Many wonderful varieties of vegetables and flowers can be easily grown from seed or purchased as transplants. But how do you decide whether to select heirlooms or hybrids? Is a hybrid better than an heirloom?

Hybrids are created by crossing two carefully selected parent plants that possess specific desirable traits. Parent plants may be chosen for disease resistance, compact growth habit or the superior taste of the fruit. The offspring, called an F1 hybrid, will exhibit characteristics from both parents. Hybrid plants are more adaptable to environmental stresses and they possess "hybrid vigor," ensuring better performance in the garden.

The disadvantage of hybrids is that seed saved from F1 hybrids will not yield offspring identical to the parents. In order to produce the F1 hybrid, the original cross must be made each year. The term F1 hybrid refers only to plants that have been hand-pollinated by breeders and does not apply to those that have been crossed in the wild.

Well-known garden tomatoes such as 'Celebrity,' 'Early Girl' and 'Better Boy' are F1 hybrids. These varieties produce larger quantities of fruit and are resistant to common tomato diseases such as verticillum wilt and fusarium wilt.

Fritz Mitnick, a master gardener and winner of the Post-Gazette's Great Gardens Contest, likens tomatoes to wines. There are different varieties for different purposes. Her favorite is a hybrid called 'Sunsugar,' a small, sweet-tasting, yellow variety. Mrs. Mitnick compares a sample of 'Sunsugar' to eating candy.

Heirloom plants and seeds continue to gain popularity because they nurture the nostalgic side of gardeners. We love to grow plants reminiscent of those found in Grandma's garden. Like fine furniture, a true heirloom, at least 40 to 50 years old, is a treasured possession lovingly passed down through the generations. The flowers of heirloom plants are pollinated by either insects or the wind, in a natural process described as open pollination. Since the plants have stable traits, seed can be collected and saved for subsequent years and it will produce offspring similar to the parents.

Martha Rial, Post-Gazette These heirloom tomatoes carry a distinctive look: 'Tigrette Cherry,' left, 'Garden Peach,' center, 'Yellow Pear,' top, 'Mr. Bacon's Russian,' bottom, and 'Cherokee Purple,' right. Click photo for larger image.

Heirloom plants are not necessarily native to the area where they live. They can originate in any parts of the world and sport some very memorable names. The 'Moon and Stars' watermelon from Missouri is one legendary heirloom variety. The dark green rind of the watermelon is speckled with tiny yellow spots (stars) and a larger blotch (the moon) that is several inches across. It can weigh more than 40 pounds when ripe and usually has scarlet red flesh, although there is a rarer variety with yellow flesh.

Another heirloom, the 'Mortgage Lifter' tomato, was selected in West Virginia in the 1940s. Appropriately named, its starter plants were sold for $1 each and paid off a $6,000 mortgage!

Many gardeners are familiar with heirloom varieties like 'Black Seeded Simpson' lettuce, 'Kentucky Wonder' pole beans and 'Black Beauty' eggplant. Popular heirloom tomatoes include 'Beefsteak,' an old standard variety with large fruit perfect for sandwiches; 'Roma,' a paste variety with thick flesh, and 'Rutgers,' a New Jersey heirloom that produces excellent yields and is prized for canning.

Barb Kline, master gardener and co-owner of Mildred's Daughters Urban Farm, sticks with heirloom varieties for her garden. 'Cherokee Purple,' a variety originating with the Cherokee Indians, is one of her favorite heirloom tomatoes. Approximately 10 to 13 ounces, the fruits have a dusky, brownish-purple skin, dark green shoulders and brick-red flesh. The taste is described as "kind of smoky or earthy" and deliciously sweet.

"It is definitely a different taste, complex and like no other tomato," Ms. Kline says.

There is a place in the home garden for both heirlooms and hybrids. Consider experimenting with some of the numerous varieties available at local garden centers or from local plant sales, including Phipps' May Market, in Mellon Park, May 19-21.