Whereas different varieties of peaches and nectarines can be so similar in appearance that even the farmer who raised them can’t tell one type from another, there is no such difficulty with plums. Unlike their conformist stone fruit cousins, which come in standard uniforms of gold and red, plums stand out by flaunting their individuality like so many fashion models turned loose in a corporate headquarters. There are yellow plums, green plums, red plums, scarlet plums, purple plums and even plums that are almost black. This abundance has not escaped the notice of fruit marketers. Every summer grocery store produce managers across the country go a little crazy for a couple of weeks in what has come to be called in the trade “Plum-a-Rama”—piling up as many different colors of plums as they can find. And, in fact, it has been shown that offering a variety of colors results in far more sales than if the stores had just one.
Unfortunately, that variety is often scarcely more than skin-deep. Bite into most commercial plums today, and you’ll find only slight variation on the theme of sweet and tart. The surprise that comes with the unexpected flavor notes found in great plum varieties—the wild herbaceousness of an Elephant Heart, the golden honeyed tang of a Wickson, the almost unbearable sweetness of a greengage—is increasingly elusive. For the most part, the market is dominated by large black plums that, in the carefully couched language of fruit catalogs, “can be good when fully ripe.” That may be changing, though.
Plums are wildly promiscuous fruits, cross-pollinating and sporting with abandon. Plant breeders have taken advantage of this tendency by crossing varieties back and forth to try to develop improved varieties. The plum assortment in your neighborhood grocery store is likely to be a kind of living museum of the modern history of fruit breeding, with varieties developed by the great Luther Burbank at the turn of the twentieth century piled right next to varieties that were introduced only a couple years ago.
In his long career, Burbank developed more than eight hundred varieties of vegetables, fruits and flowers, ranging from the baking potato and the freestone peach to the Shasta daisy, but he was especially interested in plums, creating more than one hundred varieties. Probably his greatest was the Santa Rosa, named after the Sonoma County town in which he did most of his work.
The Santa Rosa is a dark red plum with amber flesh and a rich, winey flavor. Unfortunately, because it rarely grows to a very great size, it has fallen from favor. In the 1960s Santa Rosas dominated the plum harvest, accounting for more than a third of the total production. As recently as the mid-1990s, they were still as much as 10 percent of the harvest. Today they make up less than 1 percent. Still, it is a noisy minority—Santa Rosa is one of the few plum varieties sold by name in grocery stores.
Right next to Burbank’s plums, you’ll find cutting-edge crosses developed by Floyd Zaiger, Burbank’s modern-day counterpart. Zaiger has revolutionized the plum business by crossing plums and apricots to come up with the Pluot (he owns the trademark on the name). Burbank had tried to cross a plum and an apricot, but his plumcot varieties were all either poor quality or light bearing. Plums account for the majority of the lineage in these crosses. Zaiger also has trademarked the Aprium, which refers to similar crosses where apricot characteristics dominate.
The first commercial Pluot was introduced in 1989, and those plum-apricot crosses now account for as much as a quarter of the plum harvest. The best varieties are Dapple Dandy (pale maroon skin and creamy red and white flesh, sometimes sold as Dinosaur Egg), Flavor King (reddish purple skin and red flesh) and Flavor Supreme (greenish maroon skin and red flesh).
WHERE THEY’RE GROWN: For all intents and purposes, California grows all of the country’s plums, almost entirely in the same part of the Central Valley around Fresno where peaches and nectarines are grown.
HOW TO CHOOSE: Plums should be deeply colored, shiny and firm, but not hard (of course, neither should they be spongy). Don’t worry if there is what looks like a white powder covering the surface; this is a natural “bloom.”
HOW TO STORE: Like other stone fruits, unripe plums will improve if left at room temperature for a couple of days. And also like other stone fruits, if unripe plums are refrigerated, the quality will suffer. Once they’re ripe, refrigerate them, tightly wrapped.
HOW TO PREPARE: Split a plum along the cleft that runs from stem to blossom end. The pit should pop right out.
ONE SIMPLE DISH: Simmer 1 cup red wine, 1/3 cup sugar and a sachet containing 4 whole cloves, 1 teaspoon black peppercorns and 1 cinnamon stick. When the mixture is clear and fragrant, add 1 pound pitted and quartered plums. Simmer until they soften a little, then refrigerate until chilled. Remove the sachet and serve over vanilla ice cream.