Snow cover before winterizer.

[PSU4ME]

Not sure if this issue will present itself but it’s looking like a possibility for us in the New England area. We got more snow than expected, it’s not melting as fast as I would like and I just saw a forecast that said 3-5” of snow is possible Tuesday. Temps are not going to be favorable for melting either.

So the issues I see are:
1. Can’t tell when grass stops growing. In the next week or two is my estimated range.
2. Without my winterizer down, I’m not ready to throw in the towel for the season. If snow remains and the ground freezes too much, am I SOOL or is there a recommended way to winterize with snow on the ground (only about 1-2” now.

Thanks

[FrankZ]

I've been wondering the same thing.

I don't see why we cannot drop it on the snow covered ground. As it melts, it will break down into the soil provided its not frozen.

The questions we will get from neighbors when they see us with our spreaders will be priceless

[Green]

Same forecast here. Never had to deal with this before.

As far as the top layers of soil freezing, I would think they would tend to unfreeze as the snow melts. But I guess the window for winterizing might be much shorter. This is probably one of those legit cases where using soil temp is a huge help.

Just as important, I and I'm sure many of us, have a sandwich of leaves, snow, more leaves. The grass is also matted, so it will be hard to tell if it's growing.

[seiyafan]

I will skip winterizer this year, it's grass after all, not rocket or drug.

[Green]

I am not skipping, unless I'm absolutely forced to by weather. I've only put down 2 lbs or so of N so far this year on most areas.

[turf_toes]

If you try fertilizing on top of snow, a good deal of it may wash into the watershed leading to algae blooms.

I’d not do it or suggest anyone else do it either.

[Dargin]

Seems like doing this would make it difficult to control the distribution of urea. I imagine scattered pockets of pooled hot spots as the snow melts. Even if that caused no damage it would still probably be a less than effective app. I don't know from experience, could easily be wrong, but my gut is telling me it's a bad idea.

[andy10917]

^^^ Agree 100%.

[southern-ct-4]

... This is probably one of those legit cases where using soil temp is a huge help.

What are you looking for in terms of soil temps to help determine if growth has stopped (or that it's otherwise an ok time to put down the final urea app)?

Fortunately, for me, it looks like Weds/Thurs/Fri should be dry, and I'm hope the rest of the snow melts today/Tues/Weds, so I should be able to put down my winterizer Urea Thursday or Friday morning (and then rain is coming Saturday).

I'll mow/bag/look for clipping assuming snow has melted and lawn is otherwise dry, but if it's not, is there a particular soil temp that will give me a good enough 'go ahead' indicator to put down the Urea? I'm using 10/21 or so as my avg first frost, so I think I'm now bumping right up against the outside range for my last application and, like many of you, the weather has been awful and I can't tell if growth has stopped...

Thanks.

[Green]

What are you looking for in terms of soil temps to help determine if growth has stopped (or that it's otherwise an ok time to put down the final urea app)?

It's not a hard and fast rule, or anything (I've even had very slow growth continue past Christmas some years, or restart during a warm week in January), but in general, top growth stops (or at least drastically slows) under 40F. So that's the upper bound I'm looking for. At the same time, 32F means the ground is frozen, and frozen ground is not what you want for putting fertilizer down...it will likely run off, and the grass can't use it at all anyway...which is bad for the waterways. So, I'm looking for something between 33F and 40F, but probably closer to 40.

In past years, the temps and growth lined up with each other pretty well.

Mowing is not going to tell me if growth stopped this year, since it's all matted down now. So, I'm only going by soil temps because I have no other choice this year.

Also, I want to be clear, when I talk soil temps, I mean temps I've measured myself. Websites aren't accurate in my experience.

I'm really close to the winterizing window now, and all indications are that it's going to be a shorter than average window this year where I am.

[southern-ct-4]

Ok gotcha. Greencast puts me at:

Current Soil Temperature : 43°
24-Hour Average : 46.7°
5 Day Average : 36.4°

but I believe I have a thermometer somewhere and will see what it says.

In any case, I think I'm ready to apply the Urea and will do so end of the week (if not sooner).

Thanks again!

[turf_toes]

Soil temperature sites are a solution looking for a problem. If you can’t see the grass because it snowed, you missed your window.

Putting fertilizer on top of the snow is irresponsible.

If the snow melts, you can try testing with a soil thermometer. But relying on a website to tell you will be hit or miss. Save yourself some time and flip a coin. It’s got almost as much chance of being right as a website which can’t take your local variables into account.

[Green]

Ok gotcha. Greencast puts me at:

No, no, no! Don't use that for more than entertainment or curiosity! It's never been right for me, lol.
Nothing against it...Syngenta is a wonderful company. They just can't know your yard/neighborhood as well as you do.

Like Turf_Toes says, use your own thermometer if you have no other choice, which is what I did.

[southern-ct-4]

Understood, thanks!

[Green]

Ok gotcha. Greencast puts me at:

But maybe you were just curious. I can't tell you how many people go by those sites, though. The worst is when they think they missed their window because the site says 32 degrees, but in reality, their yard is considerably above 32. I don't even want to know what it says for my area, lol...

[Maizan24]

Looking like I MIGHT be able to get in a mow this weekend. Hoping it's the last because I kind of just want to get my winterizer down and be done with it. Last mow there was still about .25 to .5 inch clippings. Well see how it all works out.

[Green]

Looking like I MIGHT be able to get in a mow this weekend. Hoping it's the last because I kind of just want to get my winterizer down and be done with it. Last mow there was still about .25 to .5 inch clippings. Well see how it all works out.

I think it will work out for us. The last bit of my 10 inches of snow will be melting tomorrow morning (I helped it along today using a shovel and broom). Though the ground is still saturated, I plan to pick up or mulch leaves tomorrow, and then do my final mow and winterizer on Saturday. Right now, the grass is frozen solid, and I had to scrape ice off my windshield around 8PM. It was 33 degrees outside!

[BobL]

I highly recommend a soil thermometer - $17 at Amazon - https://www.amazon.com/Vee-Gee-Scientif ... 07BSSZX1C/

I've periodically look at Greencast and the NRCS Soil Temp graphs - the correlation to my own data is decent but nowhere near perfect. After 10+ years, I have a pretty good handle on how various growth events relate to temps on my specific lawn.

I wouldn't put fert down on top of snow because, at least where I am, the snow will surely melt in a day or three. It's extremely unlikely that the ground is "frozen" just because it has snow on it. Mine is at 42 right now, we've already had 2 measurable snows, and it won't actually freeze for 4-5 weeks. Waiting a few days and putting it on the grass is highly preferable to putting it over snow today, IMHO.

[Green]

I highly recommend a soil thermometer - $17 at Amazon - https://www.amazon.com/Vee-Gee-Scientif ... 07BSSZX1C/

I slightly cracked the face (where the writing is, not the glass), and bent the stem, on my all-purpose thermometer by pushing it into hard ground the other day. The one you linked to claims it's a soil thermometer, but looks almost exactly the same. Do you think it's more robust than a standard model? I'm a bit dubious.