A decade ago, heirloom and open-pollinated, or OP, varieties of vegetables and flowers as well as certified organic seeds were the domain of small, regional seed houses. Today, most mainstream seed companies, such as Johnny’s, Stokes, Burpee, Park’s, Vessey’s, Harris, Thompson & Morgan, and Jung also offer these choices, a change that put many of those small, alternative companies out of business.

Some are still around, however, and new names appear regularly. If you want to try some blue-highway seed companies, to steal William Least Heat-Moon’s title, try some of these less-well-known seed sellers. Most but not all also publish a print catalog.

Marianna’s Heirloom Seeds: This family-owned Tennessee company grows and sells “extraordinary heirloom and Italian seeds,” hundreds of tomatoes, peppers, and eggplants. You can find tomatoes from near white to near black and both sweet and hot peppers, but even more special is the eggplant collection: 28 varieties in white, apple green, orange, amethyst, rose, pink, lilac, violet, and best of all — at least on the color scale — “electric purple with white clouds.”

Ronniger Potato Farm: The Ronniger family has been growing certified seed potatoes — “the best all-round bundle of nutrition known” — for more than 30 years. Theirs is a rainbow inventory, everything from ‘Red Thumb’, ‘Purple Peruvian’, and ‘All Blue’ to yellows like ‘Yukon Gold’, their bestseller. Traditionalists wedded to white-fleshed spuds can find plenty to like, including the heirloom ‘Early Ohio’ and ‘Atlantic’, guaranteed for potato-chip making.

Nichols Garden Nursery: Sixty years old this year, Nichols is still family owned and operated and still sells a topnotch manifest of seeds from its location in Oregon’s Willamette Valley. Gardening conditions there are the “best possible,” but its seeds — vegetables, flowers, but especially herbs — will grow anywhere. Even a Connecticut Yankee or a Georgia peach will love its agrimony-to-wormwood herb inventory. Where else can you find 22 basils?

Diane’s Flower Seeds: A new kid on the block, Diane Linsley also grows many of the seeds she offers, especially hard-to-find varieties. Heirloom, rare, and endangered flowers are her metier, but she also offers 100 heritage tomatoes and a small array of old-time vegetable varieties. Most special are her perennial flower seeds — achillea to viola — which are suitable for patient gardeners not demanding blossoms the first year.

High Mowing Organic Seeds: Tom Sterns, a hero of the sustainable farming and buy-local movement in Vermont, lists 450-plus varieties of certified organic vegetable seeds, a mix of heirlooms, OPs, and hybrids — plus a handful of flower seeds. What seeds Sterns can’t produce on his farm he purchases from other independent growers and a few wholesale seed companies that “stand out in terms of their commitment to organics.”

Filaree Farm: Filaree is a vampire’s nightmare: it produces more than 100 strains of certified-organic garlics on its 20-acre farm in north-central Washington. Order early, as “Sorry! Sold Out” is the catalog’s most frequent annotation for everything from ‘Aglio Rosso’, a Creole garlic from the Abruzzo region of Italy, to the the large, artichoke garlic ‘Chopaka Mountain’, described as mild “with a tingle.”

Gary Ibsen’s TomatoFest: Tomatoes — seeds for the “best tasting, non-hybrid, non-genetically modified, old-fashioned and rarest heirloom tomatoes from around the world” — are the stock-in-trade of this California firm. It’s a fest and a feast, and choosing from the many isn’t easy. The most-ordered varieties were ‘Chocolate Stripe’ and ‘Italian Heirloom’. Not your cup of tea? There are 598 alternatives.

Seeds Trust: “Vegetable, wild flower, native grass, and herb seeds for a sustainable future” remains the mantra for this company, now in its third decade. The warehouse operations have moved to Arizona from Idaho, but propietor Bill McDorman still focuses on cold-hardy, short-season varieties for people with their heads in the clouds. For a start, he offers “43 trialed, tested, and notably early and vigorous tomatoes,” most from Siberia.

Karan Davis Cutler is one of eight garden writers who blog regularly at Diggin’ It. She's a former magazine editor and newspaper columnist and the author of scores of garden articles and more than a dozen books, including “Burpee - The Complete Flower Gardener” and “Herb Gardening for Dummies.” She now struggles to garden in the unyieldingly dense clay of Addison County, Vt., on the shore of Lake Champlain, where she is working on a book about gardening to attract birds and other wildlife.

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