Plums take me way back, to the summers my family spent at the Jersey shore in the 1970s and '80s. My mother would pile us three kids and our dog Mumford into her orange Pinto hatchback, and we'd put-put across the Benjamin Franklin Bridge and onto a long, seemingly endless road (but not a highway -- my mother doesn't do highways) dotted with fruit stands, where she'd load up on plums, her favorite (and therefore ours). Plums were something to be eaten at the beach, which typically resulted in a sandy garnish, but after that first juicy bite into the inky skin that gave away to sweet rose-colored morsels, no one seemed to complain. Our beach snacks, it seems, were always warm in that sack lunch kind of way, a far cry from the icebox plums described in William Carlos Williams' 1962 poem, This is Just to Say.
I was well into my thirties until I experienced something other than the common purplish hybrids of my youth. I would come to love plums in shades of yellow, pale green and red-orange, and marvel at the dreamy purply-gray Italian prune plum shaped like an itty-bitty football. As with so many other summer produce goodies, plums are a here-and-now treat that require our immediate attention; summer isn't just the best time to eat plums, it's the only time.
Although not as ancient as the figs, dates and olives of Mesopotamia, plums are among the first domesticated fruits in central Asia and Europe. Plum stones believed to be from wild species have been found at Neolithic (4,000-2500 BCE) sites in the Ukraine among the Trypilian culture, as well as at sites in Germany, Switzerland, Austria and Cyprus. Plum remnants were also found at Bronze Age sites in Switzerland, Hungary and England. Stones found at an archeological site in Dorset suggest that plums were growing in England well before the Roman conquest.
Plums are among the edible plants mentioned in the I Ching, the earliest surviving Chinese text that dates to the 5th century BCE.
By the 1st century BCE, the Romans were enjoying plums from Damascus, Syria thanks to Pompey the Great, a military leader during the fall of the Roman republic. By the Middle Ages, those plums would become known as damsons, derived from the Late Middle English word damascene, which means "of or relating to the city of Damascus."
Plums were among the fruits grown on Charlemagne's ninth century royal estate in northeastern France.
On the other side of the pond, early colonial settlers observed native Americans enjoying wild plums that grew along the coast of Cape Cod. Now known as a beach plum, this plum is enjoying some attention as a heritage food (see Cultivation section for more).
Massachusetts was also ground zero for Luther Burbank, a 19th century botanist who trekked across the country in the 1870s to Santa Rosa, California, where he developed more than 100 varieties of plums, among them the Santa Rosa, a Japanese cross breed. His crossbreeding efforts set the stage for the American fresh plum industry, which has made Asian varieties and Asian crossbreeds its claim to fame.
But for prunes -- now known as dried plums -- the credit goes to Louis and Pierre Pelliers, two brothers who came from France in the mid-1800s to plant Agen prune plums which they grafted with a wild American plum, resulting in the California prune. By the turn of the century, there were 85 dried plum packing plants in California, which would become (and has remained) the world leader in dried plum production. By 1932, California rolled out commercially-produced prune juice.
- The plum blossom is revered in China and has been depicted in paintings and poetry for millennia. It is seen as a symbol of endurance and renewal.
- In the Middle Ages, the word "plum" was used to refer to various kinds of dried fruit, such as raisins or currants. In Little Jack Horner, the 15th century English rhyme, Jack pulls out a plum with his thumb from his Christmas pie, but it was likely a raisin. (In recent years, there has been speculation that the rhyme was about real estate swindling during the reign of Henry VIII.)
- Prunes are mentioned in The Winter's Tale, the 1623 play by William Shakespeare. (Act IV, scene iii)
A race or two of ginger, but that I may beg; four pounds of prunes, and as many of raisins o' the sun
- At his Mount Vernon estate, George Washington built an orchard in 1786 that included several varieties of plum trees.
- Green-thumbed president Thomas Jefferson experimented extensively with plum trees; he planted 27 varieties in his south orchard at Monticello in the late 18th century. However, the varieties he brought from Europe were unable to adapt to the humidity and heat of Virginia, and so by 1811, he had just two remaining plum trees in the orchard.
- Virginia House-wife, the 1836 cookbook by Mary Randolph includes a recipe for "plum pudding" (page 122 ) which calls for "one and half pounds of raisins" but no plums. Yet for her recipe "Magnum Bonum Plums in Brandy," she calls for green gage plums. The large amber, and the blue plums, are also excellent," she writes. (P. 161)
- Since the late 1990s, a barrier island on the Jersey Shore, has hosted an annual beach plum festival every September. Located near Seaside Heights, Island Beach State Park is among a small number of remaining natural habitats of wild North American "beach plums." (This year, the festival will take place September 7. Watch for details here.)
- In 2011, the "beach plum" was recognized as the official fruit of Cape May County, New Jersey.
- In 2000, the Food and Drug Administration (FDA) granted permission to the California Prune Board to permanently swap out the use of the word "prune" for "dried plum" on all its packaging. Stagnant sales resulting from a long-held public perception that prune equals laxative, the industry sought a rebranding and is now known as The California Dried Plum Board.
Botanically speaking, the plum is part of the Prunus genus, which includes various stone fruits -- apricot, cherry, nectarine and peach -- as well as the almond. They're all members of the extensive Rose family, which includes the apple, pear and strawberry. The fruit is classified as a drupe, defined by the hard stone pit surrounding its seeds.
There are dozen of species, but here's the lowdown on what you're most likely to find in the US marketplace:
P. Domestica: Also known as the European plum, which includes the prune plum, greengage and egg plum. Closely related are the damson and bullace, grouped under the subgenus P. Insititia.
P. Salicina , also known as the Chinese or Japanese plum, which botanist Luther Burbank (mentioned earlier) crossed with P. Domestica to create dozens of cultivars. Most supermarket plums in this country are such cultivar mashups. Santa Rosa, Burbank, El Dorado, Redheart and Friar are just some of the names you may have encountered. Burbank also developed the plumcot, an apricot-plum hybrid.
Then there are several wild plum varieties native to North America. The variety that intrigues this plum lover is P. Maritima, also known as the beach plum, which grows on sandy dunes along the Atlantic coast, from Maine to Maryland. Rather than a tree, the beach plum is more of a shrub about five feet high and produces small orbs around the size of a large cherry (so I'm told) in various shades of blue, red and yellow. The flavor is sweet-tart and astringent, and has been described as when a plum meets a strawberry. They are better used for preserving than eaten out of hand.
To know the beach plum is to love it, or so it seems. Because it grows only on sandy dunes -- and these days, protected on a small number of barrier islands -- the beach plum is either a stranger or a lover. Here's a 2012 video footage from Sandy Neck Beach Park, a barrier island on Cape Cod, at the height of beach plum season. It's caught the attention of regional food journalists -- here's one report from Long Island beach plum country and another from Westport, Massachusetts, another coastal beach plum oasis.
In recent years, there have been concerted efforts to cultivate or tame the wild plum. At the forefront of the beach plum revival is Dr. Richard Uva, a horticulturist who is interested in developing niche markets for beach plum products. On his farm on the Eastern Shore of Maryland, Uva has four acres of cultivated beach plums; last year's harvest amounted to more than 12,000 pounds of fruit. In an industry presentation to fruit farmers earlier this year, Uva noted that a group in Cape May, New Jersey, which has formed the Cape May County Beach Plum Association, is interested in beach plum cultivation to save and strengthen their sand dunes.
Other North American varieties are:
P. Subcordata, also known as Klamath, Oregon or Sierra plum, which grows in southern Oregon and northern California
P. Americana, aka the American plum, wild plum or Marshalls plum, which grows in the central states as well in the east
P. Angustfolia, aka Chickasaw, Cherokee or sand plum, which grows in the south
P. Nigra , aka Canadian plum or black plum
The past decade has seen the arrival of two additional apricot-plum hybrids, namely the Aprium and the Pluot, which is also sold as a Dinosaur Egg. For a deeper discussion on fruit hybrids, check out The Perfect Fruit: Good Breeding, Bad Seeds and the Hunt for the Elusive Pluot by journalist Chip Brantley.
According to 2011 FAO statistics, China is the world leader in plum production, followed by Serbia, Romania and Chile. The United States sits at number six. Here at home, California has long dominated domestic plum production, both fresh and dried. In 2010, the state produced some 141,000 tons of fruit; an additional 12,000 tons came from Oregon, Washington, Idaho and Michigan.
Traditionally, the plum is a warm (but not super hot) weather fruit that needs lots of sun but not lots of humidity. This is why they can grow in California several months out of the year. Depending on the variety and growing region, plum season can begin as early as May and go well into September. July and August are peak plum season in most parts of the country. August is typically when prune plums are harvested and dried.
As mentioned earlier, the lion share of supermarket plums is coming out of California, which means long-distance travel is required to reach produce aisles in all remaining 49 states. This one-state commodity set-up is a good argument to eat plums from your respective food shed and when they're in season. During off season, the US imports plums from Chile. In short, commodity plums, no matter what time of year, come with a heavier carbon footprint associated with shipping.
Of the 51 produced items analyzed in the Environmental Working Group's 2014 Shopper's Guide to Pesticides in Produce, the conventional plum received a rank of 17, which makes it closer to its "Dirty Dozen" club than to its "Clean 15." (See our Real Food Rule of Thumb, below.*)
Pesticide Action Network, which compiles pesticide data from the USDA, found 44 types of pesticide residues on conventional plums tested in 2012. Ten of those pesticides are toxic to honeybees.
According to watchdog group Beyond Pesticides, there are some 87 pesticides with an established tolerance for conventional plums, 75 of which are poisonous to wildlife, 16 which are known surface and ground water contaminants, 25 which are toxic to honeybees and 32 which are potentially hazardous for farmworkers.
Variety is the operative word here: Plums can be as small as a cherry (beach plum) and as big as a tennis ball (Santa Rosa), shaped like a football (Italian prunes) or squat, like a tomato (cherry plum). They come in shades of yellow (Mirabelle), Granny Smith apple green (green gage) or deep red with a green streak (Satsuma). Flavors ranges from super tart to honeyed, floral to melon. They all have pits, which also vary in size, but most are freestone (thanks to all the Burbank breeding). Try a few new to you and see what you think!
What to Look for
No matter which variety you choose, you want taut, firm skin (versus swollen). No bruising, discoloration or soft spots. You'll know your plum is ripe when it yields to a little pressure from your thumb. Unripe plums will ripen at home in a paper bag in the refrigerator.
Fresh plums are a good source of potassium and Vitamin C. A five-ounce plum contains more than two grams of fiber. Dried plums are loaded with fiber -- one-fourth cup contains three grams 12 percent of the daily recommended value. All that fiber is great for regulating blood sugar levels and feeling satiated (and perhaps eating less in between meals). They're also are a natural source of sorbitol, a sugar alcohol which can have a mild laxative effect on the body. Prunes are also rich in phenols, disease-fighting phytonutrients and have been studied for their potential to increase bone density and keep osteoporosis at bay.
The caveat: Prunes are high in oxalates, which can crystallize and are a potential risk for anyone with kidney or gallblader conditions. As always, check with your health care provider before including prunes in your diet.
What to Do with It
Get preserving, that's what! There are only so many plums you can eat out of hand. What follows is a bunch of ideas to enjoy plums into the cold months.
Given their short season, plums are a great excuse to put up and preserve:
- Make chutney for a cheese plate or your next roast beast.
- A batch of plum catsup to zip up the next grillfest
- Asian plum sauce that you can keep in the fridge or process in jars for the winter
- Plum schnapps for when it's really cold out
- Plum jam -- great for gifts at the end of the year
In her cookbook, Plum Delicious, Nani Steele suggests poaching plums in a vinegar brine scented with cinnamon, vanilla and allspice that transforms into a spiced syrup. She recommends pairing them with cheese or with with poultry or pork.
This summer, I'm planning to grill up a bunch of plums, halved and pitted, and brushed with olive oil. Once they come off the heat, I'll drizzle just a touch of honey, a squeeze of lime and some chopped basil. Or leave off the basil and top with a spoonful of Greek yogurt.
Keep in the refrigerator, and in a paper bag if you some ripening assistance. Plums should be eaten within a few days of purchase.
Plum Barbecue Sauce for Baked Beans (or Whatever You Like)
Adapted from Stone Fruit by Cynthia Nims
Fellow Seattle author Cynthia Nims cooks her sauce in a saucepan and then uses it to lacquer ribs or barbecued chicken. I love how it translates into a dish of baked beans.
3 tablespoons neutral oil
1 cup finely chopped onion (medium-size or large yellow onion)
2 tablespoons minced garlic (from about 5 cloves)
1 1⁄2 pounds fresh plums
1⁄4 cup molasses
1⁄4 cup tomato paste
1⁄4 cup brown sugar
1⁄4 cup red wine vinegar or cider vinegar
1 teaspoon salt
1 teaspoon of your favorite medium-heat chile pepper
3 15-ounce cans pinto and/or kidney beans, rinsed and drained (or 2 cups dried beans, cooked)
- Preheat the oven to 350 degrees. Prepare a 9x13 baking dish by lightly brushing the bottom and sides with oil or oil spray.
- Heat the oil in a medium saucepan over medium heat. Add the onion and cook until slightly softened, about 5 minutes. Stir in the garlic and cook for an additional 2 minutes, being careful not to burn it.
- Cut the plums in half, remove the pits and coarsely chop. Place the pitted plums, molasses, tomato paste and vinegar in a food processor or stand blender, and process until pureed. Add the brown sugar, the salt and ground chile pepper and blend once more.
- Transfer the sauce to a mixing bowl and add the beans and the cooked onion-garlic mixture. Pour everything in prepared dish and bake for 1 hour, or until bubbly. The beans should keep moist while they cook; cover with foil if necessary.
- Makes 6 to 8 side-dish servings.
(*Real Food rule of thumb: We think that first and foremost, in terms of nutrition, people should eat lots of fruits and vegetables whether they are organic or not. The EWG's guide is a handy list, but we will point out here that the impacts of pesticides are not limited to your ingestion of them - agricultural chemicals also affect farmworkers and local waterways, both good reasons to buy organic, even those vegetables that carry a light pesticide load. Also, it has been demonstrated that produce grown by small-scale farmers, even those who are not certified organic, tends to have a lighter pesticide load than its industrially-produced counterpart, owing to industry's tendency toward large monocrops.)
This post was originally published in July 2014.