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Asclepias (syriaca)

Jan Schultz
Forest Plant Ecologist
USDA FS - Hiawatha National Forest
1030 Wright Street
Marquette, Michigan 49855
906.228.4484 (fax)

Family Scientific Name: Asclepiadaceae
Family Common Name: Milkweed Family
Scientific Name: Asclepias syriaca L.
Common Name: Common Milkweed
Species Code: ASSY
General Distribution: Habitat is dry to somewhat moist, usually sandy, often disturbed areas. Roadsides and railroads, shores, dunes, fields, waste ground, openings in aspen and pine woodlands. Stout, finely downy, grayish-green, usually unbranched stem up to 2 meters tall. Rapidly spreading by underground stems.
Propagation Goal: plants
Propagation Method: seed
ProductType: Container (plug)
Time To Grow: 0
Propagule Collection: Seed is collected by hand from locally native plants within the eastern central Upper Peninsula. The plant blooms from approximately June to Aug. Follicles (pods) which are warty or tuberculate. Each seed has a coma or tuft of hair. Seed harvested Sept. thru Oct.
Propagule Processing: Seed can be readily removed from ripe pod by cracking the pod and pulling the seed from one side of the pod, leaving the "parachutes" behind. Dry seeds for 1-2 weeks in open paper bags or open Rubbermaid-style bins. Once seeds have dried begin stratification.
Pre-Planting Treatments: Stratification: mix the seeds with an equal amount of moist perlite or vermiculite. Seal mixture into a Ziploc-style bag or a Rubbermaid-style container. One-month cold moist stratification in a cool dry place (refrigerator or cold garage). Cold store until planted (up to 3 years)
Growing Area Preparation/
Annual Practices for Perennial Crops:
Propagation Environment: Greenhouse film is made of Standard U.V. 3HL Clear 6 mil (J.R. Johnson's Greenhouse Supply Inc.). Fans run continuously to circulate the air. Vents open during the summer months for cooling. Container Type: grows best in 24 cell (2"diameter) 14"x8.5"x4" deep flats. Can be grown in virtually any plug size. Sowing Media: Scotts Redi-earth Plug and Seedling Mix. Contains vermiculite, and sphagnum peat moss. Soil is sterile.
Thoroughly moisten the soil with water, mixing in the water with a trowel. Cover the holes in the bottom/sides of the plug tray cells with newspaper so that the soil does not fall out. Fill cells with damp soil press soil down with a spoon. Refill the cell plugs with soil to the top, this time not pressing it down. Water the soil in the plugs again. Sow the seeds by hand at a rate of about 2 seeds in each cell. Cover the seeds with a thin amount of soil. Sow year-round due to low variable success rates.
Establishment Phase: From Jan. until Aug. thegreenhouse thermostat is set a 65 degrees F both night and day. Ambient greenhouse temperatures may reach 100 degrees F during the day in the summer. From Sept. thru Dec. the thermostat is set at 55 degrees F. During this season ambient greenhouse temperatures may reach 75 degrees F during the day. The greenhouse holds plants at all stages of growth so the temperature setting stay the same for all plants at all stages of growth. Soil is kept consistently damp during germination. Water using a fine mist or light hose setting only. Newly planted trays should be placed on the south side of the greenhouse. No artificial light is used.
Active Growth Phase: The soil does not need to be consistently moist. Move trays to cooler north greenhouse tables. No fertilizers are used.
Hardening Phase: In early-late spring, mature plants can be moved into a cold frame with a cover of material that diffused sunlight to prevent scorching of the plants. When the danger of frost has passed, leave plants outside. Water less frequently.
Harvesting, Storage and Shipping: In the Upper Peninsula, flats are transplanted into the field from late May to early October. Flats that are not planted in the summer remain in the greenhouse for another season.
Other Comments: Attracts monarch butterfly and others. Grows naturally in dry mesic areas on the edge of fields or pastures. Plugs very difficult to plant out and establish. When transplanting be careful as the roots are fragile. Germination is somewhat spotty. Spreads once well established. Better success with direct seeding.


Schultz, Jan; Beyer, Patty; Williams, Julie. 2001. Propagation protocol for production of Container (plug) Asclepias syriaca L. plants USDA FS - Hiawatha National Forest Marquette, Michigan. In: Native Plant Network. URL: http://NativePlantNetwork.org (accessed 2021/06/17). US Department of Agriculture, Forest Service, National Center for Reforestation, Nurseries, and Genetic Resources.

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