National Walnut Day
National Walnut Day on May 17 honors America's most versatile nut — the English walnut that grows in California's Central Valley, the black walnut that grows wild from Missouri to the Atlantic, and the thousand American recipes that feature them. Established in 1949 by the Walnut Marketing Board and signed by President Truman in 1958. California grows 99% of the US walnut crop.
Why it matters
CRACK & CRUNCH!
It’s National Walnut Day. On May 17, America honors the two-lobed, brain-shaped, improbably versatile nut that built California’s Central Valley and Missouri’s hollers — the walnut in every brownie, every banana bread, every Waldorf salad for 150 years.
THE STORY
There are two walnuts in American agriculture. The English (or Persian) walnut, Juglans regia — imported to California by Franciscan missionaries in the 1770s, commercialized in the 1870s, and now grown on ~4,500 California family farms in the Central Valley. And the black walnut, Juglans nigra — native to eastern North America from Missouri to the Atlantic, a prized hardwood for furniture, and a distinctly American culinary tradition all its own.
California built the American walnut industry. The first successful commercial orchard was planted by Joseph Sexton in Goleta (Santa Barbara County) in 1867. The climate — dry summers, mild winters, long growing seasons — proved ideal. By 1900, California was a major US supplier. By 1950, it was the dominant domestic producer. Today, ~99% of US walnuts and ~75% of the global walnut crop come from California. The industry is almost entirely family-owned; Diamond of California (the cooperative) represents ~1,500 farms.
Black walnuts, meanwhile, have never been industrialized. They grow wild across the Eastern US — particularly Missouri, which harvests roughly 20 million pounds per year from wild trees. Hammons Products Company in Stockton, Missouri has been the single major commercial buyer since 1946, processing ~95% of America’s black walnut crop. The hull that surrounds a black walnut is so hard that modern industrial crackers still rely on specialized machinery developed in the 1940s. Black walnuts are richer, more intense, and more expensive than English walnuts — a true American delicacy.
National Walnut Day was established in 1949 by the Walnut Marketing Board (now the California Walnut Commission) to promote California walnut consumption. President Truman signed the first formal proclamation in 1958. The date — May 17 — falls strategically between harvest seasons, when marketing boards want to stoke summer demand. The day honors both American walnuts: the California commercial giant and the wild Midwestern heirloom.
A walnut tree is the one tree in our yard that I wouldn’t trade for a million dollars.
WALNUT VARIETIES WORTH KNOWING
Four walnuts that actually taste different:
California Chandler
The dominant California commercial variety — ~50% of the US crop. Large, light-colored kernels, mild buttery flavor. The walnut in most American grocery-store bags.
Black Walnut
Wild-harvested in Missouri and the Midwest. Much smaller, darker, richer, more intense. Bakers use 1/3 the volume of English walnut for the same flavor impact. A culinary delicacy.
Howard & Hartley
Older California varieties, still grown but less commercially dominant. Smaller kernel, richer flavor than Chandler. Preferred by some chefs for baking.
Chinese & European
China is now the #1 global producer by volume (mostly for domestic consumption). Spanish and French walnuts are common in European markets. Tasting differences are subtle but real.
AMERICAN WALNUT COUNTRY
Six regions shaping American walnut culture:
DID YOU KNOW?!
Walnuts are technically drupes, not nuts.
Botanically, a walnut is a ‘drupe’ (fleshy-fruited seed, like a peach or olive) — the ‘shell’ is actually the seed, and the discarded green hull is the fruit. Americans call it a nut; botanists call it a drupe. The English walnut tree is specifically Juglans regia.
Walnut trees inhibit other plants.
Black walnut trees produce a chemical called juglone in their roots, leaves, and hulls. Juglone is toxic to many plants — tomatoes, blueberries, rhododendrons die near black walnut trees. Allelopathy; a botanical curiosity that frustrates American gardeners.
Walnuts look like brains for a reason — sort of.
The walnut-brain visual similarity is noted in Western folk medicine since ancient Greece (the ‘doctrine of signatures’ — a plant’s shape indicates its medical use). Modern research: walnuts are genuinely good for brain health, high in omega-3 fatty acids. Coincidence or intuition — debatable.
Nashville has a walnut tree from 1797.
The ‘Heritage Walnut Tree’ at The Hermitage (Andrew Jackson’s home) is believed to date from 1797, predating Jackson. A black walnut tree; over 225 years old; still producing. One of the oldest living American walnut trees.
CRACK & READ
The Nut Cookbook
Ted Hsu · 2021
A modern encyclopedia of nut-based cooking — walnuts, pecans, almonds, hazelnuts, pistachios. Clean technique, beautiful photography, recipes from across American regional traditions. The best modern American nut cookbook.
California Walnuts: A History
Margaret Frazier · 2019
A UC Davis-published history of the California walnut industry from the 1870s to today. Agricultural, economic, and social history — the rise of Diamond, the development of modern varieties, family-farm stories. Niche but excellent.
Black Walnut: A Natural and Cultural History
Michael J. Reilly · 2016
A deep regional history of the black walnut in American culture — from Cherokee uses, to pioneer baking traditions, to modern Missouri harvesting. Hardcover, thorough, beautifully researched.
PAIR IT WITH
A rich California Zinfandel or a French Bordeaux. Walnuts and red wine: one of the great American snacking combinations.
Aged Cheddar, Manchego, Roquefort, or aged Gouda. A walnut-cheese board is elegance on a cheese plate.
John Denver — ‘Rocky Mountain High.’ John Fogerty — ‘Have You Ever Seen the Rain?’ American roots music for American roots food.
Wendell Berry’s essays — ‘The Long-Legged House’ or ‘The Unsettling of America.’ American agrarian philosophy over a bowl of walnuts is a genuinely great evening.
Crack It. Share It.
Tag us @celebrationnation with #NationalWalnutDay. California crop or wild black walnut — we want to see your walnut recipes.
How to celebrate
Crack, bake, and snack:
- 🌰 Buy fresh California walnuts. Unshelled if possible — crack your own. The flavor difference from pre-shelled bagged walnuts is significant.
- 🍪 Bake walnut cookies. Oatmeal-walnut-raisin, walnut chocolate chip, classic chocolate-walnut brownies. Universal American baking classics.
- 🥗 Make a walnut salad. Toasted walnuts + goat cheese + pear + arugula + balsamic. Restaurant-quality, 10 minutes.
- 🔨 Try black walnuts. Order a pound from Hammons (Missouri's Hammons Black Walnuts is the major commercial supplier). Far richer flavor than English walnuts.
- 🥧 Bake a walnut pie. Like pecan pie, but walnut. Common in California and Missouri. Maple syrup + walnuts + butter + eggs.
Celebration ideas by audience
For families
Nut-cracking afternoon with a bowl of unshelled walnuts, a nutcracker, and a fireplace. Kids love the physical act; adults get nostalgic.
For kids
Walnut 'boat' crafts — half-shells + toothpicks + paper sails. Classic preschool activity; takes 5 minutes to set up.
For couples
Bake brownies with toasted walnuts for a Friday night at home. Simple, perfect, 45 minutes.
At the office
Bowl of walnuts at the reception desk. A classic afternoon-slump pickup; plus the cracking sound discourages needless stopping.
At school
Great life-science lesson: tree growth, pollination, crop agriculture. California walnut farming is an excellent case study.
In your community
Walnut-themed bake sale at a community event. Brownies, walnut cookies, walnut breads — universally popular.
On your own
A handful of toasted walnuts + a pear + a glass of red wine. One of the great solo-evening snacks.