Agastache nepetoides (Giant Yellow Hyssop)

Britton, N.L., and A. Brown. 1913.  An illustrated flora of the northern United States, Canada and the British Possessions. 3 vols. Charles Scribner’s Sons, New York. Vol. 3: 111. Provided by Kentucky Native Plant Society. Scanned by Omnitek Inc.

Where Commonly Found: Extremely RARE in CT, VT, disturbed sites, forest edge, open woodlands and rocky slopes.

How to Identify:
(For unfamiliar words: Wikipedia Glossary of Botanical Terms).
Go Botany Key for Agastache nepetoides.
Illinois Wildflower’s description of Agastache nepetoides.  Click on more images.

Flower Color:   Greenish Yellow to Brown
Flower Type:  Spikes
occurring terminally on central and major secondary stems.  Spikes are 4″-16″ long (quite variable in length, depending upon plant maturity) and .75″-1″ wide.  Flowers are densely crowded on the spike with only a few in bloom at a time.  Each flower is a tubular corolla, with 2 upper lobes, and about .3″ long with a tubular calyx, about .25″ long, with 2 upper lobes, 2 lateral lobes and a single lobe which is the largest.  Each flower has 4 stamen and 1 divided stamen that exert far beyond the corolla lip.
Flower Time:  July – September
Leaf Arrangement:  Opposite on minimally branched central stem that is light green, glabrous, 4-angled, with strong wings.
Leaf Type:  Simple, up to 6″ long and 3″ across with petioles up to 2″ long.  Leaves are lanceolate-ovate or cordate-ovate, medium to dark green, hairless or nearly so with coarsely serrated margins.
Height: 4′-7′
Seed Collection:   AS THIS PLANT IS RARE OR ENDANGERED IN PARTS OF OUR REGION PLEASE FOLLOW GUIDELINES BY THE CENTER FOR PLANT CONSERVATION.  Nutlets in groups of 4 replace each flower which are short-lived.

Attracts:  Bees, bumblebees, butterflies.
Use:  Open woodland garden.
Light:  Full to Part Sun
Hardiness Zone:  2-8  USDA Zone Map
Soils:  Medium
Notes:  Very attractive to pollinators, extremely rare in New England,  much more common in the Mid-West.VT,
Native to: RARE AND/OR ENDANGERED in parts of VT, NY, MA and CT.  Native in MA and much of the Mid-West and South.  Biota of North America, North American Plant Atlas.

Requested by Bronx River Wildflower Corridor, Roseanne Andrade.

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