Written by: Molly Marquand
Go local: Over the course of the last decade, native plants have garnered a place in the spotlight of popular horticulture. However, most of the natives found on the shelves at nurseries and garden centers are derived from homogeneous seed stock originating in the Midwest, or, perhaps worse still, are problematic varieties, deficient in nectar, or altered in some other way rendering them unrecognizable to pollinators. Fortunately, some of the most robust and useful natives are easy to source and grow at home. Seed collection and propagation is a low tech, relatively easy endeavor that allows the home gardener to not only save a little money on plants, but to ensure that truly native natives representative of the genetic diversity extant in local populations are utilized in plantings. Using these kinds of plants—deemed ‘ecotypic’, or, ‘ecotypes’—creates more resilient communities of natives, and benefits the wildlife that have co-evolved with these species within this same unique, local environment.
Ideal collection targets: All species have unique collection, storage, and sowing requirements, but some are easier to take care of than others. Many dry-seeded (meaning, seeds not high in water or oil content, and not surrounded by a fleshy fruit) fall-fruiting species are also terrific candidates for use in native plantings and restorations. The goldenrods are critical nectar producers for migrating butterflies and pollinators out late on the wing—they’re also easy to collect and abundant seed producers. Many of the asters, from the woodland blue to the showy New England to the lesser-known downy aster, are similarly easy to collect and grow and will provide important ecosystem services to wildlife. Fall collection doesn’t have to be limited to herbaceous species, however, the fruit from trees and shrubs can require tricky cleaning or immediate sowing, as is the case with the viburnums, and oaks respectively. The following species are a good place to start to try your hand at cultivating local ecotypic seed collected from your own home region:
Solidago nemoralis (gray goldenrod)
Solidago bicolor (silverrod)
Eupatorium perfoliatum (boneset)
Eutrochium maculatum (joe pye weed)
Doellingeria umbellata (flat topped aster)
Asclepias syriaca (common milkweed)
Symphyotrichum novae-angliae (New England aster)
Pycnanthemum tenuifolium (slender mt. mint)
How to make a genetically diverse collection: Various organizations proffer different tips on how to capture the genetic diversity present in a population of wild plants, however, the gold standard procedure comes from the federal Seeds of Success Program (SOS). SOS counsels finding populations of 50+ individuals and collecting uniformly and randomly across fruiting individuals. No more than 10-20% of what’s available should be collected in order to leave something for the wildlife, from weevils to warblers, that depend upon the wild seed crop each year. During collection, take note of approximately what percentage of fruit has been damaged, is shriveled, or has been eaten. If it seems a majority of seed is non-viable, find a different population to target. In some seasons, particularly those affected by drought like the summer of 2022, seed set is very low, and almost the entirety of what’s available is consumed by seed predators. To ensure a full picture of any population’s genetic diversity, collect some seed early, right at the beginning of the fruiting period, mid-season, and right at the end too. Many fall seeding species have a collection window of a month or more.
Tools: The tools required for each seed collection vary from species to species but are generally low-tech and easy to procure. For hairy or bristly seed capsules, like those of hop hornbeam (Ostrya virginiana), gloves will be necessary. For most dry seed forming species such as those in the aster and goldenrod family, bare hands will do. As a general rule, fleshy, oily, resinous, or fruits with high water content such as the viburnums (Viburnum sp), the hickories (Carya sp) or any of the native roses (Rosa sp) should be collected into plastic ziplock bags to prevent desiccation. Dry-seeded species such as any of the goldenrods or asters, the Joe-pyes or bonesets should go into cloth or paper bags.
After-care and storage: Once at home, collections of dry-seeded species should be spread thinly on a baking tray or other surface in a well-ventilated, cool area out of direct sunlight. Oily, fleshy, or high water-content seed must be processed and planted immediately to prevent fungal infection and rot. Generally, for the home or small-scale gardener, these types of seed are much more challenging to store and will probably do best being planted straight away and sent outside to stratify naturally over the course of the winter. Once seed has been adequately air dried, and all vegetative material (stems, leaves, etc) and insects removed, some light cleaning is beneficial prior to storage to remove a portion of the strobile parts which could collect moisture. Most seed can be gently rubbed on a textured surface to remove the pappus or other non-fruit parts, and gently separated with a paintbrush or fingers. This doesn’t have to be done perfectly by any means- the goal is just to reduce some of the collection’s bulk. Dry seeds can then be stored in a cloth or paper bag, or paper envelope in a cool, dry, dark place. Make sure to label your collection with the species name, the date, and the location it was collection. To determine whether your collection requires stratification (which might entail 30-60 days in a sealed container in the fridge) refer to William Cullina’s ‘Wildflowers’ . This wonderful book will also tell you exactly how to do it. Alternatively, fall collected seed which requires stratification can be sown immediately into large flats and left outside through the winter to stratify naturally. Unstratified seed can be stored for several years in optimal conditions (dry, cool, dark) but will start to lose viability almost immediately. Seed is best utilized within the first couple of years post collection.
Seeds of Success protocol:
About the author:
Molly Marquand is a botanist, mother, and native plant enthusiast located in New York’s Hudson Valley. Through her work with the Mid Atlantic Regional Seed Bank, Molly has collected seed for numerous federal, state, and private initiatives including the effort to save imperiled ash trees, several species of threatened viburnum, North American orchids, and a long list of species useful in restoration work. Currently, she is working to return an old pool pad in her garden to a xeric-loving native plant paradise.