Lawn fungicide that is safe for palm roots

[Christopher Dillman]

My fescue lawns have come down with a fungus that needs to be sprayed. I do have nearby mature queen palms, with roots that extend underneath these lawns.

I'm reading even the organic lawn fungicides kill both harmful and beneficial fungi in the soil.

My initial reaction is to skip the fungicide before I lay down the new top soil and grass seed in order to protect the palms, and just take my chances.

However if anyone knows what I should look for in a fungicide that would be safe for palm roots? If you have a brand recommendation that would be even better. Thank you.

[happypalms]

You can use Mancozeb on turf. Also great for killing mites. 

[Harry’s Palms]

For a brief period of time after buying our new home , we had sod and I used a Scots product that kept everything nice but I can’t remember which one. Go by what Richard recommended, he knows this stuff. I ended up pulling out all the fescue and replaced it with beach pebbles and wood chips. Harry

[Christopher Dillman]

7 hours ago, happypalms said:

You can use Mancozeb on turf. Also great for killing mites. 

Thank you! I'm based in Southern California.

Quick Google search tells me the EPA is looking to ban Mancozeb in the US. Wonder why?

[happypalms]

2 hours ago, Christopher Dillman said:

Thank you! I'm based in Southern California.

Quick Google search tells me the EPA is looking to ban Mancozeb in the US. Wonder why?

Yep ban it, it kills fish if it gets into waterways, and causes birth defects no pregnant women are allowed to work in the horticultural industry where it is used, and it gets into the endocrine system. I think that is a valid reason. Yet in Australia we pour it all over our fruit trees! Banned in Europe as well! 

[happypalms]

Just now, happypalms said:

Yep ban it, it kills fish if it gets into waterways, and causes birth defects no pregnant women are allowed to work in the horticultural industry where it is used, and it gets into the endocrine system. I think that is a valid reason. Yet in Australia we pour it all over our fruit trees! Banned in Europe as well! 

Ps look for something that has the same active constituent if you don’t want to use mancozeb! 

[SeanK]

1 hour ago, happypalms said:

Yep ban it, it kills fish if it gets into waterways, and causes birth defects no pregnant women are allowed to work in the horticultural industry where it is used, and it gets into the endocrine system. I think that is a valid reason. Yet in Australia we pour it all over our fruit trees! Banned in Europe as well! 

Hmmm. If the EU bans it, we in the US usually go double-dose with it. 

[happypalms]

18 minutes ago, SeanK said:

Hmmm. If the EU bans it, we in the US usually go double-dose with it. 

Yes Monsanto and Dow Corning, running the globe. Just look up Bopal in India and the chemical disaster they had. The US bans it then Australia gets dumped with it! 

[SeanK]

1 hour ago, happypalms said:

Yes Monsanto and Dow Corning, running the globe. Just look up Bopal in India and the chemical disaster they had. The US bans it then Australia gets dumped with it! 

It's a cold day in h*ll when the US actually bans something. The EU won't even feed our food exports to it's dogs.

[happypalms]

24 minutes ago, SeanK said:

It's a cold day in h*ll when the US actually bans something. The EU won't even feed our food exports to it's dogs.

Yep too right, and that ain’t going to freeze anytime soon. 

[Harry’s Palms]

I really don’t want to rant , but a lot of what you guys are saying is correct . I know from the short period of time that I had Fescue lawns what it takes to keep them nice. Those beautiful green golf courses are chemical nightmares. The run off from massive amounts of chemicals and irrigation , and some of ours are right next to riverbeds that flow to the ocean . One of my surfing buddies collected samples for Surfrider Foundaion and found high , unacceptable content at most of our beaches here. The ocean is unsafe for surfing or swimming at least 3 days after a rain event . OK I’m done , back to palms again!🙂 Harry

[happypalms]

11 hours ago, Harry’s Palms said:

I really don’t want to rant , but a lot of what you guys are saying is correct . I know from the short period of time that I had Fescue lawns what it takes to keep them nice. Those beautiful green golf courses are chemical nightmares. The run off from massive amounts of chemicals and irrigation , and some of ours are right next to riverbeds that flow to the ocean . One of my surfing buddies collected samples for Surfrider Foundaion and found high , unacceptable content at most of our beaches here. The ocean is unsafe for surfing or swimming at least 3 days after a rain event . OK I’m done , back to palms again!🙂 Harry

You know what’s the scary part Harry, as I read your post iam spraying the blueberries with mancozeb as I type, when I say trust me I know how much of it is put on our fruit! Go organic fruit as much as possible, I don’t eat blueberries anymore let me say that, i buy organic fruit only and I wash that as well. Our planet is not going to continually take this much chemical abuse and not have a reaction in the long run. And the saddest part is it’s all for profit. It’s bad enough our palms are being threatened by habitat lose animal extinction…….

Richard 

[Harry’s Palms]

My Belmoreana has scale right now so I manually washed the fronds with dish soap and a rag. It came back so I had to use a mild pesticide( not sure what , but supposedly safe around pets) . Usually soapy water works and always my first choice. It does well against mealy bugs and mild scale . Harry

[Christopher Dillman]

On 7/2/2025 at 1:58 PM, happypalms said:

Ps look for something that has the same active constituent if you don’t want to use mancozeb! 

Pardon that I'm bit of a noob here when it comes to fungicides.

What would that active constituent be that I should look for in US products? Thx!

[Looking Glass]

Antifungals would have a low potential for direct harm to palm trees when the instructions are followed.  If you are having a fungal issue in your lawn, I’d look at your lawn’s growing conditions first, in conjunction with the type of fungus you are trying to treat.    

Are you irrigating in the evening, instead of the AM, leaving the grass surface wet all night?  Are you irrigating too often or too much or even too little at the wrong time?   Is there a shade issue causing grass thinning or excessive surface moisture?   Is there a pest issue or dry spots mimicking fungal damage, when something else is actually the cause?  Is the lawn be fertilized too much or too little?  Is there an excessive leaf, flower of fruit drop from nearby trees?  

Fungal spores are ubiquitous in the environment and it’s the conditions that allow them to come to life and flourish

Are you trying to treat brown patch, grey leaf spot, red thread, powdery mildew, or dollar spot?  Or something else?

Pick a directed anti-fungal if needed, but adjust care practices to minimize fungal growth as the priority.   

Finally, I’d assess various areas of the lawn to see if grass is actually appropriate there, if you have shaded areas, dry pots or other problem spots, consider getting rid of the grass in those areas and replacing with rocks, shrubs or other ground-covers.  

I personally don’t love using antifungals around my palms, as there is a theoretical chance that you could disrupt beneficial micorrhizal root associations.  But, I have used them here and there, when I first got the current house.   The cure for many fungal lawn issues, long term, is fixing the cause though, and now I find myself not needing them in recent years, as overall care got dialed in.  

Most, if not all antifungals are safe, just not ideal, for palms.  

 

[Christopher Dillman]

6 hours ago, Looking Glass said:

Are you irrigating in the evening, instead of the AM, leaving the grass surface wet all night?  Are you irrigating too often or too much or even too little at the wrong time?   Is there a shade issue causing grass thinning or excessive surface moisture?   Is there a pest issue or dry spots mimicking fungal damage, when something else is actually the cause?  Is the lawn be fertilized too much or too little?  Is there an excessive leaf, flower of fruit drop from nearby trees?  

Are you trying to treat brown patch, grey leaf spot, red thread, powdery mildew, or dollar spot?  Or something else?

Thank you for your questions, and I appreciate your primer on antifungals!

Tbh I have not identified the fungus, other than it got to the point of the lawn not flourishing anymore on the current water schedule (PM - 2 days a week, 17min ea). Still lots of dried up patches, no matter how much I aerated. Nobody's fault but mine - I whiffed on a year or two of no fertilizing, thatching, and seeding. 

Might be good to get a soil test and see if anything funky comes up.

Type of grass? Also a mystery - my landscaper (who I paid to do it decades ago) has never got back to me on type. Best guess - a fescue for SoCal. And I'm hearing fescue is no bueno for summer months. Bermuda or buffalo grass might be the way to go - I have to do more research on it. 

Without being able to identify the fungus, I'm wondering if there is an 'all-around' preventive for current and future collection of fungus. If not, I'll just roll the dice with my current lawn revival plan. Lots of dethatching, repairs with top soil, overseeding, peat moss, liquid chelated iron, and prayers. 

[happypalms]

8 hours ago, Christopher Dillman said:

Pardon that I'm bit of a noob here when it comes to fungicides.

What would that active constituent be that I should look for in US products? Thx!

 

[Looking Glass]

4 hours ago, Christopher Dillman said:

Thank you for your questions, and I appreciate your primer on antifungals!

Tbh I have not identified the fungus, other than it got to the point of the lawn not flourishing anymore on the current water schedule (PM - 2 days a week, 17min ea). Still lots of dried up patches, no matter how much I aerated. Nobody's fault but mine - I whiffed on a year or two of no fertilizing, thatching, and seeding. 

Might be good to get a soil test and see if anything funky comes up.

Type of grass? Also a mystery - my landscaper (who I paid to do it decades ago) has never got back to me on type. Best guess - a fescue for SoCal. And I'm hearing fescue is no bueno for summer months. Bermuda or buffalo grass might be the way to go - I have to do more research on it. 

Without being able to identify the fungus, I'm wondering if there is an 'all-around' preventive for current and future collection of fungus. If not, I'll just roll the dice with my current lawn revival plan. Lots of dethatching, repairs with top soil, overseeding, peat moss, liquid chelated iron, and prayers. 

You could probably head down to Lowe’s and get Scott’s Disease Ex or BioAdvanced Fungus Control for Lawns, if you want to just throw something down and see what happens.   I wonder if it’s just your fertilizer or watering that needs attention, or if you have grubs or army worms of whatever pests plague you there though.

Proper diagnosis and targeted treatments work best though.  

I had a lot of problems with fungus and many pests in the lawn at first here.   It took me a couple of years to figure out the right water and fertilizer combo, through trial and error, and how to adjust for the ever varying weather cycles.   Now I rarely treat for that stuff anymore, as the grass is healthier and stronger, and tolerates various insults more easily.  When the lawn was in a weakened state, it was easy for just about anything to tip it over, early on.  

Maybe snap some pics and head over to the lawn forum for more expert advice.   Those guys are more crazy about perfect grass carpets, than they are here about palms.   They are neurotic nuts, that have things down to a science for grass. 

Weeds still plague me sometimes, as they are very aggressive and can move a foot a week here, and I hate treating for weeds.  Overall, lawns are in PIA.  I’m slowly phasing more and more of mine out.  

[Christopher Dillman]

12 hours ago, Looking Glass said:

Maybe snap some pics and head over to the lawn forum for more expert advice.   Those guys are more crazy about perfect grass carpets, than they are here about palms.   They are neurotic nuts, that have things down to a science for grass. 

Thank you! I do like the BioAdvanced products.

Is the lawn forum here somewhere within Palm Talk, or somewhere else? Link is appreciated, thanks!

[Looking Glass]

On 7/10/2025 at 1:17 PM, Christopher Dillman said:

Thank you! I do like the BioAdvanced products.

Is the lawn forum here somewhere within Palm Talk, or somewhere else? Link is appreciated, thanks!

There’s forums for everything out there.  I’ve gotten info on various lawn forums for different issues just by reading pertinent threads, but I’m not subscribed to any specific one.  That, and Reddit, are like the old way of asking your neighbor or the guy at the hardwear store for advice in the pre-internet days.