Check This Out, Am I in Trouble

Lows are going to be 34-38 for the next three days and then back up to the 40s. My seeds just started sprouting.

Shoot, root growth will stall below 40 F, but your grass might not survive winter. Germination is more tied to soil temperature (check the automod link). Don’t stress about it. Whatever happens, you’ll get another chance come spring. Just check the soil temp beforehand and plan your seeding right.

@KimberlyMolly
This is the best way to respond to this. A brief cold won’t kill cool season grass… But being too young going into the harsh winter can.

Max said:
@KimberlyMolly
This is the best way to respond to this. A brief cold won’t kill cool season grass… But being too young going into the harsh winter can.

Do you have any links to studies about cool season grass and root growth related to soil temps? I keep seeing 50F mentioned as the cutoff for root growth, but that doesn’t make sense to me. No one ever cites anything, just “oh I read it somewhere.”

@Bao
Cool season grass will grow roots as long as the soil isn’t frozen. When soil temps are over 40F-45F (depends on the species), grass can photosynthesize and create energy. That energy helps with growth. They stop photosynthesizing below those temps, but can still convert some stored energy in the leaves into root growth.

Here are two good sources (both are worth reading for a more detailed understanding):

> Most cool-season turfgrasses produce the best root growth at soil temperatures between 50° and 65°F. When temperatures reach 90°F in the top inch of soil, Kentucky bluegrass root growth is greatly reduced. Cool-season grasses can grow roots at temperatures below 50°F, but the growth slows a lot as it gets close to freezing (32°F).

> C3 plants thrive at 65-75 degrees F. Growth begins when the soil temperature is 40-45 degrees F.

(Cool season grasses are C3 plants) Cool-season or Warm-season Grasses | Forage Information System | Oregon State University

@Bao
I got tall fescue sod installed in December. Then got hit with Arctic air for a week in January. The lawn crew said it was better to do it then so the roots could settle in. The sod did just fine and handled a hot summer really well. I was surprised, but I think the local experts knew what they were talking about.

@Bao
Check out Purdue University’s Turf Grass website. I bet they have info on root growth related to soil temperatures.

Auden said:
@Bao
Check out Purdue University’s Turf Grass website. I bet they have info on root growth related to soil temperatures.

Auden said:
@Bao
Check out Purdue University’s Turf Grass website. I bet they have info on root growth related to soil temperatures.

I didn’t know that kind of website existed. Good to know.

@Dai
Yeah, you’re fine.

@Dai
Looks like my weather is similar, and I have some grass at the same stage. I hope it stays warm for a few more weeks here.

@Dai
You’re totally fine.

@Dai
Where do you live in Chicago?

Cass said:
@Dai
Where do you live in Chicago?

Nah, it must be Ohio. My weather is exactly the same.

Arin said:

Cass said:
@Dai
Where do you live in Chicago?

Nah, it must be Ohio. My weather is exactly the same.

Haha, you got me.

Arin said:

Cass said:
@Dai
Where do you live in Chicago?

Nah, it must be Ohio. My weather is exactly the same.

Yeah, Columbus has the same weather.

Addison said:

Arin said:
Cass said:
@Dai
Where do you live in Chicago?

Nah, it must be Ohio. My weather is exactly the same.

Yeah, Columbus has the same weather.

Glad to find this thread. Exactly what I’m concerned about.

@Dai
You’re golden! :sunglasses:

@Dai
You must be near Cincinnati. I’m close by and have almost identical weather forecasts.

But I’m on the better side of the river.