Fall Nitrogen Regimens

[Tom_SJersey]

Just wanted to share results my first use of organic fall nitrogen, last year. Zone 7a. I did this is a trial and error experiment, Didn't know about this forum, until I joined recently.

1. 2017 - Milorganite, 2x the recommended rate, i.e. 1.728 lbs N/k, applied Friday before Labor Day weekend, steady perfect soaking rain all weekend. Result: iron kicked in within 2 weeks, very solid green. Nitrogen kicked in at about 4 weeks, very solid growth but not the "peak and valley" that I experience with using Scott's in similar stuff previously. A steady good green, and good growth throughout October and up until Thanksgiving. Stayed green until New Year's Eve.

Following spring - Much earlier spring green up than I had experienced before. Always had a difficult green up previously in my yard, this time green up early and solid. Very pleased.

2. 2018 - Switched from Milorganite to OceanGro, similar product made here in New Jersey, about half the price. Applied same time, Labor Day weekend. Similar result as Milorganite, only difference the greening from iron good but not as pronounced, but good. Otherwise the same, very pleased. Good strong growth.

This time, unlike last year, I added a 1.5 lbs N/k Urea application, Saturday after Thanksgiving. Turf still green, could be the weather, could be Urea. Cannot be sure.

I will follow-up in the spring with my impressions of the Urea for early spring green up.

Great forum great advice. Thanks to Andy, and everyone.

[GsdRamsey]

Applied my last Urea the week after Thanksgiving and rain had watered it in. This month of December my area had a few days into the 50's and lots of rain. Will this affect the early spring green up?

[andy10917]

If the lawn had completely stopped its growth, then no - it won't affect it. My lawn has greened-up slightly during warmer/wet periods even in December, but growth has been completely absent.

Did you ensure that the growth had completely stopped (mower/clippings test) before applying the final Urea?

[Green]

If the lawn had completely stopped its growth, then no - it won't affect it. My lawn has greened-up slightly during warmer/wet periods even in December, but growth has been completely absent.

Did you ensure that the growth had completely stopped (mower/clippings test) before applying the final Urea?

Andy, I think "Gsd" may be asking whether the Winterizing app can help with Spring greenup, not Winter greenup. And of course we know the answer to that.

Funny you mention Winter greenup, though. With all the rain we've gotten recently and a bit of warmth at times, days like today--54, for example--I'm noticing some of the sunnier lawns in my neighborhood are actually growing slightly again. And practically every lawn has greened up some.

[andy10917]

I got it and didn't read it as winter green-up -- just saying that if you waited until growth stoppage, nothing will hurt spring green-up, even if you see little hints of greening in the early winter. The first sentence says it all - the rest was just assurance and advice not to be worrying.

[Green]

I didn't realize that's what you were addressing. Anyway, I see it as the lawn trying to photosynthesize, regrow and repair itself at every chance it gets, based on what the current conditions permit, even in Winter if it has a small window to grow a bit.

[andy10917]

I don't see any growth, but I do see some greening. Greening a bit does not seem to indicate a resumption of growth, during Winter.

[Green]

I don't see any growth, but I do see some greening. Greening a bit does not seem to indicate a resumption of growth, during Winter.

I've seen that, too. It may be the chlorophyll changes, or blades that were needled up unfolding again, I guess.

But I'm also seeing slight growth on several lawns that get full sun. Even a bit in my own front lawn...some minor blade lengthening has definitely occurred in the past month at some point.

[GsdRamsey]

I see no growth at all. Does this process of photosynthesis use any of the N that has been stored in the roots is what I was wondering. Thank you all for responding.

[Green]

I see no growth at all. Does this process of photosynthesis use any of the N that has been stored in the roots is what I was wondering. Thank you all for responding.

Even if it does, it's probably not much since it's not growing. Andy's answer a few posts above basically covered it.

[BobL]

Some interesting research around fall fertilization, potentially at odds with existing beliefs/practices. My interpretation is that it may indicate that post-stoppage treatments actually don't get taken up by the roots and sit in the soil until Spring. In sandy soil, it might leech away and have little effect.

My experience has been that if I don't put down the late post-growth treatment, a small (.3-.5 lb) treatment in early spring had the same results.

For comment/discussion.
https://turfnet.wistia.com/medias/yq4djng1cb

[andy10917]

I've done it both ways (I'm always performing experiments), and I have found that it makes a significant difference in how long the lawn can go without fertilization the following Spring. That doesn't mean the research and I disagree in my opinion - in my mind it confirms the importance of the exact timing of the last app. Miss the 2-3 weeks window on top-growth stoppage, and you're wasting your money. I don't measure what's recovered by tests - I measure when I need to pick up the Nitrogen in the Spring, by observing color and health.

So, why do I think that the Doug Soldat talk and my observations are actually aligned? Dig in carefully to what he says starting at 31:55 on the video. In SOIL, he shows at 32:30 that the last application (November in his slide) is actually "money in the bank" (his words), and earlier and better green-up in the Spring, and it stays greener longer before Spring Nitrogen is needed. In SAND (greens), this didn't happen (see 33:50 on the video). I'll restate one of my core beliefs again: treating your lawn as if it were a sand-based green is a mistake (a big one!). Doug says that it's easier to just apply Spring fertilizer in April - this doesn't account (because it's a green) for Spring weeds popping up and you're going to be fertilizing them too with April fertilizer. I want the lawn using up the stored carbs and the weeds suffering for lack of food as the grass has the advantage.

Doug also mentions that he is trying to achieve a moderate green color in Spring (Chlorophyll Index = 250). I'm not - I'm willing to spend more to achieve closer to 300, if I'm not flirting with causing stress/disease. I suspect many members are in that camp, as we're not paying to green-up an entire golf course. Actually, I'm personally testing items that can push the Chlorophyll Index well over 300. That's not ready for prime-time yet - more when the testing is completed...

I'm sticking with my regimen for me and recommending it to others, for a Home Lawn. I personally believe that it is aligned with the Doug Soldat article for Soil-based lawns.

[Green]

I've done it both ways (I'm always performing experiments), and I have found that it makes a significant difference in how long the lawn can go without fertilization the following Spring. That doesn't mean the research and I disagree in my opinion - in my mind it confirms the importance of the exact timing of the last app.

Bingo.

Now, this next part is not a response to what you wrote, but rather, addressing the idea about final Winterizer in general, and the studies that challenge our current way...

I'm going to let slip info about some modifications I've been trying out for a few years as a result of this...

So, a few years back, I saw the studies showing a lot of the N wasn't actually uptaken, but some of it clearly was. So, I got an idea. Instead of using the full 1 lb N rate like in years past, why not cut back slightly on some lawn areas and see how it goes? So a few years ago, I started cutting back on the rate. First I tried 3/4-lb rate on some areas, but still 1 lb on some other areas. The following year, I cut back to 2/3 lb on most areas (but also did 1.25 lb on one area, 1 lb on another, and as low as 0.5 on the low-input area). And this past year (Fall 2018) I cut my final winterizer down to 0.5 lb N rate everywhere, since I didn't see enough differences between the performance of the different areas in previous years. So, we will see how green-up and growth flush goes Spring. Will it be on par with last year and the year before subjectively? We'll see. I would have done a controlled experiment again this year, but there was no time...I nearly missed the window due to snow. But I'll report back with results in the Spring. I'm excited about this, because if I can get the same or nearly the same results with half the amount, that's a good thing as far I'm concerned.

[andy10917]

and the studies that challenge our current way

What studies challenge "our current way"?

[Green]

Some of the work that's the basis of the Soldat lecture (but not the purely golf-relevant or sand based stuff). For example, studies evaluating the uptake of N in late Nov./early Dec. My takeaway from those, when we started discussing them a few years back, was that a.) It was really cool to see the actual N uptake as a function of season, and 2.) (Yes, "2", and not "b") that maybe "the current way" of winterizing handed down to us over time, in which the 1-1.5 lb N rate is used, could probably be challenged. Unlike a lot of other people, I didn't just jump to the conclusion that winterizing wasn't valuable (I had seen the results myself every year since I joined up here). But I did realize maybe I was open to trying to cut the rate down, and see if performance was still good or not in Spring. And that brings me to where I am now...having cut the rate all the way down to 0.5 lb/K and eagerly awaiting the results in the Spring.

A lot of my interest since I joined here has been in winterization. I've asked tons of questions about it almost from day one, learned, tried the various Fall regimens, saw results, kept track, developed intuition and my own ideas, and tweaked and experimented gradually.

So, the short answer is, "current way" pertains specifically to the rate of 1-1.5 (and particularly 1.0) lb/K of N as winterizer. That is what I meant, and I didn't make that clear initially, but should have. Specifically the rate of N used as winterizer.

[BobL]

I think my take is along the same lines, but my question relates to his follow-up comment after banking N from November - a spring application that could have the same effect In that past I've dropped .5lb N via straight Urea alongside pre-emergent in very late March and seem to get pretty much the same results. It would be interesting to see follow-up trials comparing those - especially varying amounts at the two points in time to see what the results may be. Unfortunately, each iteration of a test like this takes at least a year, sometimes two.

The good news is that straight Urea is pretty cheap for home lawn sizes, so I'll stick with a heavy does in early November (typically around 11/10 for me) and then a supplement in Spring if it doesn't jump to life as expected. That's another plus with Urea - grass (at least mine) reacts very quickly to it.

I'll be interested in seeing the outcome of cutting down the late application to .5lb, compared to what you've seen before. That's the nice thing about a community - we can all experiment in different ways and (attempt) to draw some aggregated conclusions.

[Green]

I think my take is along the same lines, but my question relates to his follow-up comment after banking N from November - a spring application that could have the same effect In that past I've dropped .5lb N via straight Urea alongside pre-emergent in very late March and seem to get pretty much the same results.

Pretty similar, maybe. But not exactly the same. The late Fall app does not fertilize early Spring weeds, while the Spring app does. Additionally, the late Fall app does not seem to force earlier wake-up.

[Trike007]

I live in Renton, WA, I applied 8 urea drops up until first frost (Nov 8,2018). But my grass never stopped growing. I never did apply a final app. I measured every week and there was still top growth. How should the Regime be modified for grass that wont go dormant during the fall/winter?

[HoosierLawnGnome]

There are some in the transition zone that treat it more like a pause than a winterization when their turf never goes dormant.

[Tom_SJersey]

Follow up to my post of December 15. Zone 7a. Recap - 2 lbs/1000 Labor Day of Oceangro, a New Jersey version of Milorganite.

Then significant Urea drop early December, front and back yard only. Excluded 2000 sq foot side yard on our corner lot from urea drop. Side yard received the Oceangro application Labor Day, but no December urea.

Follow up: significant early greenup front and back yards starting two weeks ago around mid march.

Front and back yard greenup is far ahead of neighbors. Have cut once at 2 3/4.

Little to no greenup in side yard as of April 1. No growth.

Note: Have been in house for 14 years. Developer put in KGB sod. Poor install significant thatch. Always had trouble getting spring greenup (delayed until mid May) until I started fall application of Oceangro and urea.