Herbs in a Swamp
"Impossible." "Can't do it," said the experts, when Suzanne Cannon asked about growing herbs commercially in southern Louisiana. Too hot and humid, she was told, too much rain, soils are too soggy. But she was undaunted, and after ten years of experimenting she's running a thriving business selling herb vinegars.
"Suzanna's of Louisiana" proudly announces a large painted sign on the winding river road in Pointe Coupee Parish, 30 miles northwest of Baton Rouge. Beyond it are 25 raised beds bursting with culinary herbs. At one time, you could have looked back and seen the Mississippi River from here, but the levee, a huge serpentine mound that snakes through the flat landscape for hundreds of miles to prevent floods, looms instead.
Suzanne, an energetic woman in her late 30s, has become a local herb expert. Neighbors, doubtful at first about these green, weedy-looking plants, now come to admire the beds, a mix of colored foliage, bright flowers, and odd bits of sculpture. They've also taken to the vinegars. "One woman came in to buy six bottles of the Creole Mix," Suzanne told me. "It's the secret ingredient in her husband's catfish recipe."
How to Unwater
Most herbs are native to the dry Mediterranean climate, so Louisiana sends them into culture shock. Water rules here. It can rain up to 60 inches a year, occasionally in deluges of 12 inches in a single day. The water drenches the soil, sitting in swamps and bayous that cover thousands of acres, and saturates the air, which can be at 90 percent humidity for months on end.
"You can water, but you can't unwater," says Suzanne. "The books say to plant herbs in loamy soil," she adds, but when rain pounds down with relentless tropical intensity, it compacts loamy soil until the roots can't breathe. Besides, the topsoil had been scraped off the garden area when the house was built, leaving a cement-like silt bed. Drastic measures were obviously called for.
Suzanne first dug a drainage ditch around her half-acre garden area, then laid out a series of beds that measure nine by nine feet--the length of the railroad ties she uses as borders--by nine inches high. After cutting down the weeds, she put the ties in place, securing the corners with nails, and covered the ground with several layers of newspaper. In each bed she mixed three parts builder's sand and one part peat. (She tried river sand, but it contained too much silt, which slowed drainage and brought along weed seeds.)
To keep the summer sun's reflected heat from burning plant stems, she uses a lightweight mulch that won't sink in the sand, usually shredded pine, cypress bark, or pecan shells. When the winds are strong (this is hurricane country), the plants lean against decorative cypress knees she's rescued from the river.
Trial by Murder
None of her books helped her select herbs to grow in this soggy spot, so Suzanne had to experiment. "When I get a new variety," she explains, "I take real good care of it for a year. Then I divide it and put the plants in different places--one in a pot under the eaves of the house, one in full sun, another in part shade. It's what I call trial by murder." She has found that trying these small changes in microclimate often makes the difference between success and failure, and if the plants don't thrive in any of the spots, she throws them out. "Lord knows," she says, "there are plenty more to try."
She direct seeds many crops throughout the year starting in spring, thinning the resulting seedlings. For annuals, Suzanne had to study timing. Some herbs (see section below) are best sown during the cooler winter weather, for example. Frosts are occasional in this zone 8 climate, and sometimes there's even snow, but most of the time winter temperatures range from 40 to 70? F.
Harvesting is a year-round task. Suzanne pinches shoots back at the main stem, which forces buds below to grow, resulting in a bushier, stronger plant. Harvesting single leaves of herbs shocks the plants," she notes. If she's harvesting an herb heavily, as she does basil, she'll feed it every two weeks with a weak solution of 8-8-8.
Basil, an annual, is sown in spring for summer harvest. Her favorites are the regular large-leaved Italian basil (Ocimum basilicum), lemon basil (O. b.'Citridorum') and O. b. 'Purple Ruffles', which she uses in clumps mixed with other herbs for color.
Cilantro or coriander (Coriandrum sativum), an annual that appreciates cooler temperatures, is succession-planted through the winter and harvested until the spring heat hits.
Dill (Anethum graveolens) also prefers cooler weather and Suzanne sows it along with her cilantro.
Garlic chives (Allium tuberosum) are an indestructible favorite, and an excellent choice for a Louisiana garden because "just about every recipe here calls for garlic and onions." Suzanne uses this perennial as a border, periodically cutting back the straplike leaves to three inches.
Lemon verbena (Aloysia triphylla) is her favorite herb. She loves to smell its lemon-lime fragrance when the wind blows and uses the leaves in teas and fruit salads. She starts this perennial from cuttings; it does best in a pot on the patio.
Parsley, both curly French (Petroselinum crispum) and Italian flat-leaf (P. c. neapolitanum), is a biennial usually grown as an annual. It has to be started in the fall, Suzanne says, because the seeds need several weeks of cool temperatures before they'll even germinate. Parsley grows well through the winter and, if shaded, can limp through summer, reviving in the fall.
Rosemary was fussy about drainage even in the soil Suzanne created, so she mounded up part of one bed 10 inches. Upright rosemary (Rosemarinus officinalis) is a better choice for her humid garden than the prostrate type, and the hill planting also ensures good air circulation.
Tarragon proved a real challenge. Common French tarragon grown in a patio container "looked as if someone had strangled it." Then she got something called Mexican tarragon from a woman in Florida. It's most likely Tagetes lucida, which is also called sweet mace, winter tarragon, and mint marigold. It has a stronger flavor, she says, and grows readily in the raised bed, going dormant in the winter, then coming back in spring.
Fighting Ants and Crawfish
"Some problems you can't do anything about," Suzanne says, showing me marks of ant bites on her hands. "These beds are ant condominiums. They just love it when I build them another one." She won't use any kind of poisons to kill the ants because "herbs concentrate chemicals in their oils." Suzanne adds, "To be honest, the ants aren't all bad. All that tunneling does loosen the soil. I hardly notice the bites any more."
Although she has her moments: "Last spring when everything else was flooded, I was threatening to get out the pistol to shoot crawfish, then plant rice." When she's not in the garden, Suzanne is usually planning next year's experiments or working on marketing her vinegars. When I asked about a recipe for an herb vinegar, she smiled and said no. "There's nothing a Louisianian likes more than a secret recipe."
Kit Anderson, a former editor-in-chief at National Gardening, received her doctorate at Louisiana State University.
Photography by National Gardening Association.