Collecting and storing seed

October 5, 2020

Orange flower and brown prickly seedhead, purple flower and scattered seeds, and small cluster of flowers and brown fluffy clusters of seeds. — Flowers, seeds and seed heads from Tithonia, anise hyssop and boneset (L-R).

Fall is a good time for collecting seed in Minnesota from plants that are summer bloomers.

Seed can be collected from a variety of different plants, even some of our larger woody plants like trees and shrubs. Seed will come true from some species and seed collected from hybrids will result in a variety of different, sometimes surprising, plants.

Collect seed by harvesting nuts, berries, catkins, pods, seedheads, cones, etc., about two months after flowering from healthy and vigorous plants.

Collect plant parts on a dry day and let dry in a warm, still location, like on a sunny window sill.
Mold and mildew are the biggest problem with seed collecting, so be sure the seeds dry well.
You can also hang branches of flowers in a paper bag and allow the seeds to drop into the bag as the flower heads dry.
As you collect the seed, place them in an envelope and label them clearly. Store the envelopes in a sealed container. Include a few silica desiccant packets to absorb any remaining moisture.
Some seeds, like magnolia, should be stored in damp peat moss or vermiculite in a plastic bag.
Store collected seeds in the refrigerator (about 41 degrees F).

Find out more about collecting and storing seed from the Royal Horticultural Society article Seed: Collecting and Storing.