On an Norwegian archipelago in the Arctic sits the Svalbard Global Seed Bank. It is a highly secure doomsday vault built into the side of a mountain that houses nearly 1 million agriculturally significant seed samples from around the world. The idea being that if ever needed, humans would have access to the most important plants needed for food and survival. Let it be known that there's a seed bank, albeit not as important, that is much closer to home — and it's giving away free plants.
Unlike the maintained Svalbard seed bank, the soil in our garden acts like a natural seed repository. Birds, wind, water and the plants that came before have all been making deposits. Those deposits have been waiting for favorable conditions to occur before sprouting. Soil seed banks, which are of great ecological and economical significance, were first observed and studied by Charles Darwin in 1859. The species that sprout in our gardens, or in the natural succession of a disturbed site, represent the seeds that have been present in the soil for seasons, or possible even years. The extended longevity of seeds stored in dried conditions is addressed in The Encyclopedia of Seeds: Science, Technology and Uses, a book by J. Derek Bewley and Peter Halmer. Seeds from an array of species were found viable anywhere from 200 to 3,000 years old. Lambsquarters (Chenopodium album) is a common garden weed and its seeds can stay viable in soil for 40 years or more. If you know where and how to look and with a little luck, you can reap what has already been sown.
I have been lucky enough to have watched thousands of plants grow from seed, which has given me a familiarity with the cotyledons, or seed leaves, of many common garden plants and natives. While many of those seeds were purposely planted, I have gotten just as many freebies. Knowing which seedlings are which, or even being patient enough to let them grow to size, is a great way to fill your beds with plants adapted to your specific soil and light conditions.
The year my oldest daughter was born a dogwood tree seeded itself in my front bed. I've let it grow, though it is poorly positioned, with the intention of transplanting it to our next home. When I was doing commercial landscaping, I rescued a butterfly bush seedling from a parking lot and gifted it to a friend in Virginia Beach. And each spring I pot up a dozen coneflowers, ox eye and liatris to share with friends.
A great way to ensure a good crop of free plants is to leave ripened seeds in your beds. Deadheading often helps plants to keep blooming. A friend taught me to shake ripened seeds into the bed, or plant coneflower heads upside down, where seedlings are desired. When I'm working at a client's house or gardening with a friend, I always recommend leaving "weeds" until they can be identified. This reduces chemical applications as well as time spent hand weeding.
There are times when this isn't possible, like if you're tidying beds for a special event, but poorly placed "weeds" can be transplanted to more desirable locations — or even gifted to friends. Growing plants from seed takes patience, but it helps in identifying the free seedlings growing all around you.
In Full Bloom is a weekly feature from Allissa Bunner that focuses on sustainable gardening, environmental stewardship and related community news and initiatives. Bunner is a Norfolk resident who is passionate about plants — especially natives — and enjoys growing things from seed. She admits to a botany bias (blame the biology degree from Old Dominion University) and is working on becoming a well-rounded naturalist as she also teaches her two children to have a love for nature. She can be reached at email@example.com.