Looking for tips and suggestions on killing off mold and fungus in my lawn. This yard was put in about 6 years ago and it was good for 4 years. Then mold started popping up. Last year it looked really bad at the end of the year. It was getting brown patches and died off in big sections. We had the yard thatched this year and removed as much of the old dead stuff as we could get out. Cut back my watering and the yard was really not coming out at all. So instead of 3 days a week 5 minutes a section. I went to 5 days of watering. 2 water days, day off to dry out, 3 water days and another day off to dry out.

Different fungus/mold patch

Lime - and apparently you can't overdo it.

Dig it all out a replace the soil or just live with it, ive one flower bed thats got it six inches deep and it all grows, even shrubs.

What time of day are you watering? What is your soil type? Any shade to contend with?
My impression, you are watering too often, I would go every other day, early morning, and do a deeper watering.
Chemicals are also an option.
But what do I know, I torture myself with a backyard 1000 sq ft putting green, and all I ever do is fight something that wants to kill what ever I try to make green.

Water at 6:30am for 5 minutes each zone.
Started the year watering Mon/Wed/Fri and the yard never greened up.
~6 weeks I went to Mon/Tues/Thur/Sat still didn’t green up much
Then 3 weeks ago went to Mon/Tues/Thurs/Fri/Sat and it greened up quick..along with fungus!

The soil is mostly clay around here.

Try growing a yard in the high desert, I got scorpions in my grass. My sprinklers run about 10 hours a day and the next six weeks its gonna be hard to keep it green. But yet mushrooms grow in my yard.

That all makes sense, and understand, I far from an expert and no experience with clay soils, Fla is all sand. But clay i thought doesn't drain well, and that is a prime situation for fungus. Still my gut tells me you are overwatering, have you tried small amounts of fertilizer (nitrogen) with reduced water to get your expected greening? Does your grass have a natural dormancy season?

Sounds like you're doing a dance between getting your lawn enough water, but starving the fungus. Water in the morning so the top layer of soil has a chance to dry out during the day. Also, I'd consider taking a soil sample and get it analyzed (read up on how to properly take it). They'll tell you what nutrition (and maybe which herbicides) to add. Cost about $20 last time I had it done.

Sort of the same issue I am having. Finally got my lawn treatment people to admit my problem was red thread, which is a type of fungus. Initially they told me the dying grass was because I didn't water it during the hot months. But, based on the sections and where they were in my yard, I didn't believe them. Then this year, they told me I had red thread and said they treated it. It got better in the short term, but it is back again. I have read that treatment only lasts 3 to 4 weeks and needs to be retreated. They have not been back in a few weeks and it is getting bad again. I have since purchased Diseaseex, but have not used it because I wasn't sure when they were coming back. They were in my neighborhood today, but didn't get to my yard. I'm hoping they come back tomorrow because I will be home and can talk to them. Not sure if my problem is the same as yours, but I'll let you know what they say if they come.
Jim

So I can't tell you how to fix your mold or fungus problem, at least not directly, I can make a recommendation as far as using your sprinklers.

I bought my current house 2 years ago, and had never owned a home with sprinklers. I started messing with the sprinkler controller and quickly figured out that it was unreliable at best, I would turn the dial and have to hold it in place, because if you didn't get it just right, it wouldn't work at all.

I started shopping for sprinkler controller replacements and stumbled on Rachio. It is a "smart' sprinkler controller. That thing is AWESOME to say the least. You can install within 15 minutes, you connect it to your WIFI, and then you just open the app and answer a few questions, it pulls data from several thousand weather stations, asks about your soil type, whether parts of your yard are shaded, etc. etc. It then creates a custom watering schedule based on this information, and actually adjusts on the fly per month. You can also set thresholds for when not to water, for instance, if I receive .25 in. of rain, don't water, or if you get winds in excess of 20 mph, or if the temperature drops below a certain degree, etc. The nice thing about this is, it notifies you via the app (and email) when it is going to perform a skip. Obviously, you can override any of these settings or create your own schedule, but it should help take the guess work out of whether you are watering too much or too little. It's also awesome when it is raining, not seeing my sprinklers run, but watching everyone else's.. I just laugh and say to myself "they should have gotten a rachio".

Trust me, they don't pay me to advertise their product, and I'm sorry if I got a little off topic with this, but I figured maybe this would be a suggestion to at least help take a step toward solving your problem.

Let me know if you have any questions!

Do you have any mushrooms growing anyplace in the bad areas?

Have you aerated the soil? The clay gets very packed and I would recommend aeration so the water and nutrients can get into the soil and roots better. Also here is a site that is very helpful about lawns, they have tips, what products to use when, etc.. I bought my sod through them. https://www.supersod.com/