NY metro area, zone 7b.
New sod last fall, I’m told it is a mix of tall fescue and Kentucky bluegrass. It’s been growing like crazy lately and looks green and lush before I mow. After mowing it looks yellow, as shown in the photos.
Blade – Freshly sharpened before this mow. It's a mulching blade (MaxPower 331387XB) but I bag the clippings.
Deck Height – That mow was on setting "E" which google suggests is ~3.25 in. Previously I've mowed at the two higher settings, both of which show similar yellowing while also not cutting as evenly – the grass doesn't lift where the wheels went on the previous pass.
Frequency – I wish I had the time. It did look better in the spring when I was mowing every 3-4 days, but I've got a newborn now and I can only get out there once per week lately.
by stayfroggy
25 Comments
Don’t mow more than 1/3 off
Mow more frequently. The bottom part of grass blades are not as green, or yellow, so when you cut 60% off in one mow you expose that. Cut more often and less per
Mow (30% of a blade) then it wont look like shite
Toro
By the look of pic 3, I would guess a mild fungal infection
Check and sharpen your blades, and don’t cut off too low.
Set your deck height a bit higher (or mow more often, but short grass is harder to keep than 3″ grass) Fescue and KBG will do great at taller heights 3-4″
Are your blades sharp? Cut more often. Looks like it’s not cutting so much as it’s mashing it down.
Sharp blades, no more than an inch removed at a time. Cut every week minimum. If it rained a lot between cuts, then try cutting every 4 days.
**Deck Height** – That mow was on setting “E” which google suggests is ~3.25 in. Previously I’ve mowed at the two higher settings, both of which show similar yellowing while also not cutting as evenly – the grass doesn’t lift where the wheels went on the previous pass.
**Frequency** – I wish I had the time. It did look better in the spring when I was mowing every 3-4 days, but I’ve got a newborn now and I can only get out there once per week lately.
**Fungus** – I was wondering about this. Is this something I should treat now or in the spring?
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Cutting too short. Set your deck to 4″. Mow more often as well..
God damn she thick (Tpain voice) as others said mow more frequently. No way around it.
It looks greener before you mow because the green grass grows up and blocks the view of the yellow grass. If you want it green after you mow it, you should mow it one or two knotches shorter to mow the yellow grass shorter. The next week raise it back up to your desired height, it should look perfect after a couple weeks.
Basically cut too much this time~the lower part of the grass is not green, especially the crowns, they elongated to support the taller blades when the grass is tall.
Your grass could be showing signs of stress by losing too much of leaf, but they will bounce back, potentially faster with care. Water adequately, and watch out for fungus since they’re vulnerable now. Wait for the signs of recovery before fertilizing, otherwise the fertilizer could damage the grass that hasn’t healed up the cuts
Measure your grass after you cut, wait a week (since that’s how often you’re getting to it) and measure how much it grew. Divide that by .3 and you’ll now know how tall the grass needs to be before your weekly cut so that you’re only taking 30% off max. Could mean you need to raise the blade so you’re not taking half of it off or more during mowing
I’m calling grubs!
It’s just for cutting too much off at once. I just did this to my yard cause I had to lower the height to over seed. It all came back and looks normal again. Give it a week or so and I bet it will be back to normal
Cut more often. The bottom area of your grass will be more yellow nearer the roots and they also get less sun. If your grass bounced back and is growing well this time of year out of the summer heat, you could mow even shorter as kind of a reset, let it grow, then go back to cutting at your regular height to get the green lower down.
Im no expert, just reading thru everything, seems cutting too much off at one time exposed the yellow stalks. I have seen the shorter days of fall and cooler temps will make grass go dormant, but not the Kentucky bluegrass…. (I just aerated and re-seeded). Overall, I don’t see any weeds (that’s good) and you should easily be able to lift up an area to see if you have grubs. That’s my two cents 😉
The top of the plant is greener than the bottom. If you mow frequently at that height it’ll look better
Piggy backing on OPs post, am I helping my lawn if I go around picking out the dead dead bits by hand? For context I’m a couple of months into actually trying to care for my lawn, went about 2 years of not doing anything at all besides mowing when it got unruly. And when I say dead dead bits there like solid brown. Some of the lawn is brown under when I brush my hand through it but the tips are green so I assume those are alive and like what people are saying about OPs to mow more frequently and that’ll go away eventually.
Edit: forgot to mention it’s Bermuda grass.. so my thought process is if I’m pulling what I’m perceiving as completely dead grass it’ll open up space for the growing Bermuda to take over. Thanks!
Looks like your blades might be dull
Agree with others. The more sunlight the lower parts of the blades get, they will green up some. Just be consistent. mow more often and at a higher height.
I do weekly at 3.5 no matter what the growth. Your grass is healthy, it will adapt.
Also your note about the grass not popping back up where the wheels go. Mine does this too, so when I make the next pass I don’t put the wheels in the exact same path I sort of overlap the paths by a few inches.
Did you sharpen it correctly? There’s a lot of shredded leaf tips that I can see
It’ll look good in a week or so.