As the growing season nears its end, many home gardeners have a wealth of seeds falling from fading flowers or left on their plates after a snack of fresh vegetables.

Some have unopened seed packets piled on a shelf in the shed. The seeds didn't get planted this year because of lack of time or space. While most growers advise against saving vegetable seeds from this year's harvest, some seeds can be saved from year to year. Consider these guidelines when thinking of saving seeds.

Most vegetable and flower seeds remain vigorous for three to five years when stored properly. To save leftover seed, keep it in its original seed packet. This way you still have the planting and care instructions. Place seed packets in a tightly closed glass jar and place the jar in a cool location. A refrigerator shelf is ideal, but a cool closet or the freezer also works well.

Seeds from some plants lose ability to germinate quickly. Vegetable seeds to purchase new every year include sweet corn, parsnips, parsley, onions, and okra. Flower seeds to avoid saving include delphinium, gerbera, viola and the Easter lily.

You can check your seeds' vigor by placing a few seeds between two layers of moist paper towels. Put the towels in a plastic bag and punch a few small holes in the bag so air can circulate. If only half the seeds germinate, you should throw out the seeds or sow them thickly to get a good stand.

Some gardeners collect seeds from their garden plants to use the next year. However, you should avoid saving seeds from plants. Seed saved from this year's hybrid plants produce plants next year that are of variable and lower quality. You could transmit diseases and insects into next year's garden through the seeds. Also, if the seeds aren't dried properly before storage, mold or disease could start growing.

Despite these problems, sometimes saving seeds is worthwhile. Perhaps the tomatoes in your front yard are from the seeds carried off a plant started generations ago by a great-grandparent.

Saving certain seeds allows you to grow heirloom plant cultivars or unusual, hard-to-find plants. You also can harvest seed from rare wildflowers and propagate these plants without disturbing the mother plant in the wild.

You'll have more success saving seeds if you save them from plants that pollinate themselves, rather than those pollinated by bees or other insects. Self-pollinating vegetables include beans, peas, lettuce, tomatoes and many herbs.

To save beans and pea seeds, let the seed pods fully mature and turn brown. Harvest the pods, let them dry for two weeks, and shell the pods. Store the seeds in a paper or cloth bag. To save lettuce and most herb seeds, harvest the seed stalks before the seeds completely dry out and fall to the ground. Dry the seed stalks in a paper bag for two weeks in a warm, dry place. Shake the seeds off the stalks and store under cool, dry conditions.

For tomatoes, pick the fruits when fully ripe. Cut out the pulp and store it in a sealed plastic bag to ferment at room temperature. After four days, you can easily remove the seeds from the pulp. Use a strainer and rinse the seeds. Set the seeds on a paper towel to dry for two days — in a sunny window — and then store them in a cool, dry place.

Plants whose pollen spreads from plant to plant, either by insects or wind, need special care to pollinate. Avoid trying to save seed from these plants, such as pumpkins or cantaloupe.

When shopping for seeds, consider the price of the seed as well as quality. Commercial seed companies produce high-quality seeds at a low cost. Don't try to skimp by using low quality seeds. Instead, use quality seeds and look for disease- and insect-resistant cultivars. When choosing flower seeds, look for those labeled as prolific bloomers, while also choosing for color, shape and size.

Jennifer Frohnapfel is a Master Gardener with the Penn State Master Gardeners of Butler County.