Understanding Open-Pollinated Varieties and Their Role in Seed Preservation
Whether you are new to seed saving or looking to refresh your knowledge on the practice, these seed-saving basics are a recommended starting point.
Hybrids, resulting from the crossbreeding of two plant varieties, typically do not yield offspring with the same characteristics as the parent plant. Conversely, seeds obtained from open-pollinated varieties will give rise to plants that are identical to the parent.
Open-pollinated varieties will maintain their specific traits as long as they are crossbred within the same variety, similar to dog breeds. With proper attention and strategic planning, the seeds you produce will remain true-to-type, preserving their unique characteristics throughout generations as long as they do not cross-pollinate with other varieties of the same species.
Open-pollinated varieties come in different types: annual, biennial, and perennial. Annuals, like lettuce, tomatoes, and peppers, go through a single growing season where they flower, set seed, and then die. Biennials, such as carrots and onions, take two growing seasons and a cold spell before they flower. Perennials, like apple trees and asparagus, can survive and flower for many years.
A species is a group of individuals that can reproduce together. Most crops in the garden are different species, but not always. There are multiple species of squash and two species of kale that cannot cross-pollinate. However, Cucumis melo, commonly known as melon, includes some varieties sold as cucumbers because they are unsweet and sometimes pickled.
Planting only one type of variety within a species can ensure the preservation of pure seed. However, if you desire to save seeds from multiple varieties, having knowledge of the plants’ scientific names will assist in determining which ones might cross-pollinate. Preventing cross-pollination between two distinct varieties within the same species is essential for maintaining pure seed.
Squash can be categorized into three species: Cucurbita maxima, C. moschata, and C. pepo. These species do not usually cross-pollinate. However, plants like broccoli, Brussels sprouts, cabbage, cauliflower, collards, kale, and kohlrabi, all classified under Brassica oleracea, can cross-pollinate despite what one might assume. Make sure to research the cross-pollination habits of the plants you are saving seeds from to avoid any issues.
Having knowledge about the pollination process of garden plants can assist in preventing cross-pollination. Certain plants, such as tomatoes, peas, and beans, are capable of self-pollination even before their flowers have fully bloomed, reducing their vulnerability to cross-pollination. However, it is important to note that insects may occasionally still cross-pollinate these self-pollinators. On the other hand, plants like squash or cucumbers, which rely on insect pollination, and plants like corn and spinach, which are wind-pollinated, are more prone to cross-pollination.
To ensure that seeds are genetically pure, it may be necessary to take some measures in the garden to prevent cross-pollination between different varieties of the same species. For certain crops, such as lettuce and peas, simply providing extra spacing between varieties is sufficient. However, more advanced techniques like larger isolation distances, pollination barriers, or hand-pollination may be required for other crops.
Some fruits are ready to eat before their seeds are mature. Examples include carrots, cucumbers, eggplants, peas, green beans, summer squash, and cabbage. Take a carrot for example. After about two months, you can pull the sweet root out of the ground and eat it, even though the seed is not mature. The seed needs more time to reach maturity. When you harvest the seed, the carrot plant can be up to four feet tall and one year old. Seed savers should leave a few plants of these crops to fully mature in the garden if they want to save seeds. Dry-fruited crops like grains, lettuce, and beans can have their seeds removed once they are dry and hard.
Garden crops can be classified as dry-fruited or wet-fruited. Collecting seeds from dry-fruited crops is easy. Just pick a few mature seedpods from the garden and bring them inside to dry and clean. Wet-fruited crop fruits should be picked when the seeds are mature. Crush or cut open the fruit and extract the seeds from the flesh and pulp before drying them.
Seeds are happiest when stored in a cool, dark, dry place. A dark closet or cool basement are good spaces to store seeds for a year or two. Seeds can also be sealed in airtight containers and stored in the refrigerator or freezer for several years. Some crop seeds last longer than others. Tomato seeds and beans can be stored for many years, while onion and carrot seeds don’t last as long. Label your seeds with crop type, variety name, notes about the source, harvest date, and number of plants.