Collecting Seed at Home

Toward the end of summer, the seeds of many native plants in the Northeast begin to ripen and disperse. Seed for each species should be collected when it is ripe– too early or too late and the seeds may not be viable.

Collection guidelines:

1. Confidently identify the species
   Most plants are easiest to identify when in bloom.  Observation is key, noticing what the flowering stems look like after the show of flowers. Even in a home garden setting, species can get easily confused after their flowers have faded.
   

2. Do your research
   We cover some general germination and storage requirements below, but find out what each of your species need– improper storage or delayed processing can destroy a season of seeds.
   

3. Responsible collection
   To encourage a species to fill in and spread more naturally, limit seed collection to ~5% per individual plant. Collecting too much seed can lead to diminished populations and limited genetic diversity. However, if you want to prevent a species from reseeding itself around the landscape, remove all its seed, sow what you harvest, and plant the seedlings where you’d like them to grow. If a species is not filling in as much as you’d hoped due to site conditions, collect and sow more of its seed to build and diversify the population the following season.
   

4. Sow what you harvest
   Collect only as many seeds as you plan to sow.
   

5. Store leftover seed properly
   Dried seeds should be stored in a cool, dry, temperature-controlled location. We recommend storing any unused seed in tightly sealed plastic bags or glass jars in the refrigerator until the following season. Label each jar with the species name, collection date, and collection location. Keep in mind that humidity (like in a damp basement), temperature swings (like an uninsulated structure), and high temperatures (like a hot car) can damage seeds.

Seed Ripening & Collection:
Trees and Shrubs

Oaks: Collect acorns as soon as they fall (otherwise the squirrels will). Soak them overnight in a pail of water, discard the floating acorns, plant them immediately, and protect them from rodents with wire screens.

Maple: The wings of the green keys take on a dry, papery appearance, while the seeds remain green. Collect and sow them immediately, and protect them from rodents, who relish the seeds.

Ash: Fruits are long, thin keys with the seed at one end. They can be sown immediately or stored dry in the refrigerator until spring.

Birch: Small, dry seeds with thin wings disperse gradually from the catkins all fall. Store the seeds in a paper bag until sowing. 

Viburnum, dogwood, and aronia: These shrubs and small trees have clusters of fleshy fruits. Remove the flesh and sow the seeds immediately.

Wild rose: Pick the small tan-to-brown seeds out of the flesh. Sow in fall for the long, cold stratification needed for good germination.

Witch hazel: Tan capsules ripen in October when the shiny black seeds explode from the pods. The pods can be collected before they open and stored in a paper bag. The seeds pop out, which is entertaining to hear if you are nearby.

Wildflowers

Milkweed: Canoe-shaped green pods turn from pale green to yellow and split along one edge. Pick the pods and put them in a paper bag to dry.

Lobelia and penstemon: Dry, brown seed pods are filled with tiny brown seeds. Let them dry in paper bag before sowing.

Iris: Large, brown seed pods split into three parts. Store the seeds dry for fall sowing.

Canada mayflower, false Solomon’s seal, blue cohosh and Solomon’s seal: Harvest the fleshy fruits when they turn color (red or blue), remove the flesh, and sow immediately.

Wintergreen and partridgeberry: Split open the red fruits and pick out the small seeds. Seeds can be stored dry until sowing.

Coneflowers: Rub your fingers against the central cone and seeds will fleck off when they’re ripe. Store dry until sowing.

Aster, Joe-Pye weed, blazing star, and goldenrod: Flowers turn to fluffy beige seed heads. Gently rub your hand across these fluffy clusters and ripened seeds will easily come off. Put the seeds in a paper bag and let them dry for a couple weeks to “after-ripen” (a wild plant strategy that prevents seeds from germinating in late-fall warm spells). Germination is most successful with fall sowing.

A note on sowing fleshy seeds

We find that, with most species , trying to replicate how they best germinate in nature works well when growing in pots too. For many of our fleshy fruited species that means passing through the digestive tract of a bird or other vertebrate. We find collecting fruits in a plastic baggy and squishing them for a few days to a week can help mimic that process. You will likely notice the flesh starting to ferment the longer they are kept in the bag. We then wash off the flesh and sow immediately, not allowing them to dry out. 

Learn more about How to Sow Seeds.

For recommended propagation books, see our Books page.