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Let's Talk About Hybrids and Standards

This article was published originally on 7/28/1993
Numerous plant seed choices are available to choose from each year at garden centers and from mail order sources. Of these selections, many are hybrids others are standard (open pollinated) varieties. What benefits are there to growing hybrid vs standard varieties? How are hybrids created? An article written by the National Garden Bureau answers these and other seed questions very well.

What is a Hybrid? People often think of a hybrid as a "blending of two different plants -- a little of this and a little of that, something like mixing red and white paint together to get pink. With paint, you can make a light pink or a dark pink depending on how much red or white you use. You may get exactly the shade of pink you want the first time, but unless you measure very accurately, chances are that you would have a hard time reproducing the exact mix again if you wanted to make more pink paint. (We'll come back to this in a minute.) Fortunately, hybridized plants are the result of much more specific cross breeding (mixing), and the results are much more specific as well.

A hybrid is the result of pollinating one specific variety of a class of plants with the pollen of another genetically different variety of that class. While a hybrid can occur by chance, within the seed industry hybrids are the result of the cross breeding of carefully chosen "parent" plants that produce "offspring" (seeds) that will have special characteristics.

To accomplish this very exacting pollination procedure, the parent plants that are selected to be the females and produce seed have their pollen bearing anthers removed and they receive only pollen from those plants that have been selected as their partners. This is done because most plants have both male and female parts and can pollinate themselves. By controlling the pollination process, this results in the offspring having genetic characteristics from both parents. The offspring (seed) of this cross is called an F1 hybrid (F1 stands for "first filial"). The seeds from this cross will produce plants that are very uniform in plant habit, and carry a combination of traits from the parent plants.

Why Bother with Hybrids? Obviously, with all the removal of anthers and hand pollination that has to be done to produce a certain hybrid, it is more time consuming and expensive than just letting plants "do their own thing." So why bother? Well, hybrids exhibit some very desirable traits that non-hybrids don't. And it could take years for the "ideal" combination of desired traits to happen by chance.

Some Benefits of Hybrids. Generally speaking, hybrids exhibit a wider adaptability to environmental stress, and more uniform characteristics than non-hybrids. This can mean earlier flowers or fruits and higher yields. And hybrids are very uniform in size and appearance, something home gardeners appreciate when planning a garden. And multiple disease resistance can result from a specific cross, meaning better garden performance and less likelihood that plants will be damaged or made unattractive by certain diseases in the garden.

For professional growers -- those who grow the bedding plants you buy at the store -- hybrids can have better germination vigor so that more plants survive the germination period and grow to maturity, and earliness and uniformity can mean a lot to a grower's production schedule. Improved disease resistance can mean fewer chemicals need to be used to control disease, and more plants will make it to market. Even though hybrid seed costs more than standard seed, a grower has a better chance of producing more salable plants of higher quality.

With F1 hybrids, the breeder of the variety can own an exclusive on that variety. The reason is that only the breeder knows exactly what two parent plants were chosen to be bred to produce the seed. Let's go back to our "pink paint" example. If you mixed a pink paint that everyone liked, and only you knew exactly what red and what white you mixed in what proportions, you would have an exclusive. Yes, others can experiment and try to come up with the same mix, but that is time consuming and expensive -- just think of how many different reds and whites there are. In a way, it is the same with plants. Other breeders can try to duplicate a hybrid, but only the first breeder knows the exact combination that was used. Of course, it is through the process of trying to breed new and better varieties that new ones are found. Not every F1 hybrid is a winner.

What About Standard Varieties? Standard or "open-pollinated" varieties are varieties that have more or less stabilized in their habits from one generation to the next. These varieties are usually grown in fields where they self and cross pollinate. Wind and insects carry the pollen from one plant to another, and the seeds that result will produce plants that are fairly similar, but not usually as uniform as hybrids. Because genetic "drift" can occur in open pollination, meaning that plants are significantly different from the others can sometimes crop up, the fields have to be checked for "rogues" and the "off" types have to be pulled from the field so that they don't pollinate other plants and cause too much variation.

Because standard varieties are easy to reproduce, breeders can "patent" a plant under the Plant Variety Protection Act of the U.S. Department of Agriculture. This allows a seed company or breeder to control the sale of seeds of a protected variety, and encourages the development of new standard varieties.

The Choice Is Yours. Gardeners can choose hybrids or standards, in fact there are certain classes of plants that have not been hybridized, and there are also certain classes that are available as both standards and as hybrids (see lists). The most intelligent choice is made based on the performance of a variety in the garden, and in many cases the best performance will be from a hybrid.

Classes Available as Hybrids and Standards
Beets Eggplant Squash (summer, winter)
Cabbage Onion Sweet corn
Carrots Peppers Tomatoes
Cauliflower Pumpkin Watermelon
Cucumber Spinach
Dianthus Primula
Pansies Snapdragon
Portulaca Zinnia
Classes Not Hybridized
Beans Popcorn green, yellow, purple Ornamental Corn Bush Lettuce Pole Leek Lima Radish Snap Peas Herbs English Peas
Alyssum Gazania
Balsam Gomphrena
Browallia Lobelia
Calendula Marigold, Dwarf French
Celosia Nasturtium
Cleome Phlox
Coleus Salvia
Cosmos Verbena
Dahlia Vinca
Dusty Miller
Classes Primarily Offered as Hybrids
Ageratum Eustoma (Lisianthus)
Begonia Marigolds (American or African)
Geranium Nicotiana
Impatiens Petunia
(Taken from "Today's Garden," National Garden Bureau, 1311 Butterfield Road, Suite 310, Downers Grove, Illinois 60515.)

This article originally appeared in the July 28, 1993 issue, pp. 1993 issue, pp. 127-130.

Year of Publication: 
IC-465(20) -- July 28, 1993