blue giant hyssop

(Agastache foeniculum)

               
Conservation Status

IUCN Red List

not yet assessed

blue giant hyssop

NatureServe

NNR - Unranked

SNR - Unranked

Minnesota

not listed

Nativity

Native

Occurrence

 

Habitat

Dry to moderate moisture. Upland woods and prairies. Full or partial sun.

Flowering

July to August

Flower Color

Blue

Height

24 to 36


Identification

This is a 24 to 36 tall, erect, perennial forb that rises from a taproot.

The stems are erect, square, and occasionally branched above the middle. They are usually hairless, sometimes slightly hairy.

The leaves are opposite, egg-shaped to triangular egg-shaped or rhombic egg-shaped, up to 3½ long, and up to 2 wide. They are on leaf stalks that are no more than long. The leaf blades are broadly angled or squared off at the base and tapered to a point at the tip with straight or concave sides along the tip. The upper leaf surface is dull green and hairless. The lower surface is whitish due to a dense covering of microscopic, fine hairs. The hairs are barely discernible when using a hand lens with 10x magnification. The margins are coarsely toothed with sharp, forward-pointing teeth. The leaves emit a strong, anise-like odor when crushed.

The inflorescence is a dense spike at the end of the stems and branches. The spikes are up to 6 long, ¾ to 1 wide including the corollas, and are often interrupted at the base. The flowers are arranged in dense whorls that are subtended by hairless, broadly egg-shaped, abruptly tapered, inconspicuous bracts.

The individual flowers are about ½ long. There are 5 dull blue-violet sepals fused onto a ¼ to long calyx tube with 5 lance triangular-shaped lobes. The calyx tube is minutely hairy when in flower. There are 5 petals fused into a funnel-shaped corolla tube with a 2-lobed upper lip and a 3-lobed lower lip. The corolla is blue and extends well beyond the calyx. There are 4 stamens with purple anthers that protrude well beyond the corolla. After the corollas drop off, the spike that remains is blue-violet, not green or whitish. There is no floral scent.

The fruit is a more or less 3-sided nutlet.

 
Similar
Species

Purple giant hyssop (Agastache scrophulariifolia) is a much taller plant, 36 to 60 in height at maturity. The underside of the leaves are green, not white. The calyx is green and hairless. The individual flowers are white or pale pink to purple. The spike that remains after the flowers have dropped is green or whitish, not purple.


Distribution Distribution Map   Sources: 2, 3, 4, 5, 7, 28.

Comments

 


Taxonomy

Family:

Lamiaceae (mint)

 

Subfamily:

Nepetoideae

 

Tribe:

Mentheae

 

Subtribe:

Nepetinae

 
Synonyms

Agastache anethiodora

 
Common
Names

anise hyssop

anise-mint

blue giant hyssop

blue giant-hyssop

fragrant giant hyssop

lavender giant hyssop

licorice-mint


 

 

 

 

 

 

 

Glossary

bract

Modified leaf at the base of a flower stalk or flower cluster.

 

calyx

The group of outer floral leaves (sepals) below the petals, occasionally forming a tube.

 

corolla

A collective name for all of the petals of a flower.

       

Visitor Photos

   
Share your photo of this plant.

       
       
       
       

MinnesotaSeasons.com Photos

   

Plant

  blue giant hyssop   blue giant hyssop
       
  blue giant hyssop    
       

Inflorescence

  blue giant hyssop   blue giant hyssop
       
  blue giant hyssop   blue giant hyssop
       

Leaves

  blue giant hyssop    
       
       

 

Camera

     

Slideshows

   
  Agastache foeniculum
Susanne Wiik
 
  Agastache foeniculum  
 
About

Anisisop, Anise hyssop

 
     

 

slideshow

     

Visitor Videos

   
Share your video of this plant.

     
     

Other Videos

 
     
     
     
     

 

Camcorder

Last Updated:

About Us | Privacy Policy | Contact Us | © 2017 MinnesotaSeasons.com. All rights reserved.