Bermuda Buttercup: Neither Bermudan Nor a Buttercup

Bermuda buttercup is one of the best-known names for a plant that evolved nowhere near Bermuda, and that is in no way related to buttercups. But  it is yellow, and it does grow in Bermuda. And confusing common name was born.

That island territory in the Atlantic, almost 2,000 miles off the coast of the United States, is one of several places on the planet that has submitted reluctantly to the ever-growing presence of Oxalis pes-caprae, better known in its native South Africa as suuring (“souring”) or Cape sorrel. There, “Bermuda buttercup” is unheard of.  You might also know it as African wood sorrel, or sourgrass, and you would not be wrong. Common names can be confusing, because they vary by region, but they do tell stories. Pull a thread, and see where it leads: As those names suggest, Bermuda buttercup is rousingly sour, like lemon juice, but intensified. And unlike real buttercups (in the Ranunculaceae family, which are toxic), Bermuda buttercup is really good to eat.

Photography by Marie Viljoen.

In its native South Africa Bermuda-buttercup-slash-Cape-sorrel grows abundantly in the Western Cape province. In the region’s Mediterranean climate this winter-blooming geophyte carpets open fields and disturbed ground, its flowers bright in the sunshine, or folded in the rain that greens the province in normal winters. But the plant is now globally at home anywhere that a Mediterranean climate prevails; if it can enjoy wet winters and dry summers, it will move in, and it will not leave. Despite not reproducing by seed, its bulbils are prolific and very hard to remove. Bermuda buttercup  seems to relish being dug up, and will spread even faster when unearthed.

In the United States, it is listed as a noxious weed in the damper parts of the West Coast. Australia is not happy to host it. It has spread across the entire Mediterranean. And yes, it grows in Bermuda, probably arriving with the British, who would have met it at the Cape of Good Hope around the late 18th century.

While I can find no facts (yet?) to substantiate a hunch of mine, I can’t help wondering whether Oxalis pes-caprae might have been eaten at the Cape as a remedy for the scurvy that plagued the crews of long-haul ships sailing between Europe and modern-day Indonesia. Scurvy is a Vitamin C deficiency, and one of the reasons for the establishment of a refreshment station at the foot of Africa in 1652 by the Dutch East India Company. Other Oxalis species contain Vitamin C—also called ascorbic acid (etymology diversion: ascorbic means anti-scurvy)—and Cape sorrel is known to be rich in minerals and amino acids. In this scenario, Indigenous people would have introduced the edible plant to Europeans.

So where does all that leave us, the eaters of meals, the makers of dinner? In its homeland, where cheerful Cape sorrel is welcome and wanted, it is traditionally cooked with lamb, in waterblommetjie bredies. Its sharpness cuts the richness of the slow-cooked meat and balances the earthiness of the succulent waterblommetjies (Aponogeton distachyos).

In my own cooking, when I have collected it on visits to Cape Town, I use Bermuda buttercup as a straightforward substitute for lemon juice. I chop it finely into smoked snoek sambals and pâtés, and stir it into the onion-sweet rice of smoorsnoek (a rice-centric dish made with the barracuda-like smoked fish).

Recently, I added the chopped stems to the marinade for butter chicken and stirred another spoonful into the simmering sauce. The bowls were wiped clean.

There is one cautionary note about eating Bermuda buttercup, and it is related to quantity. Like some other plants (sorrel, lambs quarter, and spinach come to mind), it is high in oxalates. Eating a large quantity, regularly, would be anti-nutritional (oxalates bind calcium, making it unavailable) as well as bad for ailing kidneys. If you suffer from any kidney problem, it is probably a food to avoid.

I use no more than a few tablespoons at a time, precisely because it is so sour. Any more would result in a permanent pucker.

Leafy Green Tart with Bermuda Buttercup

Recipe adapted from Forage, Harvest, Feast – A Wild-Inspired Cuisine.

Adaptable to any leafy greens, this crisp tart is delicious eaten hot, at once, or cold, at a picnic. If Bermuda buttercup does not grow where you live, substitute sorrel or sheep sorrel. If you use nettles for this tart, blanch them by covering them in boiling water and cooking for about 5 minutes (spinach and chard need much less water, but nettles have those stings).

Filling

1½ lbs spinach, or: Swiss chard leaves (use the stems like this), nettles, lamb’s quarter, amaranth, quickweed
3 Tablespoons chopped Bermuda buttercup stems
1 cup crème fraîche or sour cream
½ cup whipping cream
3 large egg yolks
1 large egg
¼ teaspoon salt
Black pepper, lots

Olive Oil Pastry

• 2 ¼ cups all purpose flour
• ¼ teaspoon salt
• ½ cup extra virgin olive oil
• ½ cup tepid water

The pastry does not need to rest or chill, so make the filling first.

For the filling: In a large pot bring an inch of water to a boil over high heat. Pack in the leafy greens and cover. Cook over high heat for about 2 minutes, then stir to redistribute the leaves. Cook for another 2 minutes. The leaves should be just-tender but vividly green. Drain them through a colander. Refresh with cold water, then squeeze them dry as possible in your hands. Now roll them up in clean kitchen towels to press out residual moisture. Chop the leaves roughly, and reserve.

In a bowl beat the egg yolks and whole egg with the crème fraîche, cream, salt, and about 15 twists of black pepper. Add the chopped greens and the Bermuda buttercup and stir gently to combine. Dip a finger in to taste for seasoning, unless the raw eggs bother you. In which case…don’t. Add more salt, if necessary.

For the pastry: Combine all the pastry ingredients in bowl and stir to combine. Form into a ball.

To assemble: Preheat the oven to 400°F. Oil, or line a baking sheet with baking parchment.

On a clean surface, roll out the pastry into a disc about 12 inches in diameter. Transfer it to the sheet. Using your fingers, turn up its edges, crimping them to form a lip to contain the filling.  Gently tip in the filling and spread evenly. Bake for 40 – 45 minutes until the pastry is crisp and the center of the tart is set.

See also:

• Grilled Swiss Chard Stems: The Only Recipe You Need
• Wild Lettuce Soup (And Other Soothing Bedtime Stories)
• Just Dandy: Served Wilted or Fresh, Dandelions for the Win