Seeds were one of the colonists' most precious possessions. They saved each fall's seeds to plant the coming spring. Seeds were often saved in bags & nailed to a rafters to keep them high enough to protect them from hungry rodent interlopers.
In January of 1773, George Washington signed a 1 year contract with his gardener David Cowan (1742-1808). The contract listed some of the work to be completed & deliberately detailed his seed-saving duties, "he will, work dully & truely, during that time at the business; as also when need be, or when thereunto required, at the businee, empoly himself in Grafting, Budding, & porining of Fruit Trees and Vines-likewise in Saving, at proper Seasons, and due order, Seeds of all kinds." For this he was to receive "Washing, lodging, and Diet."
Cowan was a Scottish-born gardener who came to the colonies to serve Washington at Mount Vernon in 1770; but when the Revolution started, Cowan served as a lieutenant in the Royal Navy. He went on to serve in the Provincial Marine for upper Canada, commanding ships in the Great Lakes, where he later served in the legislature.
The process of saving seeds was never the same from year to year, as it depended on the weather; & there was always an element of risk involved. Excessive warmth & moisture could destroy seeds that had been dried to save overwinter. Heat & high humidity encourage fungi, molds, & bacteria which destroy the seeds' viability.
Colonial families grew most of their vegetables & herbs in the kitchen garden. In the spring & again in the fall, they planted the seeds of their cool weather crops such as broad beans, cabbages, kale, lettuce, mustard greens, onions, parsnips, peas, radishes, spinach & turnips. As the warmer months approached, they set out seeds for their summer crops such as pole beans, beets, carrots, cucumbers, okra, potatoes, muskmelons & watermelons, as well as seeds for their fall crops of squash & pumpkins. Seeds of perennial herbs were tucked here & there in the garden for flavoring food & fighting disease.
The period from the end of January until the middle of March was sometimes referred to as the Six Weeks of Want. Some years this precarious span of time lasted much longer than 6 weeks. By this time, most stored vegetables had been eaten, but planting had not yet begun.
Early spring greens, both cultivated & wild, could satisfy the family's craving for something fresh after months of pickled & salted foods. Throughout the entire growing season, the family preserved vegetables for the winter hoping they would last until the new plants began to appear.
Almost any vegetable could be pickled in a vinegar or salt brine with spices. They preserved some vegetables, like peas & beans, simply by drying them. Most root crops like carrots, beets & parsnips could last for months buried in damp sand in a cellar or yard, if squirrels & rodents did not discover their existence. Pumpkins, squash & onions could be stored in a clean, dry place such as the loft in the farm house, where next year's seeds might also hang in bags waiting for the spring season.
Because seeds from this period were not hybridized, but reproduced naturally through pollination, colonial gardeners attempted to keep their seeds pure & prevent cross-pollination with other species.