As you go to buy seeds, you're going to run into some terminology that you may not be familiar with.  Here's some definitions to aid you in getting the garden you want.

 

Organic - Organic seeds are seeds that come from certified organic plants.  The definition for an organic plant, with a few exceptions, is that a banned substance (synthetic pesticide, fungicide, genetically modified organism or GMO) has not been used for 3 years.  From the USDA website itself it means the agricultural product was free of "irradiation, sewage sludge, synthetic fertilizers, prohibited pesticides, and genetically modified organisms were not used."  

 

GMO - GMO's, or genetically modified organisms, are plants or seeds that have been modified to include genes that were artificially placed.  For example, if a gene sequence was known that can provide resistance to a particular pesticide, then that gene can be inserted into a plant.  This plant will now express the gene and become resistant to that pesticide. This makes the grower able to use that pesticide for pests, knowing that it will not kill the plant.  There is debate about the health consequences of using GMO's.  A more in depth analysis will be provided at a later time, suffice it to say here the FDA holds GMO's to the same safety standards of regular seeds. As long as they pass they are considered equivalent.

 

Hybrid - A hybrid plant or seed is not a GMO.  A hybrid is a plant that has been selected for by cross pollinating two varieties of a similar plant.  This cross pollinating will produce seed that can be used to grow a plant that combines the characteristics of its two parents.  This new improved plant, called an F1 hybrid, now has the desirable characteristics it was intended to have.  A downside to this however is when the seeds of this plant are used, the progeny are often inferior, and don't have the same improved quality.  This means hybrid seeds will need to be purchased annually (assuming you use the whole packet) to maintain a certain variety of crop.  The advantage however is these plants tend to grow quick, provide larger and more satisfying food, and can help to build confidence for new growers.  These types of seeds are sold in every big box stores like Lowe's or Home Depot and are easily found.

 

Heirloom - Heirloom plants are the old school way of doing things. These are plants that have been selected for by nature and farmer's for generations and will grow true to form progeny with each generation (assuming no cross pollination).  There are many staple varieties of crops that are heirloom and are grown for the deliciousness and vigor.  These seeds can be more difficult to find, and often can be found from seed catalogs and internet vendors.  The enormous advantage to these seeds are the variety they can offer.  Baker's Creek, an incredible heirloom seed company, offers for example 32 PURPLE varieties.  That doesn't include the red, black, blue, green, or other colors.  This can also lead to varieties which have taste and texture that you may never be able to experience from the grocery centers around you.  Heirlooms offer the absolute most variety for your plants.  These seeds however do tend to be a small amount more to purchase and can be a bit more difficult to grow, though that is not always the case.