Bernard McMahon

Bernard McMahon or M'Mahon (Ireland ca 1775 — Philadelphia, 18 September 1816) was an Irish-American horticulturist settled in Philadelphia, who served as one of the stewards of the plant collections from the Lewis and Clark Expedition and was the author of The American Gardener's Calendar: Adapted to the Climates and Seasons of the United States (1806 and following years). He circulated the first extensive gardener's seed list in the United States, which he attached as an appendix to his Calendar.

McMahon's most enduring contribution was his Calendar, the most comprehensive gardening book published in the United States in the first half of the nineteenth century. It finished in its eleventh edition in 1857. It was modeled on a traditional English formula, of month-by-month instructions on planting, pruning, and soil preparation for the "Kitchen Garden, Fruit Garden, Orchard, Vineyard, Nursery, Pleasure Ground, Flower Garden, Green House, Hot house and Forcing Frames". In some particulars, McMahon followed his English models so closely that J. C. Loudon suggested in 1826 that the derivative character of the Calendar was such that "We cannot gather from the work any thing as to the extent of American practice in these particulars." Ann Leighton notes the absence of Indian corn among the "Seeds of Esculent Vegetables" in 1806, though he lists old-fashioned favorites like coriander, corn-salad, orach, rampion, rocambole and skirret.

McMahon emigrated in 1796. By 1800 he was in Philadelphia, working for William Duane and the newspaper the Aurora. He entered the nursery and seed business c. 1802, when he issued his broadsheet Catalogue of Garden Grass, Herb, Flower, Tree & Shrub-Seeds, Flower Roots, &c which comprised 720 species and varieties of seed. This was the first published seed list in the United States.