I recently went to Lübeck, the northern-German city on the Baltic known as the home of Thomas Mann and marzipan, and, with less enthusiasm, as a home of herring. I was fulfilling a longtime desire to see herring, one of the world's most underappreciated fish, being caught and salted in a city whose fortunes were built on it nearly a thousand years ago. I was also after a definitive version of potato salad—"one of the great triumphs of traditional German cuisine," as Horst Scharfenberg says in The Cuisines of Germany, and a particular specialty of the restaurant-owning couple I visited, who, like most of their compatriots, seldom serve herring without potatoes.
I arrived in time to go out with the last herring expedition before local fishermen headed to colder waters for the summer. And I absorbed very useful salad-making tips from a woman descended from a line of professional women cooks. The surprisingly light and intensely flavored German potato salad—tangy from vinegar and subtly oniony, with the note of sweetness common to all the region's salads—comes as a revelation to people used to bland, mayonnaise-slathered salads that weigh down plates at barbecues. (It's a far safer picnic and buffet dish, too, given that warm mayonnaise is an ideal bacteria-growing environment.)
The seemingly inbred ability to make good potato salad may result from the German appreciation of many kinds of potatoes and how best to use them at different times of the year—appreciation and knowledge anyone can gain by visiting farmers' markets now and in the next few months. Most of the heirloom potatoes that appear at farmers' markets are waxy, or low-starch, potatoes, quite different from big, thick-jacketed baking potatoes. Waxy potatoes are good for salads because they hold their shape when boiled, their high moisture content means a creamy texture, and they usually have better flavor than their mealy cousins. The newly popular fingerling potatoes, named for their shape (there are many varieties), are almost all low-starch potatoes, good for steaming, boiling, and roasting, and ideal for salad.
Truly new potatoes, which usually appear at farm stands from mid-August through September, are delicate of flavor and fragile of skin. They haven't even formed their final skin, in fact, and the flaky, evanescent flaps rub off as you touch them (the test of a new potato); they should be rinsed gently rather than scrubbed. It's best to season new potatoes very lightly, to appreciate their fugitive flavor and just-getting-firm texture. The writer Barbara Kafka steams new potatoes over medium heat in a generous amount of butter in a heavy, closely covered pot (she uses enameled cast iron). She frequently shakes the pot to prevent the potatoes from sticking, and does not lift the lid to check for doneness until the potatoes have cooked for a full half hour, so as to keep in the steam. A pot of these very lightly carmelized and intensely fragrant potatoes, just off the stove and uncovered at the table, can bring anyone back to the virtues of butter.
By late September to the beginning of November potatoes of all kinds have become their true selves, and are ready for salads and stronger seasonings. Most potato growers "cure" potatoes in dark, cool areas for several weeks before shipping them, so that they will withstand storage until the next season. Any potatoes from a local farmers' market will be superior to the long-stored ones from a supermarket, and the more dirt the better: industrial washing usually means potatoes from afar. If a farm in your area is selling heirloom varieties, look for Ozette, the best-tasting of the dozen or more fingerlings I've tried over the years; Ratte—also called Reine—are lovely too. Happily, a golden color usually means more than just a cosmetic suggestion of a buttery, rich flavor. (Color association also holds true with blue potatoes, this time negatively; people are generally averse to blue foods, associating them with mold or anomaly, and I've never found a blue or purple potato that tasted anything other than watery, bland, or musty.) Yukon Gold, not a fingerling but a medium-starch, general-purpose potato, is widely available year-round and is also a fine choice for salads. The small, round white- or red-skinned potatoes often mislabeled "new" are low-starch and will keep their shape nicely after boiling—although how much flavor they have depends on variety, distance from the farm, and length of time in the bushel basket.
"What's new and in season goes together," Lothar Tubbesing explained to me in the kitchen of the beautiful Baroque mansion in Lübeck where he and his wife, Heike, live and work. Heike was putting a pot of water on the stove—not for the potatoes, which she had already boiled and sliced, but for the dressing. The couple tries to serve only local seasonal produce at their restaurant, Lachswehr, on a site that has been occupied by an inn or a restaurant since 1188. The very tall, lean Lothar takes great pride in Lachswehr's history—and, indeed, in Lübeck's. Two of Germany's sprightliest odes to May were written in the garden behind Lachswehr, one of them set to music by Mozart, Lothar told me, breaking into song. When he showed me around the beautifully preserved medieval and Renaissance town center, which looks like the setting for a Vermeer, he seemed more like the mayor than a restaurateur. I wasn't surprised to learn that he and his wife would be catering a big birthday party for the real mayor the following day.