Pycnanthemum virginianum

Common Mountain Mint

Family: The taxonomic plant family to which this plant belongs. Lamiaceae

Growth Form: Tree/shrub
Forb - non-woody flowering plant that is not a grass
Herb - a plant whose stem does not produce woody, persistent tissue and generally dies back at the end of each growing season
Graminoid - grasses and grass-like plants, such as sedges

Hydro Zone: The plant's preferred soil moisture zone relative to the lake's "NWL" (normal water level). For example: if a plant's hydro zone is shown as "NWL to +12," that plant can be planted in the zone beginning at the lake's normal water level and extending up to 12 inches (vertically) above the normal water level. Another example: "-3" to +6" would mean that plant prefers to be in water no more than three inches deep, and no higher than 6 inches (vertically) above the normal water level. NWL to +12"

NWC: The plant's classification as reported in Plants of the Chicago Region according to the National Wetland Category classification system.
OBL (Obligate Wetland): Occurs almost always in wetlands under natural conditions
FACW (Faculative Wetland): Usually occurs in wetlands, but occasionally found in non-wetlands
FAC (Faculative Wetland): Equally likely to be occur in wetlands or non-wetlands
FACU (Faculative Upland): Occasionally occurs in wetlands, but usually occurs in non-wetlands
UPL (Upland): Occurs almost never in wetlands under natural conditions

C-value: The plant's "Coefficient of Conservatism" as determined by Floyd Swink and Gerould Wilhelm in Plants of the Chicago Region. The number, on a scale from 0 to 10, represents an estimated probability that a plant species is likely to occur in a landscape relatively unaltered from what is believed to be a pre-settlement condition. A C value of 0 indicates the probability is almost 0, while a C value of 10 indicates the plant is almost certain to be found only in an undegraded natural community. 5

Max Height: The approximate maximum height of the plant growing in the Chicago region. 3'

Hardiness Zones: Established by the U.S. Department of Agriculture, the United States and Canada comprise 11 plant Hardiness Zones, based on average to low temperatures in winter. A plant's hardiness is the range of zones in which it will grow most successfully. Northeastern Illinois falls into Zones 5a and 5b. Click here for a more detailed discussion. 3 - 7

Light: The plant's light preference (e.g., full sun, light shade, part shade, shade, etc.) Sun - part shade

Bloom: The approximate bloom period for this plant in the Chicago region, derived primarily from Swink and Wilhelm's Plants of the Chicago Region. 22 June - 6 Oct

Collect Seed: The timeframe when the plant's seeds are usually ready for harvest in the Chicago region. Fall

Similar Species:

Distinguishing Characteristics: 2-3' tall, branching; Narrow, toothless, tapering leaves; Profuse, somewhat flat-topped, terminal clusters of small, white, 2-lipped flowers; All parts of plant emit strong mint scent when crushed.

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early growth

Early Growth

mid growth

Mid Growth

full growth

Full Growth





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Distinguishing Characteristic