Fung-onil/ chlorothalonil

I was in a hurry to pick up some supplies today and just ran to a nearby hardware store instead of going to the nearest town with big box stores. They didn’t have the immunox I usually use. You know my question:

What are your thoughts on this stuff? Its made by BONIDE, is called “Fung-onil Multi-purpose Fungicide” and is labled for fruit trees. Only 1 active ingredient : chlorothalonil…

If you are familiar with the product, can you also tell me if I’d be ok mixing it with my triazicide .

I’ve already sprayed dormant oil a few weeks ago. This spray will be my first of the year (except the dormant oil) and will be with a day or two of petal fall for most of my trees. I’d like to do the “fung-onil” and triazicide together… What say you folks?

I would like to know how it compares to the commercial product as one member using it for leaf curl reported poor results. Is the concentration the same?
I would not use it for Brown Rot, well it helps, although you need another product as you need to stop using it at shuck split. It’s probably good for shot-hole too. My problem with shot-hole is it looks like fungicide damage from using too much Captan. Then again my leaves had a manganese deficiency at the time, so I have no idea what the holes were? I do know after applying manganese, and my spray program I didn’t have it the next year. Reminds me I need to apply some manganese, It is in low concentration in the native soil.

Oh the concentration of this product is 29.6% Chlorothalonil. If you use a commercial brand could you tell us the concentration and dose? I guess I could look myself…

@Olpea is the expert on fungonil aka chlorothalonil. It has a 60-day PHI which limits its usefulness but is good early in the season for many diseases. It better than Immunox for peaches, its very effective against spot. But neither are good brown rot chemicals if I recall.

@Drew51, shot-hole is usually from bacterial spot. If it is chemical damage the flat spots where more chemical pooled and dried will have more damage.

Yes a third cause of holes. I probably had bacterial spot. I didn’t see it last year, so thankful for that!

Scott’s correct, cholothalonil is a very good general purpose fungicide for early diseases. As Drew points out, the long PHI restricts it to use up to shuck split for peaches. Interestingly it has a 0 phi for tomatoes.

You shouldn’t have any problems mixing it w/ triazicide. I’ve mixed it w/ a pyrethroid before.

As Scott mentioned, Captan burn is more obvious where the chemical pooled. The chemical burns indiscriminately. Bac. spot only knocks leaf tissue out in between the veins. In other words, where it hits a leaf vein, it will stop, giving bac. spot a more angular appearance.

Really good info as at the time I was puzzled. I have to remember this thread if I see it again! I use cholothalonil for tomatoes. When out I want to try Mancozeb instead. I used it for leaf curl the year I got the bac spot, or whatever it was? I didn’t have copper. I have copper now.

Off the top of my head, the only reason I can see to spray the Chlor on fruit is for peach leaf curl during dormancy and for peach scab, maybe about the second week after petal fall (if the label still allows it). So what are you spraying and what are you trying to control? Fungicides are not reliably interchangeable, of course.

Thank-you all very much! Sounds like my unplanned, quick trip to the local store may have left me BETTER off than if I’d gone the traditional BB route and got the usual Immunox! I’ll be applying it tomorrow with some triazicide.

Let me squeeze in one more quick question- when growers talk about spraying “at petal fall” does that generally mean my first spray should begin literally when the petals fall off the bloom, or when the whole flower and “skirt” or “husk” as Drew called it, comes off?

BTW…this thread also taught me what PHI is, though I had to look it up! ha. Now I know its just what us common folk call it waiting period! :slight_smile:
thanks again

Funny you should ask, Alan. I was going to spray Triazicide and Immunox because I have a big thing in the front of my fruit files called “Alan’s Spray Schedule” and it says that after petal fall and bees have lost interest that I should spray those things! :slight_smile: Thats the best reason. But as my post said, I was only able to get the chlor today and was asking if that would be a good substitute.

I used Fung-onil for two consecutive years on my few in ground Nectarines,against PLC and it didn’t help much.
I switched this year to Liqui-Cop RTS(Ready To Spray).I didn’t want to hook a hose to the bottle,but rather poured about 6 tablespoons of it into a gallon of water and applied about 3 times during the dormant season.That hasn’t worked too well either,as a Fantasia has quite a bit of leaf curl on the tips.It was probably in part due to the wettest off season on record.
Maybe it’s also the spreader sticker,Southern AG.I may try Nufilm next year and up the dosage of the Copper.
It will be a good time when I can get the PLC reduced or eliminated. Brady

I used to have PLC. Once I have started using Kocide 3000. That is the end of PLC. You can try one spray before bud break. To be sure, you can add one more spray in late fall.

It help with other problems and you only need to spray once or twice at most.

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Thanks mamuang.Sometimes I’m cheap when it comes to fungicides,pesticides and fertilizers,but I may need to get some. Brady

I use a generic Kocide (actually stronger) and like it a lot. Although I need more time to fully evaluate. Nufilm too very good. The stuff for sure stays on the tree even through rains.


I used to buy quite a few chemicals. Then, I’ve learned about copper. It is a good weapon against fungal and bacterial problems that many fruit trees have, from fire blight to peach leave curl and a few other things in between. I am careful not to overdo it.

Once I’ve realized that Kocide is as good as it gets, I stop looking for other copper. Immunox is good for CAR and scab. These two are what I rely on if I need to spray chemicals.

I have said a few times that NuFilm appears expensive but it really is not. It is worth it especially when the number of my fruit trees keeping going up, not down :smile:

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It is not a good substitute if you are spraying apples and Cornell only recommends chlorothalonil against cherry leaf spot, peach leaf curl, brown rot, blossom blight and black knot ( BK is mostly about plums) and different timing for these is involved.

Myclobutanil (Funginex) is for rust, scab, and mildew on apples and protects against all the diseases on stonefruit that Chlor does besides peach scab and brown rot.

Don’t spray anything but stonefruit with Chlor and go on-line to get the exact timing- also following the label, or tell us what you are gunning for.

Spraying really is something that should be done with care and precision.

I used it the first two years of having apples and it didn’t seem to have any benefit to my trees.

Don’t know anything about how PHI (Preharvest Interval) is determined. It would be useful to understand it. It is band in European Union but ok in US.
With chlorothalonil it can very from 0 (Tomatoes, cucumbers and squash) to 42 days for blueberries and for stone fruit “do not apply after shuck split” and some labels don’t mention apples. I’ve seen “don’t use on apples” some places. Why such a wide range?
I’ve read somewhere it should not be used with oil
I’m using it on tomatoes and cucumbers this year for the first time.