Thompson Seedless grapes haven’t gone extinct, but they’ve largely vanished from grocery store produce sections over the past two decades. The variety that once dominated American fruit aisles has been steadily replaced by newer, patented seedless grapes bred for bigger berries, crunchier texture, and longer shelf life. Thompson Seedless is still widely grown, but most of that crop now goes to making raisins.
Why They Disappeared From Grocery Stores
For most of the 20th century, Thompson Seedless was the default seedless grape in the United States. It was everywhere. But starting in the 1990s and accelerating through the 2000s, grocery chains began swapping them out for newer varieties with traits that made more commercial sense: thicker skin that survived shipping without browning, larger berries that looked better on shelves, and flavors engineered to be sweeter or more distinctive.
Thompson Seedless grapes are particularly sensitive to warm temperatures during handling and transport. Even moderate heat exposure causes the berries and stems to brown, giving them a wilted, unappealing look by the time they reach consumers. Newer varieties were bred specifically to resist this kind of deterioration, giving retailers a longer window to sell them before they looked past their prime.
Size standards also played a role. The berries on Thompson Seedless vines are naturally small compared to modern table grapes. Retailers and export markets increasingly demanded a minimum berry size, and Thompson Seedless couldn’t consistently meet those thresholds without extra vineyard labor like thinning and growth treatments. Newer varieties produce large berries more reliably, which made them cheaper and easier to bring to market at the quality consumers expected.
The Rise of Patented Varieties
The grape industry underwent a fundamental shift in how new varieties reach growers. Historically, when the USDA developed a new grape variety, it was released without a patent. Any grower, domestic or foreign, could obtain the plant material, grow it, and sell the fruit. That open system meant American growers had no competitive advantage from new varieties, since foreign producers could plant the same grapes and undercut them on price.
The industry pushed to change this through exclusive licensing agreements. Under the newer model, a variety can be patented and sublicensed to selected nurseries, with restrictions on where the fruit can be sold and during which seasons. As one industry leader put it, this gave growers “an amazing opportunity to control, to some degree, its own destiny with future variety releases.” Companies like International Fruit Genetics and Sun World began developing proprietary grapes with catchy brand names and distinctive flavors, from Cotton Candy to Sweet Celebration. These branded grapes command higher prices and generate licensing revenue, creating financial incentives for everyone in the supply chain to move away from unpatented, commodity varieties like Thompson Seedless.
The result is that what you see in the grocery store today is a rotating lineup of patented grapes, often marketed under trademarked names rather than variety names. Thompson Seedless, with no patent protection and no branding, simply couldn’t compete for shelf space.
Where Thompson Seedless Went
The variety hasn’t disappeared from farms. At its peak in California, Thompson Seedless covered roughly 263,000 acres, making up about 38% of the state’s total grape acreage. Around 150,000 of those acres were devoted to raisin production, with the remainder split between table grapes and wine. That balance has shifted further toward raisins over time. Thompson Seedless remains the primary raisin grape in California, and it’s still the world’s most widely planted light-skinned grape variety overall.
Originally known as Sultanina, the variety traces back to Turkey and has been cultivated for centuries. It was popularized in California by a viticulturist named William Thompson in the 1870s, which is how it picked up its American name. Its thin skin and high sugar content make it ideal for drying into raisins, a use where the very traits that hurt it as a table grape (small berries, delicate skin) are actually advantages.
How Modern Grapes Compare in Flavor
One thing people remember about Thompson Seedless is the flavor: light, sweet, and straightforward. In terms of sugar content, Thompson Seedless grapes are typically harvested at around 16 Brix (a measure of sugar concentration in fruit). That’s slightly lower than some modern varieties. Crimson Seedless and Red Globe, for example, are harvested at 17 Brix, and under ideal conditions grapes can reach 20 to 21.5 Brix. The newer patented varieties were often bred to hit higher sugar levels while also adding more complex flavor notes, which is how you end up with grapes that taste like candy or muscat.
That said, many people feel the newer varieties lack the clean, simple grape flavor they grew up with. The nostalgia is real, and it’s one reason this question gets asked so often. Thompson Seedless had a balanced, mild sweetness that didn’t try to taste like anything other than a grape.
Thompson Seedless as a Genetic Ancestor
Even though Thompson Seedless has faded from produce aisles, its genetics live on in most of the seedless grapes you eat today. The seedless trait in grapes was originally derived from ancient cultivars, primarily Thompson Seedless and a variety called Black Monukka. Most seedless grapes bred for the American market descend from crosses involving one of these two parents.
Cornell University’s grape breeding program, one of the most important in the country, used Thompson Seedless as a foundation. Himrod, their most successful table grape release from 1952, came from a cross between Ontario and Thompson Seedless. Interlaken Seedless and Lakemont, two other well-known eastern varieties, came from that same cross. So while the original Thompson Seedless may be hard to find at your local store, its DNA is in nearly every seedless grape on the shelf.