Today, visitors to Jefferson's home in Monticello can see varieties of vegetable and flowers that Jefferson himself once grew. Some of the seeds planted at Monticello may be almost 200 years old, an awesome concept and a perfect example of treasured heirlooms. Each year, in December and January, commercial seed companies sell attractive, relatively inexpensive seed packets to home gardeners through seed catalogs and garden shops. Anything from root vegetables and beans to eggplant, tomatoes, and okra are available. Though these catalogs are filled with appealing color photographs of your favorite vegetables, what they're selling are hybrid seeds, seeds that have actually been bred for the commercial grower.
Hybridized plants are the result of a cross between two varieties.
For instance, two varieties of tomatoes are chosen because each has particular traits the grower wants to cultivate. When seeds are taken from the cross-pollinated tomato, these seeds will not be able to reproduce this crossed variety, but will revert back to one of the parents. Heirlooms, which are open-pollinated plants, on the other hand, reproduce themselves generation after generation. Commercial growers who grow only hybridized crops risk the danger of a fungus or plant disease destroying their entire crop. It happened in the famous Irish potato famine in the 1840s where farmers were growing only one variety of potatoes.