Growing Native Plants from Seed

Growing Native Plants from Seed Native plant seeds germinate best when treated as naturally as possible. Observe the natural process of seed dispersal and germination to replicate as closely as possible. Below the following tips, you’ll find some specific directions for an assortment of native plants. Seed Germination Tips • Many native seeds must experience a long period of cold in order to germinate. Simulate this cold period by using a refrigerator or by simply planting in fall and letting the seeds overwinter in “flats” (shallow trays). • Other native seeds depend on wildlife to open fleshy seed cases. These seeds need to be macerated (softened) and the pulp separated. • Native plant seeds benefit from a stable soil temperature. Covering seed flats with shredded leaves of the parent plant offers protection from the elements. In addition, partly burying flats in soil or bark can help to further stabilize soil temperature. • Protect seeds from birds, slugs, rodents and insects with seed cloth (also called, row cover or ‘Reemay’). • Do not allow seeds to dry out, while also making sure the flats are not kept saturated. Placing flats under eaves, under deciduous trees, or other such partial protection may be beneficial. • Once seeds have germinated make sure flats have plenty of air circulation and are watered regularly while avoiding over saturation. Provide sun/shade conditions that replicate the needs of the particular species. • Transplant into 4” pots, or directly into the garden, once seedlings have at least 2 sets of mature leaves. Douglas Iris Iris douglasiana In fall, sow seeds in flats in a cold frame (a bottomless box covered with glass or transparent plastic) or protect by seed cloth. Cover to twice the depth of seed. Plant out late summer/ fall. False Lily of the Valley Maianthemum dilatatum Separate seed from pulp. Sow in flat outside filled with humusy mix and winter over or prechill by placing them in your refrigerator for -5 days. Germination occurs in spring with the seed leaf showing about a month after the root develops. Most successful in moister humus-filled soil though it tolerates considerable dryness. False Solomon Seal -Smilacena racemosa Sow in humusy soil mix. Cover to 1/4” deep. Needs dark to grow. Dry storage can help germination followed by a cycle of warm, cold, warm for best results. Roots grow first. Goatsbeard Aruncus dioicus (sylvester) Fall to late winter, scatter seed in flats on potting soil. Cover with light layer of leaf mulch, seed cloth or cold frame to protect. Or, hold seeds in refrigerator over winter and direct sow once soil is warm. Goldenrod Solidago canadensis Easy to germinate. Surface sow fine seed on general mix. Cold period not needed but OK. Germinates in 2-3 weeks at 55-70 degrees. Grass species Gather seed in late summer and fall. Direct sow in flats or tubes in fall through late winter, or, dry, store, and plant in early spring. Germinates by spring. Easy to transplant directly to site. Oceanspray Holodiscus discolor

Collect seed in fall, viable seed usually less than 10%. Sow in fall to overwinter. Scatter seeds generously in flats on planting mix. Gently pat into soil, scatter lightly with dusting of potting soil. Cover with seed cloth. Germinates over spring and summer. Pearly Everlasting Anaphalis margaritacea Easy to germinate. Hold seeds over winter in refrigerator. Sprinkle seeds over potting soil in flats in spring, or direct sow in early summer.. Transplant when large enough to handle. Red Columbine Aquilegia formosa Germinates well from seed. Sow in fall or prechill for 3 days. Scatter evenly in flats, or direct sow. Cover with thin layer of soil. Keep moist. Cover with seed cloth (or place in cold frame) to protect. Sedge Carex species In fall, gather seed heads and separate seeds. Sow directly in fall, shallowly to the depth of seeds, in flats of potting mix, or in tube trays. Cover with seed cloth. Keep wet through winter. Germinates in early spring. Vine Maple Acer circinatum Collect winged seeds in fall. Separate ‘helicopters’ into separate winged seeds. Plant seeds thickly in rows by ‘nosing’ the winged seed into deep flats of planting mix about 3/4” (some of the wing will still be showing). Cover with shredded maple leaves and seed cloth. Germinates in spring. Transplant in one year. Wild Rose Rosa species Separate seed from pulp. Sow seed in general seed mix and cover to depth of seed. Prechill 6-8 weeks or overwinter out of doors. Germinates slowly in warm temperatures in spring. Western Red Cedar Thuja plicata Gather cones in fall. Allow to dry at room temperature for several days to open the cones. After drying, shake the seeds out of the cones. Sow in fall or spring on flats of loose soil. Cover with light layer of forest duff. Germinates in spring. Keep seedlings in shade during first year of growth. Yarrow Achillea millefolium Collect seed heads in late summer/ fall. Allow seed heads to air-dry indoors for at least a week before cleaning. Crush with a rolling pin to remove the nutlets, Sow indoors in late winter or sow outdoors in April.

General Seed Propagation Directions Planting tiny/fine seed: 1. Put a plug tray into a flat or use a full flat. 2. Fill the plug tray or flat with soil. 3. Gently drop flat to settle soil (do not pat or press). 4. Add soil if necessary to ¼” below top. 5. Evenly spread seed over surface of soil. Do not spread too thick or thin, remember up to 90% of the seeds may germinate. 6. Cover seeds with a sprinkling of fine soil. It is okay if some of the seeds are visible. 7. Create a label with seed type and date. 8. Cover flat with seed cloth and hold in place with clothes pins. 9. Water gently with a mister or fine sprinkler. Planting medium to large seed: 1. Fill a flat with potting soil. 2. Gently drop tray to settle dirt (do not pat or press). 3. Add soil if necessary, fill to ¼’ below edge of flat. 4. Create seed planting rows 2’ apart, depth should be equal to size of seed. (use a stick or pencil to create rows). 5. Place seeds carefully in row, seeds should be evenly spaced. About ½ to ¾ of the seeds should germinate so don’t plant too thick or thin. 6. Cover seeds with soil equal to the thickness of the seed. 7. Gently press soil over the seed. 8. Make a label with plant seed name and date. 9. Cover flat with seed cloth and hold in place with clothes pins. 10. Water flat gently (spray bottle or fine sprinkler is best) Planting Seeds with Wings (Maples, Ash): 1. Place 4” pots in flat or fill full flat. 2. Fill pots or flats with planting soil. 3. Gently drop flat to settle soil, add soil if necessary. 4. Create holes in the soil about 1-2” apart, and about 2 times the depth of the size of the seed. (if the seed is 1/8” how deep should the hole be?) Use your finger, stick or pencil. 5. Place a seed in each hole, if using a winged seed place the seed side down and the wing up (imagine the seed flying to earth). Gently will the hole with soil and let soil settle naturally. 6. Cover with fine crushed leaves of parent plant (if possible, or use maple leaves). Cover entire flat or pots with seed cloth. 7. Label pots with name of seed and date. 8. Water gently.