Understanding Seeds: A Winter Guide for Gardeners

January is a good month for hibernating and browsing seed catalogs. As you flip through the pages, you can warm yourself with thoughts of sunny summer days and fresh, ripe tomatoes. Here is a refresher on plant seed basics to help get you started on your summer garden planning. 

➜ What Is a Seed? 

A seed contains all the genetic information needed to develop into an entire plant. It contains an embryo, or tiny plant, packaged with its own food supply, called the endosperm. The endosperm may be made of proteins, carbohydrates, or fats, which feed the tiny sprout until it can begin photosynthesis. All of this is protected within a hard outer covering called the seed coat. The seed coat protects the seed from disease and insects and prevents water from entering the seed and initiating germination before the proper time. 

➜ Understanding Seed Packet Information 

Seed catalogs and seed packets provide a wealth of information on a plant’s life cycle and preferred growing conditions, including plant hardiness zone, days to maturity, and optimal soil temperatures. Understanding the terms you see in seed catalogs will help you make the best choices for your summer gardening goals. 

The plant hardiness zone is based on the average extreme minimum winter temperature. It is the standard by which gardeners and growers determine which plants, especially perennials, are most likely to thrive in a given location. The USDA publishes the Plant Hardiness Zone Map at planthardiness.ars.usda.gov. In North Dakota, zones range from 3b (–35 to –30°F) in the north to 4b (–25 to –20°F) in the south. 

“Days to germination” refers to the number of days it takes a seed to sprout after it is planted and watered. “Days to maturity” means the average number of days until the plant is ready for harvest. North Dakota gardeners often prefer varieties with shorter times to maturity, as soil temperatures typically do not warm until late May and frosts in both spring and fall can be unpredictable. The North Dakota Agricultural Weather Network (NDAWN) provides detailed historical information on the number of days each year between the last spring and first fall 32°F freeze at ndawn.info/climate_frost.html. 

Other information you’re likely to find on a seed packet or in a catalog includes whether a plant is an annual (one growing season), biennial (requires two years to mature), or perennial (grows year after year). You’ll also find guidance on whether the plant should be sown directly into the ground or started indoors, along with recommended planting depth and spacing. 

➜ Seed Viability and Storage 

Many seed packets include the date the seed was packaged for sale and the germination rate. Seeds typically have the highest germination rates in the first year or two after harvest, with rates declining after two or three years. Seeds will germinate best if stored in cool, dry, dark conditions and protected from insects and rodent pests. For longer-term storage, seeds can be kept in a freezer, provided they are completely dry and protected from moisture and condensation. In the Svalbard Global Seed Vault over 1.3 million seed varieties are stored at 0 °F preserving 13,000 years of agricultural history and plant diversity.  

➜ Hybrid, Open-Pollinated, and Heirloom Seeds 

Seed catalogs and packets also indicate whether a plant is a hybrid or an heirloom variety. To use this information effectively, it’s helpful to understand the terms hybrid, open-pollinated, and heirloom. 

Hybrid seeds are bred commercially for specific traits. Selected parent plants with desirable characteristics are crossed through controlled pollination. These seeds are often labeled “F1” or “F1 hybrids.” The terms hybrid and F1 are strictly defined in the seed industry and do not apply to plants that cross naturally in the wild. Hybrid plants tend to be uniform, vigorous, and high-yielding and are often bred for traits such as disease resistance or earlier harvests. The primary disadvantage is that seeds saved from hybrid plants will not produce consistent results, often reverting to traits of earlier generations. 

Open-pollinated seeds are produced through natural pollination by insects or wind. The resulting plants show greater variation. Heirloom seeds are open-pollinated varieties that have been saved and passed down through generations. They are valued for their diversity, uniqueness, and flavor and are often well adapted to local growing conditions. Saving heirloom seeds promotes biodiversity by preserving genetic diversity (variation) in plants. However, heirloom varieties may have lower disease resistance, smaller yields, and less uniform ripening compared to commercially bred hybrid varieties. 

➜ Saving and Sharing Seeds 

Many home gardeners save seeds from year to year, especially from varieties that perform well in their specific growing conditions or that they value for flavor or storage quality. Gardeners can explore new varieties, support biodiversity and build community by swapping seeds with others.

🌱 Local Seed Swap Opportunities

In the Minot area, the Ward County Master Gardeners are celebrating National Seed Swap Day with a community seed swap on Saturday, January 31, 2026, from 1:00 to 3:00 pm at the Ward County Extension Office. Light refreshments will be provided, and Master Gardeners will be available to answer questions about seed saving, gardening, and best practices for labeling and storing seeds. Attendees are encouraged, but not required, to bring seeds in clearly labeled packets with the crop name, variety, and year collected to make swapping easier for everyone. 

You can also participate in a virtual seed swap hosted by the North Dakota sustainable agriculture nonprofit FARRMS by joining their Facebook group FARRMS Virtual Seed Swap (www.facebook.com/groups/farrmsseedswap). Here you can exchange seeds through the mail and enter to win giveaways. Whether you’re looking for/sharing varieties that are adapted to our northern climate or just want to clear out your surplus, this seed swap is a great place to do so! 

As winter lingers, a little time spent learning about seeds and sharing them with others can help set the stage for a productive and joyful garden in the months ahead.