Snow—especially a late snow in the spring—has long been called the “poor man’s manure” or “poor man’s fertilizer.” The snow contains nitrogen that helps plant growth.
   
“The snow is emphatically and truly called the poor man’s manure” was cited in print in 1810.
 
“If snow is the poor man’s fertilizer, there can be no grumbling this year for lack of that precious material” was cited in print in American newspapers in March 1869.
 
 
Old Fulton NY Post Cards
4 March 1869, Troy (NY) Daily Whig, pg. 4, col. 4:
SNOW.—If snow is the poor man’s fertilizer, there can be no grumbling this year for lack of that precious material.
   
Old Fulton NY Post Cards
28 January 1871, The Spirit of the Times (New York, NY), “A Deep Snow,” pg. 377, col. 1:
But the snow does much good to the arable and pasture land, and being thus the poor man’s fertilizer, it compensates upon the whole for all the suffering and labor it entails.
     
Old Fulton NY Post Cards
6 May 1875, The Deaf-Mutes’ Journal (Mexico, NY), pg. 2, col. 5:
There is a saying that these snows are tlio poor man’s fertilizer.
 
3 February 1886, North Vernon (IN) Plain Dealer, pg. 8, col. 3:
The Poor Man’s Fertilizer.
Prof. John Collett, in the interest of the poor man, is pining for a snow. He says that snow is a superior fertilizer. It contains a considerable amount of ammonia, and is the surest and best manure that a poor man can have.
 
25 February 1887, Juneau County Argus (New Lisbon, WI), “Proverbs About Snow” from the Boston Journal, pg. 7, col. 1:
Snow is a poor man’s fertilizer, and good crops will follow a winter of heavy snowfall.
 
16 February 1902, Winston-Salem (NC) Journal, “What Caused the Big Snow,” pg. 1, col. 4:
Around the warehouses it was easy to see that the farmers are taking a grain of consolation this morning over the beautiful snow. They know full well it is the only salvation of the wheat. While many acros are of the “staff of life” are perhaps too nearly starved or frozen out, yet there are some to which this fairy shower of the “poor man’s fertilizer” will be a boon.
   
Google Books
Piano Trade Magazine
1913
Pg. 182:
The Poor Man’s Fertilizer.
Earl Jackson, the Middle Western traveler of the Cable Co., looked out of the window and watched March come in like a lion. “I hope it snows hard and keeps it up. Snow is the poor man’s fertilizer. Look at the crops we had last year and the resulting piano business. Business has started off this year with confidence, and if the crops are good this season this year will be a record breaker.”
 
Farmers’ Alamanac
The Poor Man’s Fertilizer
by Peter Geiger | Tuesday, January 29th, 2008 | From: Blog
When I was small, I heard that it was good when it snowed because it was called a “poor man’s fertilizer”. The person that told me was an old farmer, so I never questioned the saying. Is there truth behind the saying?
 
Aside from water, nitrogen is the only element that snow puts back into the Earth. However, lightning and rain actually emit a greater proportion of nitrogen than snow. What probably makes snow good for the soil is that it feeds nitrogen into the soil at a slower and more even rate (through melting) than a thunderstorm, which delivers precipitation at a more rapid rate.
     
Green Mountain Garlic
VERMONT SNOW: WHY IS IT CALLED “POOR MAN’S FERTILIZER”?
Posted on February 17, 2011 by garlic
The snow this year in Central Vermont is magnificent, our garlic farm is covered with a glorious blanket of it prompting many friends to ask “How is the garlic doing under this blanket?”
 
It’s great! The blanket contains nitrogen. As snow and rain fall through the atmosphere, they gather nitrogen. But because the ground is frozen now, much of the nutrients contained in this snow will run off. Spring snow, on the other hand falls on ground that is not frozen and leaches nutrients (including nitrogen) and moisture into the soil, thus “Poor Man’s Fertilizer”.
 
The Daily Gazette (Schenectady, NY)
Poor man’s fertilizer
By Henry Lind
Tuesday, April 22, 2014
Last week’s snow was a surprise to many but welcomed by those of us who are tilling the soil in gardens or farms. Late season snow has been called “poor man’s fertilizer” for generations but we may not realize that it really deserves the name, with perhaps the gender specific reference as an exception. In fact, any moisture falling from the sky contains nitrogen, the single most important element for plant growth. When it arrives in the form of snow, the added benefit is what we can describe as slow release fertilizer. Unlike a rainstorm, the nitrogen in the snow stays put on the soil as the snow melts, and does not run off quickly.