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Viola (pensylvanica)

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

Family Scientific Name: Violaceae
Family Common Name: Violet Family
Scientific Name: Viola pensylvanica Michaux
Common Name: Yellow violet
Species Code: VIPE4
General Distribution: Damp woods, cool slopes, in rocky places. Beech-hardwoods, persisting after clearing. Small, with 1-3 small kidney-shaped basal leaves. Whole plant becomes quite glabrous. Yellow flowers.
Propagation Goal: plants
Propagation Method: seed
ProductType: Container (plug)
Time To Grow: 0
Propagule Collection: Seed capsules are explosive and seed is difficult to collect. Seed is collected by hand from locally native plants within the eastern central Upper Peninsula. Flowers from April to June. Seed is harvested in July. Seed is an achene.
Propagule Processing: Dry seeds for 1-2 weeks in open paper bags or open Rubbermaid-style bins, shaking or turning seed heads. Seeds are not cleaned. Once seeds have dried begin stratification.
Pre-Planting Treatments: Stratification: mix the seeds with an equal amount of moist perlite or vermiculite. Put mixture into a Ziploc-style bag or a Rubbermaid-style container. Seal the container and store for at least three months 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 size plug. 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 and 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 plug cells again. Sow the seeds by hand at a rate of about 2 seeds in each cell. Leave the seeds on the surface of the soil as they need light to germinate. Sow year-round due to low variable success rates.
Establishment Phase: From Jan. until 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. through Dec. the thermostat is set at 55 degrees F. Duringthis season ambient greenhouse temperatures may reach 75 degrees F. during the day. 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. The greenhouse holds plants at all stages of growth so the temperature setting stays the same for all plants at all stages of growth. Plant trays are moved 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. When 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: Grows in mostly shady areas. Low germination success. Seed is ant dispersed. Ripening seed must be carefully watched to ensure collection.


Schultz, Jan; Beyer, Patty; Williams, Julie. 2002. Propagation protocol for production of Container (plug) Viola pensylvanica Michaux plants USDA FS - Hiawatha National Forest Marquette, Michigan. In: Native Plant Network. URL: http://NativePlantNetwork.org (accessed 2020/08/11). US Department of Agriculture, Forest Service, National Center for Reforestation, Nurseries, and Genetic Resources.

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