Question
just got new grass three weeks ago and is turning yellow, i went to star nursery and they told me i have fungus,what do i have to do to make my grass green?

Answer
I know what YOU did, Adrian.  You picked up a bag of Scotts New Grass Fertilizer and Weedkiller, right?

Because you are responsible!  Because you take care of these things!  Because you LOVE your Grass!

Right?

Adrian, IF Star Nursery is right, IF you have a Fungus, it was caused by the Scotts fertilizer.  Hard to believe.  But true.  Let me show you how that happens.

Our soil is FILLED with Fungus spores.  Our air is FILLED with Fungus spores.  As I typed here, Adrian, I am breathing them in.  As you read this, Adrian, you are breathing them in.  Fungus and Mold spores are microscopic little dots that we can't see or smell or feel.  But they are definitely out there.  They're waiting for your kids to drop a towel on the bathroom floor, and leave it there for a few days.  They're waiting for someone to keep bread in the refrigerator too long.  They're waiting for the Fruit Basket to sit a few days and not get all eaten.

They're also waiting for your Grass to get wet and grow too fast.  BUT that's not enough!  Because outside, BAD FUNGI are a VERY small number.  MOST FUNGI IS GOOD FUNGI.  It decomposes wood, it breaks down organic matter, it turns dirt into soil.  And Good Fungi has one more job: It keeps BAD FUNGI from getting too strong.

How?

Two ways.  Good Fungi is all over the place.  If it's already there, there's literally NO ROOM for BAD FUNGI.

That's the first way.  The second way has to do with the way some Good Fungi actually compete against Bad Fungi.  If Bad Fungi are too busy scrambling for their lives, trying to get by in this cruel world, YOUR GRASS IS THE LAST THING they have to worry about!  Bad Fungi are too busy trying to avoid the Good Fungi.  And while we don't have Good Fungi Protection in our house, we have them guarding our Soil.  And they make sure the BAD FUNGI keeps a low profile.

But Adrian, when you put down Fertilizer and Weed Killer, Adrian, my friend, you wipe out the Good Fungi.

So sad.

Now the Bad Fungi are here.  There is no one to protect the Grass.  So they looked at your Grass, which was growing too fast on top and too slow on bottom (roots) because you put down Scotts fertilizer.  When you watered the Lawn -- at night? -- and gave them moisture (in the dark?), they moved in, drew their pistols, and said to the Lawn, 'Stick 'em up!  This is a holdup!'  And they robbed your Grass of nutrients, and then they took out their guns and started shooting.  And some of your Grasses were hit, and turned Yellow.

If you want to save your Grass, and if this is a Fungus, you should STOP watering your Lawn all the time.  It's new Grass, but at day 7 you should be watering less than once a day, and by now you should be watering only when needed.  NOT for the fun of it!

Tell me more about the shape and size and color of the Yellow, and I'll tell you more about Bad Fungi.  Depending on what kind of Fungus you have, you have different treatments open to you.  Whatever you do, Adrian, don't use a Fungus killer.  It will destroy all the Good Fungi that are coming back.

Tell me more about your Yellow Grass disease.  I'll be watching for your question.

I would appreciate your rating me when you are done here.  That way I can be listed on the AllExperts of the Year at the end of the Year.