The Dirt Below Our Feet

Every discussion of a wine region’s quality begins with the soil.  Going back to ancient Roman times, around ad 50, Lucius Columella advised, in his treatise on viticulture, De Re Rustica (“On Agriculture”), “Before you plant a piece of ground with vines, you should examine what sort of flavor it has; for it will give the wine a similar taste. The flavor can be ascertained…if you soak the earth in water and taste the water when the earth has hone to the bottom.  Sandy soil under which there is sweet moisture is the most suitable for vines…any soil which is split during the summer is useless for vines and trees.”

The “useless” soil that splits is clay, a colloidal suspension of particles similar to Jell-O. Clay retains too much moisture when it rains, making the tender roots of wine grapevines rot; it withholds nutrients from the vine when the weather is dry.

There is little clay on the East End of Long Island, except in specific and easily identified veins. We have remarkably uniform sandy soils here that vary in available topsoil (loamy organic matter), but all contain the same fundamental yet complex mixture of minerals.  These soils are ranked by the U.S. Soils Conservation Service as “1-1,” the most auspicious rating for agriculture. Any single handful of Long Island soil will show the reflective glint of mica; the dull gray of granite; the mellow pink, salmon and white of quartz; the red and ochre of sandstone; and black bits of volcanic matter. To describe them simply as “sandy loam” fails to acknowledge the profound effect that having this mixture of minerals must have on the vibrancy and dynamic quality of Long Island’s wines.

Long Island’s soils were formed long after Earth was born as a ball of fire, cooling slowly, so that over its still-burning core, 400 million years ago, a sheath of solid metamorphic rock formed.  That rock is the foundation lying 760 feet under Long Island.  From that time on, important geologic events would tear apart existing formations—from volcanic activity that split landmasses into our now familiar continents, to the glaciers that have stopped at nearly the same point to carve out Long Island twice over the past 150,000 years.

Two ridges of terminal moraine, the endpoint of two glaciers, joined at the west end of Long Island, but split at the island’s end, forming the North and South Forks. Imagine a wall of ice, 1,000 feet high, looming over the edge of what is now Connecticut, then melting and receding. The ice embedded and ground up chunks of rock from every part of the continent as it traveled south from the North Pole, depositing the residue as Long Island’s soil, the terminal moraine.

The importance of these geologic shifts for modern grape growers is that the unconsolidated deposits of glacial clay, silt, sand and gravel they brought to Long Island, at the outer reaches of terminal moraine, have an unusual ability to allow vine roots to penetrate deeply while making moisture and nutrients available without holding in excessive water or depriving them of oxygen.  Because the North and South Forks were formed at different times, their soils are slightly different: the South Fork’s soil is heavier, holding more moisture. This is why, historically, access to irrigation has been more important to farmers (especially potato growers—potatoes need plenty of water) on the North Fork than in the Hamptons.

But grapevines hate wet feet—that is, the plant’s roots don’t do well when they sit in soggy soils for extended periods. Instead, in some ways, they thrive in drier soils. When grapes are slightly stressed by lack of water, they will put their energy into ripening fruit instead of making more leaves. This is why vines are so often planted on mountains or in poor soils where few other crops thrive, and why low-lying areas typically produce undistinguished plonk. For some wines, like those of Champagne, chalky limestone soils provide the stress that promotes quality. Long Island’s soils are more similar to the gravelly sand of the Médoc, where many famed grands crus (Lafite Rothschild, Margaux, Latour, Mouton Rothschild and Haut-Brion) are grown.

Most grape growers today, on both Forks, have drip irrigation so that they can more easily establish young vines and avoid excess stress in times of severe drought. In the 37 years since the first wine grapes were planted here, increasing attention has been paid to which varieties prefer relatively sandy or loamy sites.

Despite the general uniformity of our soils, there are identifiable differences, especially on farms that have been mechanically tilled for decades. The heavy tractors and combines used to farm potatoes and grain crops since the 1950s have caused the finest clay to drift to the depth of the plow blade, leaving a “hard pan” of compacted soil a few feet below the surface, impeding the vines’ ability to establish the kind of deep root system needed to yield complex flavors in wine. Over the years, Long Island’s vintners have done well to look to their soil when thinking about the health of their vines.

At Croteaux Vineyards in Southold, owners Paula and Michael Croteau had their land extensively analyzed and mapped before planting it in vines. When they methodically excavated deep trenches in a grid over their land, they were able to see how extensively the roots of existing plants delved through layers of topsoil and sand. By choosing different rootstocks for lighter or heavier soils (e.g, “riparia” rootstock on loam; “3309” on sand), they were able to equalize the vigor of all their vines.

Based on increasing knowledge of soil and varietal affinities, vintners now prepare their land to eradicate the hard pan, either “ripping” the soil mechanically, or planting deep-rooting grasses a year or two before planting vines, then plowing them under.  Because grapevines are perennial plants, they need less tillage than annual crops. Although we used to “clean cultivate” to control weeds in the early days of grape growing on Long Island, by the ’90s almost all vineyards had planted a permanent grass cover that reduces the need to till and helps control vigor. Some growers have gone further, adopting sustainable, organic or biodynamic practices that promote the growth of biodiverse vegetation in the alleyways.  This is a complex mixture of plants that can fix nitrogen, control humidity, and attract beneficial insects while increasing the friability of the soil.

At Macari Vineyards, Joe Macari Jr. has spent the past 10 years developing and refining a compost that has succeeded in naturally improving the health of his soils, and his vines, reversing a legacy of land deadened by prior decades of farming undiversified crops, using chemical fertilizers and herbicides and tillage with heavy equipment. Macari’s compost includes fish, in a return to a practice of some 19th-century North Fork farmers who seine fished for menhaden that they composted for fertilizer.

Not all of our region’s traditional soil-tending activities—calibrated for voracious annual crops like cauliflower and corn—make sense for today’s vintners. Historically, although most farmers kept livestock, their manure was often not enough to revitalize Long Island’s soils for the vegetable crops that were grown here. In an 1863 letter home to Long Island from Virginia, where he was fighting for the Union during the

Civil War, Long Islander Henry Prince wrote his father, “If you only had manure you could do well, tho’ that is the grand difficulty with L.I.          farming. It takes too much for manure. If I had no relatives there, I would not stay there long after the war.”

Maybe if he had been growing grapes, which need far less fertilizer than vegetables, he would have been more optimistic. Of course, had he returned from the Civil War in 1864 and planted wine grapes, they would have succumbed to other scourges like mildew and phylloxera, scourges that were not treatable for many decades. Considering that every era brings different challenges, today’s vintners can agree with Henry Prince’s last advice to “keep up good spirits, times might be worse. We have many blessings more than we return thanks for…we make ourselves miserable when we ought to be joyful.”

Louisa Thomas Hargrave, after 27 years as Long Island’s pioneer vintner, is now with Daniel Gale Sotheby’s (Cutchogue), consults for WineWise and writes from her home in Jamesport.