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Understanding Seed Catalogs

It is that wonderful time of the year when the seed catalogs have arrives in the mail. Filled with striking images of good things to come, as you read the catalogs you may run across words that are unfamiliar. They are used to help readers make good decisions and buy the right seeds or plants for your garden. Let’s go over what these words mean so you will be a better informed gardener.

gaHardiness zone – The United States is broken up into hardiness zones based upon the lowest average winter temperature for the area. The zones are based on the average annual minimum winter temperature, divided into 10-degree F zones. Knowing what zone you garden in and seeing what zone the plant is hardy to will help you pick plants that should survive the winter. When you see a perennial offered for sale, don’t just look at the pretty picture; make sure it is at least hardy to your zone.

Determinate and indeterminate are words often associated with tomatoes. They refer to how large the plants get and how they grow.  Determinate types tend to stay more compact and bushy, do well in cages, and are well suited for smaller space gardens. The indeterminate types tend to get tall and just keep getting taller over the summer. They usually require staking and stringing to keep them off the ground. These are good for the gardener wanting tall, large plants to impress the neighbors.

Hybrid (F1) and open-pollinated (OP) are words that are used with both flowers and vegetables. Seeds of hybrid varieties are produced by the controlled crossing of known parent plants, resulting in varieties that exhibit the best characteristics of both parents. Often they are more vigorous, have better disease resistance, are more tolerant of adverse growing conditions, better tasting, and more uniform in habit.  In short, they are the best that plant breeders and seed companies have to offer and are well worth the extra money.  Open-pollinated is often associated with heirloom or antiques varieties of flowers and vegetables.  They are not the result of controlled crosses. While they may not exhibit the best disease resistance or uniformity, they bring to the garden interesting plants that might have been stars in your grandmother’s garden. These are well worth keeping because of their flavor in the case of vegetables or fragrance in the case of flowers.

Days to harvest, usually shown in number of days, refer to the average number of days it usually takes after you set out transplants before you can expect your first harvest. This is highly variable and depends on growing conditions so take the number with a grain of salt.

Award winners are often designated by terms such as AAS (All America Selections), PPA (Perennial Plant Association winner), and Fluoreselect. This indicates that these varieties have been trialed for many years in trial gardens through the United States and have been shown to be outstanding performers.

Disease tolerance and disease resistance are both good things but have different meanings. A plant listed as disease tolerant will probably get a disease common to the plant. It may not, however, be so bad as to warrant spraying and it usually does not affect appearance all that much.  Disease resistance means that the plant has been bred to resist common disease problems and will probably not get the disease. A common example is roses: you will find roses listed as both disease resistant to black spot and those listed as disease tolerant to black spot.

Some vegetables such as vine crops and tomatoes will include codes referring to disease resistance. Some of the main ones to watch for on tomatoes for instance are TMV (tobacco mosaic virus), TSWV (tomato spotted wilt virus), V (verticillium wilt), and F (fusarium wilt).

Most seed companies have web sites where you can order their catalog or shop on-line. Seed catalogs are a good way to get a wider selection than usually is available in local nurseries or garden centers, especially if you are looking for new or unusual varieties. Many seed catalogs include lots of cultural ideas and helpful pointers that will make you a better gardener. Remember not to get carried away with more than you and your garden space can handle – many seeds will retain viability for multiple growing seasons is stored on a cool, dry location.