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Gentiana (andrewsii)

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

Family Scientific Name: Gentianaceae
Family Common Name: Gentian Family
Scientific Name: Gentiana andrewsii Griseb.
Common Name: Closed or Bottle gentian
Species Code: GEAN
General Distribution: Marshy or at least moist ground; meadows and wet prairies; shores, thickets and ditches; river banks, floodplains, swamp forests. White or blue flowers. Each corolla lobe terminates in a small tooth or mucro. 14-30 inches tall.
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 of Michigan. Flowers in Aug.-Sept. Seed is an achene and is harvested in October-November.
Propagule Processing: Dry seeds for 1-2 weeks in open paper bags or open Rubbermaid-style bins. Seeds are very small and are not cleaned. Once seeds have dried begin stratification.
Pre-Planting Treatments: Stratification: Seal the seeds in a Ziploc-style bag or a Rubbermaid-style container with an equal amount of either perlite or vermiculite. Add just enough water to barely saturate the mixture and store in a refrigerator or cold garage (42 degrees F) for at least 3 months. 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. 3 HL Clear 6 mil from (J.R. Johnson's Greenhouse Supply Inc.) Fans run continuously to circulate the air. Vents open during the summer months for cooling. Container Type: 14"x8.5" trays having 24 cells, each cell being 2" in diameter and 4" deep. Growing Media: Scotts Redi-earth Plug and Seedling Mix. Contains vermiculite, and sphagnum peat moss. Soil is sterile.
Add enough water to the soil to saturate. Mix the soil with a trowel. Cover the holes in the bottom/sides of the plug tray cells with newspaper, as the soil will fall through. Fill cells with damp soil and press soil down with a spoon. Refill the cell plugs with soil to the top, this time not pressing it down. Thoroughly moisten soil in the plug cells, but do not saturate. Sow seeds by hand at a rate of about 3 seeds in each cell. Cover the seeds with a thin layer of soil or gently press the seeds into the dirt. Sow year-round due to variable germination rates.
Establishment Phase: From Jan. thru Aug. the greenhouse thermostat is set at 65 degrees F both day and night. 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 temperature may reach 75 degrees F during the day. The greenhouse holds plants at all stages of growth so the temperature setting stays 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 are 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 diffuses sunlight to prevent scorching of the plants. Once danger of frost has passed leave plants outside. Water less frequently.
Harvesting, Storage and Shipping: In the Upper Peninsula, flats are out-planted from late May to early October. Flats that are not planted in the summer remain in the greenhouse for another season.
Other Comments: Plant is difficult to grow.


Schultz, Jan; Beyer, Patty; Williams, Julie. 2001. Propagation protocol for production of Container (plug) Gentiana andrewsii Griseb. plants USDA FS - Hiawatha National Forest Marquette, Michigan. In: Native Plant Network. URL: http://NativePlantNetwork.org (accessed 2021/09/19). US Department of Agriculture, Forest Service, National Center for Reforestation, Nurseries, and Genetic Resources.

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