretty broad spectrum.
I have lost several collected yamadori including blue spruce, ponderosa pine and common juniper.
I do not claim to be an authority, but I am learning.


Thanks, Bonsai_bob for the support on this request. Perhaps this post is not the best way to make this petition?
Funny enough when I search for Phomopsis blight just your second link comes up.
Yes, Michaels is also great and although he is very generous with his time answering questions, he seems to be a bit wary on giving this kind of advice as well.
I understand that is a problematic subject but going/paying a plant pathologist is not practical in most cases, so people like me spend a lot of time searching the internet and we all know how frustrating that is.
Besides, it seems that there are just a small bunch of fungicides which treats more than one type of fungus any way!
Plz, Mirai jump into it and really ‘‘break new major ounces’’.

I’ve noticed the hesitancy to advice treatments online and wondered if there were legal repercussions if something goes wrong? Just a guess. In the UK CBD oil can be legally sold as a food supplement for human consumption but the vendors are not able to offer instructions on its use as a medication, could this be something similar? Getting back to trees not all countries have access to the same medications anyway which can be frustrating at times.