Locally In Season: Sweet Onions

Ready for your Cliffy Claven fact of the day? Sweet Onions actually have less natural sugar in them than regular brown onions. What! Sweet onions are 8% sugar compared to the 12%, than what consumers call brown onions, but are usually grown, traded and sold as storage onions.

There are 4 factors in making an onion sweet: variety, soil, water content and growing temperature. Most sweet onions, wherever they are grown come from a Grano/Granex variety, for Vidalia’s there are 17 approved strains that can be grown, the sweet onion exception is Walla-Walla (more on that in a moment). Climate, micro-climate and soil conditions are always a factor in growing, the French concept of terrior does the best job of explaining this phenomena: The soils in  sweet onions fields are low in sulfur compounds, the low sulfur characteristic gives the onion its namesake sweetness. What little sulfur can be found is watered down - when comparing to storage onions, you’ll often hear people drop the adjective ‘juicy’ to describe the profile of a sweet onion. It is true and accurate; also worth noting, the strongest onions have the least water stored in their root.

Another paradox of sweet onions is they are associated with warm weather, Vidalia, Maui, Texas’ Sunbrero or the high desert fields of the Walla-Walla, yet cooler weather produces milder flavors. The answer to this paradox is most sweet onion seeds are sewn in the fall, slowly growing in the cool months netting a milder flavor.

Closer to home, Pacific Northwesterners have Walla-Walla onions. Geographically, Walla-Wallas have many of the attributes needed for sweet onions - located on the dry side of the Cascades in what would normally be a very dry climate, Walla-Walla onions are grown in region that has access to irrigation from river flow and benefits from ample snow pack. Unlike other sweet onions, our local variation comes from a different strain of seed than the Granex. In the late 1800s, a French soldier, Peter Pieri, brought a strain of onions from Corsica and introduced the varietal to the veg loving Italian farmers in the region - The birth of multi-culturalism in the Columbia basin or progenitor of fusion cooking? Selective plantings and adaptation to local growing conditions have produced our own branded sweet onion, whose season, like our summers, starts and stays a little late.

The fact of the matter, a Walla-Walla or Vidalia Onion could be grown in Iowa if not for the treat of a lawsuit. Vidalia’s were one of the first branded agricultural products in the US, eventually receiving State designation and Federal recognition in the 80s. Vidalia’s have transformed from the byproduct of a warm climate, first-to-market, spring crop into a premium agricultural product available 9 months a year. This was accomplished by use of aggressive marketing and Controlled Atmosphere (CA) technology, the same kind of low oxygen environment used to prolong the life of apples and pears.

So while Vidalia’s are a nice but extending the brand and season have diluted the quality.  Walla-Walla’s are better (seasonal/local), but I am not brand loyal. Give me the sweet onion that came out of the ground yesterday, a stick of butter and some chèvre and two hours and we can all enjoy a sweet onion tart.