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On top of Brush Mountain, Pa.

Now that we have resolved the Phosphorus situation, how about Nitrogen? Solomon sets the target for Nitrogen at 200 PPA while Altera say 80 to 100 PPA is where we should be. McKibben does not really address the issue. After you address the target value there is the question of where will it come from. Gardens high in OM may have enough Nitrogen already in their soil waiting to be broken down by the soil biology and so maybe they don't even need any except for early in the spring before the soil really gets warmed up and the soil inhabitants get going. I have to confess that my soil tests have not addressed Nitrogen so I am not sure where I am. I thought my high OM level addressed it but my OM is mostly leaves which are mostly carbon and so when they break down there is not much Nitrogen there. I plan on relying on my soil test from a new lab and tissue analysis. What are your thoughts?

5/2/2019 9:21:40 PM

Oak Grove, Mn

Marv...I think you need to address more....what form is the N in...is it nitrite, nitrate etc. Are you sure you want to open this can of worms....well, i know you do. The last subject was easy....I will bet there are even less people that are sure about N

5/2/2019 9:25:18 PM

Deer Park, WI

Foremost- I encourage growers not to put much, if any value on soil nitrogen tests. This may seem horribly counter intuitive, since you are paying for the metric and the drum has been beat about the importance of soil testing. But as I stated in the phosphorus thread, nitrogen is a whole different animal.

It is important to understand why- electrical charge. Nitrogen, in its most common plant available form (nitrate) carries a negative charge. So does the soil. When you stick two negative ends of a magnet next to each other, what happens? If you answered "they repel" each other, award yourself a gold star. Same thing happens between soil and nitrate. And the direction soil repels nitrogen is down. This is the process called leaching.

Other nutrients hang around because they are positively charged. Calcium, magnesium, potassium are attracted to negatively charged soil. Again, like opposite poles of a magnet. Because these nutrients hang around longer, they can be accurately measured. Since nitrogen is repelled, every time you water, more nitrogen readily flows out of the root zone.

5/3/2019 8:20:36 AM

Deer Park, WI

When you measure soil nitrogen at one point in time, its like counting the number of people in Times Square on New Year's Eve and assuming that number represents the number of people there on every other night. That doesnt work.

In crop production, we manage nitrogen in corn by starting from zero. Quite literally. We know there is nitrogen in the soil, however, we're not using a soil test to build out fertility programs. Instead, as Marv stated above, we use OM as a starting point for nitrogen "credit". Then, based on very well understood facts about crop nitrogen needs, the proper amount of nitrogen is added throughout the season to meet crop needs.

And this is where the topic gets murky for giant pumpkin enthusiasts. There's been no research on "crop needs" for giant pumpkins. Therefore, it is once again time for some logically based assumptions to get us in the ballpark.

I wrote about this extensively shortly after the GPC Big Show this winter, as the topic of nitrogen management was one of significant interest (thank you John Harnica for providing the impetus to put some serious thought into the topic).

I encourage those who are interested search the general forum for my thoughts nitrogen mgmt, as they have not changed since my posts a few short weeks ago.

I've also dedicated a good portion of the soil fertility guide discussing nitrogen. I encourage that as a reference.

5/3/2019 8:34:04 AM

Plymouth, MN

http://www.bigpumpkins.com/MsgBoard/ViewThread.asp?b=3&p=658726

5/3/2019 11:35:14 AM

On top of Brush Mountain, Pa.

Thanks Joe. Always a pleasure to hear your thoughts.

5/3/2019 11:55:17 AM

On top of Brush Mountain, Pa.

But, might it be just as easy and maybe even better to add something like feather meal or fish meal to the garden and let the soil life break it down throughout the season? That way you would have nitrogen available all season long. And the problem with leeching would not be as great.

5/3/2019 12:14:03 PM

Plymouth, MN

I'm going to be doing both. Feather meal incorporated into the soil at amending. During the early season, I'll be using a N-heavy liquid fertilizer while the soil microbes get to work on the complex stuff in the OM and FM.

5/3/2019 12:35:27 PM

Deer Park, WI

A readily available form as well as a delayed-release form are ideal, as Mr. cjb alludes. We know microbes do not start converting OM to plant available nutrients until soil temps hit 50+ degrees. Thus, I believe that those of us in Northern climates (45th parallel and above) will not be getting much OM benefit until deeper into the season. I am planning to provide liquid nitrogen up through early/mid-June, two weeks prior to pumpkin set.

Bear in mind that 5% organic matter or greater provides at least 150lbs/acre of nitrogen. Therefore, if you have 5% OM or higher, additional slow release nitrogen sources like feather meal are unnecessary/redundant if the sole purpose for its addition is nitrogen.

28% UAN liquid nitrogen is the most potent, readily available form that can really boost early season plant growth. Assuming a giant pumpkin requires 150-200lbs/acre and that nearly all of that can be supplied by organic matter post pollination, I am planning on providing 1/3 of that requirement as liquid nitrogen through the first third of the season.

The same nitrogen requirements could be met using other nitrogen sources such as fish emulsion and blood meal, recognizing that their much lower nitrogen concentration would require a much larger application volume to achieve hypothetical nitrogen needs. These calculations are fairly simple to make.

5/3/2019 3:58:07 PM

On top of Brush Mountain, Pa.

Joe, I think some of this depends on the quality of your compost and therefore your OM, correct me if I am wrong. My compost is composed almost totally of leaves which are very low in nitrogen and, in fact, almost totally carbon. Maybe I should be calling my leaf compost leaf mold, not sure. My compost pile hangs around 110 degrees and is probably what some would call fungal compost. Adding this to the garden elevates the OM content of my soil but probably offers very little in the way of nitrogen. I have never had it analyzed. I need to read your publication again.

5/3/2019 5:14:58 PM

On a cliff in the desert

Marv, use the compost I am using. It has a slow release of Nitrogen throughout the season. You know what I am using. I suggested it to you.

5/3/2019 8:09:48 PM

Morgantown, WV

I was recently shamed for not testing Nitrogen... it is nice to know others treat it as I do, a leachable element that is to be applied if needed, otherwise obtained from the soil OM.

Yes, you can try to manage it, but it is in fact one of the more complex processes of soil health as Joe mentioned. More importantly than the type of nitrogen in your bag, is the type of soil that you have, and the PH and OM that you have... then and only then do you understand what type of N to have in that sack and when to toss it all over your patch.

If you want to have a comprehensive understanding of nitrogen in your soil, I suggest petitioning a lab to get a bulk rate on weekly tests, otherwise you won't see how fast it fluctuates over a season of rainy weather to hot and heavy pull on the soil then back to cold and wet.

5/3/2019 9:23:37 PM

On top of Brush Mountain, Pa.

Wile, please remind me about your compost. Dustin, weekly testing is more than I can handle. If I had paid more attention to my nitrogen I might have had bigger onions and bigger tomatoes as well.

5/3/2019 10:11:41 PM

On a cliff in the desert

Read my email that I sent you. It has lots of information for you. I hope it didn't end up in the trash folder.

5/3/2019 11:38:06 PM

Grittyville, WA

There is that corn gluten weed suppressor... Seems to increase dampening disease with protein/carbohydrate based nitrogen... and thats how it kills weeds?? And those weeds that do manage to germinate then grow twice as big? Ammonium can enhance the affect if roundup. Funny that both forms of nitrogen can be used against plants in certain circumstances.

5/4/2019 3:59:33 AM

Bethlehem CT

When a grower talks about looking at his plants and gauging their need for fertilizer most likely he is gauging whether or not they need a shot of Nitrogen. Any grower who has more than a few seasons under his belt can recognize the symptoms of excessive Nitrogen.
Which are excessively green leaves and curling,turgid,and,splitting vine tips. ) . That same grower can also identify when his plants are deficient in N. (Leaves that could be greener, growth that could be more vigorous) . The problem lies in figuring out what is the most ideal level to have the Nitrogen at, when the human mind and eye can't observe the need for it.
Glenoma from what I have heard and seen, I wouldn't waste my money on corn gluten meal as a herbicide, perhaps it's value would be more useful as a fertilizer.

5/4/2019 8:37:17 AM

Grittyville, WA

Im sure it has a narrow range of usefulness and economics... At best.

5/4/2019 11:25:30 AM

Grittyville, WA

But, loosely on the topic of nitrogen, it seems to me that some nitrogen sources do seem to promote bad performance at vulnerable stages of growth. Other fertilizers like magnesium may not have this affect.

Nitrogen is interesting and as its been stated here the two forms, positive ammonium and negative nitrate, are so different. It seems frustrating when a simple "N" turns out to be more complicated but if you just resign yourself to spending twice the effort when it comes to nitrogen, then its not a big deal. I recommend to spend the time and figure it out as though it was equal to two important minerals, not just one. & This is coming from someone who loves to cut corners. My own plants may still be short on nitrate, but they may have so much ammonium, I am risking the extra bloated growth & associated problems. I for one, am interested in discussing nitrogen further.

5/4/2019 12:01:01 PM

Grittyville, WA

I know the big growers use plenty of nitrogen overall. Some advise cutting back near bloom time. This is probably good advice if you are using too much. But if youre not using too much to begin rith, then cutting back may not be necessary or beneficial. And that begs the question... Why use too much in the first place? The goal is a bloated overgrown pumpkin not overgrown leaves or snapping vines. So would it actually make more sense to bump nitrogen up after pollination? But I am probably off track here... Potassium and calcium makes good fruit. Nitrogen mostly makes problems as far as I know.

5/4/2019 12:11:47 PM

Grittyville, WA

*with not rith

5/4/2019 12:13:15 PM

On top of Brush Mountain, Pa.

Okay. After all these very informative posts, here is what I think. Correct me if I am wrong. Chime in. Speak up. First of all consider nitrogen to be something that you are going to need to add each season as it is pretty much disposable and gone by starting time in the spring or at the end of the growing season. The amount of nitrogen needed for an entire growing season is controversial. Some say 100 PPA and others say 200 PPA. I am going with 200PPA. Consider compost to be organic matter with no appreciative nutrient value except to soil life. Chemical nutrient people as well as organic need to be sure there is some immediately available nitrogen in the spring before the soil warms up so chemical people go with ammonium nitrate or urea or liquid nitrogen. For the rest of the year chemical people divide the 200 PPA into three feeding sessions with 1/3 going in each time they add their nitrogen. They can do the calculations. Those that are chemical and fertigate put the 200 PPA into their watering system and dribble it in all season. Organic guys add something for early spring nitrogen, maybe alfalfa meal or bat guano. For the basic 200 PPA they add feather meal, fish meal or seed meal or a combination of these either late in the fall or early in the spring. Give me your best shot! Grow Big !

5/4/2019 1:41:41 PM

Deer Park, WI

Well said Marv.

5/4/2019 3:51:12 PM

Grittyville, WA

Love the topic. Correct me if I am wrong:
Organics seems to add ammonium. Even my compisted green grass is not testing as having nitrate. I know it does but... The microbes or funguses seem to eat all the nitrate. You say they convert ammonium to nitrate? A lot of them eat nitrate even when the compost has a lot of greens the nitrate may end up being zero. Its kind of extreme. Well maybe some do eventually make nitrate... maybe thats why azos helps?

5/4/2019 5:41:58 PM

Deer Park, WI

A couple comments on “reading your plants” for nutrient issues. It is true that nitrogen deficiency and excess result in fairly recognizable plant habits. When these visual cues manifest, growers can react. Therein lies the fault, however. Being reactive to nutrient excess/deficiency might save the plants from disaster, but by the time plants show signs, pounds of weight may have been given up. We do need to be responsive to plant needs, but nutrient management extremes should be avoided by optimal planning.

5/5/2019 7:26:30 AM

Deer Park, WI

The second comment on reading plants concerns “reductionism”, a process whereby we as humans try to reduce a potentially complex issue down to its simplest explanation, potentially overlooking other very important facts that underly the issue. Small leaves, short internodes, and light green coloration generally describes what nutrient deficiency? If you said nitrogen, enjoy a gold star. As someone who’s battled pythium root rot for a decade, I know it’s also the trademark stamp of this devastating disease. Both observations are correct, as root pathogens effectively destroy a plants ability to take up nutrient, initially giving impression of nutrient deficiency. However, it’s easy to see that applying nitrogen to a diseased plant won’t restore its health. I respect those who claim to have an eye for reading their plants, but I also remind myself that there are 17 different nutrients a plant needs for survival, many with similar symptoms of deficiency, a handful of fungal, bacterial, and viral diseases that initially mimic nutrient deficiency, and other types of environmental stressors that all contribute to plant habit/appearance. I stress caution when reducing an observation to a straight forward cause.

5/5/2019 7:43:04 AM

On top of Brush Mountain, Pa.

Joe, is this some of what makes tissue analysis a valuable tool? Should serious growers be doing tissue tests on their plants each year and, if so, when. I have heard that for tomatoes the right time to get this test is when the blossoms begin to form. Same for pumpkins? Most of those doing these tests seem to be doing them once a year. When would the right time be? I long ago gave up on reading my plants. At one time I was comparing my leaf color with paint chips trying to see the changes. I just wasn't good enough.

5/5/2019 8:58:38 AM

Deer Park, WI

Tissue testing is a complex animal.

For it to be of value, the first step is to ensure the numbers you get on a test report are not being influenced by a root pathogen. As with "reading plants", what appears as a deficiency might be due to disease rather than standalone nutrient deficiency. In which case, pouring more nutrient will not fix the problem and your ~$100 tissue test was money down the drain.

So, those who venture to use TT should be reasonably certain root disease and other systemic pathogens (bacterial wilt, etc) are not affecting the plant.

I also struggle to find the value in a single tissue test, regardless of pathogen pressure. Here I invite others with more experience to offer their insights. One test performed somewhere in the middle of the season gives you a little bit of information on the nutrient status of your plant, to which you can make some adjustments. The challenge is that if a nutrient shows up low on a tissue test, that doesnt always mean its low in the soil. Thus, TT's should always be run in parallel with soil tests for the most accurate assessment.

5/9/2019 8:15:13 AM

Deer Park, WI

And here's where it becomes more complex. For TT to be of most value, multiple tests should be run in succession. Adjustments made after the first test can be monitored for impact/effectiveness. This level of analysis is likely cost prohibitive for most growers. There is also the question of impact. For extreme deficiencies, adjustments may prove effective at the scale. But for values just outside of published ranges, there may not be noticeable benefit in the performance of plant/pumpkin. Extreme deficiencies should be picked up in the soil test.

In sum, this reads as somewhat negative perspective on tissue testing. But please dont let that serve as gospel. I am certain there are others for whom this tool provides useful insight and I'd be curious to hear their thoughts.

5/9/2019 8:24:00 AM