Understanding Agastache: which species and hybrids are the most appropriate for a native garden in Westchester County NY

Agastache derives from the Anciet Greek words for "very much" and "ear of grain", describing the flower spikes. It is a member of subfamily Nepetoideae which contains a large proportion of the world's aromatic culinary herbs. Within its subfamily, it belongs to the mint tribe and the catmint subtribe.

Agastache is divided into two sections - Agastache and Brittonastrum. Section Agastache (common name Giant Hyssop) occurs in and around western to central North America, extending across the Bering Strait into East Asia. Section Brittonastrum (common name Hummingbird Mint) is found in and around southwestern North America, with the highest diversity in the uplands of northern Mexico.

Generally the Agastache group is more cold hardy, while the Brittonastrum group is more drought tolerant.

Some of the species and hybrids from the Agastache section

Agastache rugosa (Korean Mint; Wrinkled Giant Hyssop) is an upright, clump-forming, herbaceous perennial that typically grows to 2-3' tall. Leaves and flowers are aromatic. It is native to moist grasslands, valleys and stream banks in China, Vietnam, Laos, Korea and Japan. Violet-pink flowers bloom summer-to-fall atop strong, rigid stems.

Agastache foeniculum (Anise Hyssop) is native to parts of the upper Midwest and Great Plains (Wisconsin to Ontario west to British Columbia and south to Colorado). It is typically found in prairies, dry upland forested areas, plains and fields. It grows to 2-4 ft tall with a mid- to late summer bloom of lavender to purple flowers.

Agastache X Blue Fortune (Common Name: Anise Hyssop)

'Blue Fortune' is a cross between A. rugosa and A. foeniculum. It was bred and selected by Gert Fortgens of the Arboretum Trompenberg in Rotterdam, Netherlands. It is a tremendously long bloomer that produces lavender blue, bottlebrush-like flowers on strong, upright stems from midsummer to early fall.

Agastache rugosa ‘Blue Boa’ PP24050 Granted 2013

Assignee: Terra Nova Nurseries (Canby, OR)
Inventor: Harini Korlipara (Canby, OR)
'Blue Boa' is characterized by large deep purple blue flowers, a long bloom time, a stiffly upright, medium habit, and excellent vigor.

From the Plant Patent

This new variety is a selection out of a breeding line using Agastache rugosa as a parent to provide cold hardiness and wet soil tolerance. This seedling was selected for its deep purple blue color and good habit. The exact parents are unknown.

Compared to Agastache ‘Blue Fortune’ and ‘Black Adder’, both unpatented plants, the new cultivar has deeper purple blue flower color, wider flower spikes, and a shorter habit.

§ Cold hardiness.—USDA Zone 6-10.

§ Size.—Grows to 18 in wide and 30 in tall to the top of the flowers.

§ Vigor.—Excellent.

§ Stamen description.— ... pollen White in a moderate amount.

§ Fragrance.—Light herbal.

§ Lastingness.—A spike blooms for about 3 weeks on the plant.

§ Fruit/seed: 4 nutlets

Agastache rugosa 'Little Adder' PP26514 Granted 2016

Inventor: Scott Trees (Arroyo Grande, CA)

‘Little Adder’ is characterized by its medium violet-colored flowers, dark green-colored foliage, and moderately vigorous, upright-mounded growth habit.

From the Plant Patent:

The new cultivar originated in a controlled breeding program. The objective of the breeding program was the development of Agastache rugosa cultivars having a more compact and better-branched growth habit.

The new Agastache cultivar is the result of open-pollination. The female (seed) parent of the new cultivar is ‘Heronswood Strain’, not patented, characterized by its medium violet-colored flowers, dark green-colored foliage, and vigorous, upright growth habit. The male (pollen) parent of the new cultivar is unknown.

Plants of the new cultivar differ from plants of the female parent primarily in having a less vigorous and more mounded growth habit. Of the many commercially available Agastache cultivars, the most similar in comparison to the new cultivar is ‘Black Adder’, not patented. However, in side by side comparisons, plants of the new cultivar differ from plants of ‘Black Adder’ in at least the following characteristics:

1. Plants of the new cultivar are shorter than plants of ‘Black Adder’; and

2. Plants of the new cultivar are better-branched than plants of ‘Black Adder’.

Elements of the Detailed Description:

§ Size.—Height from soil level to top of plant plane: Approximately 21 in. Width: Approximately 20 in.

§ Branching habit.—Freely branching. Pinching enhances lateral branching. Quantity of branches per plant: Approximately 4 main basal branches with laterals forming at each node.

§ Flowering habit.—‘Little Adder’ is freely flowering, blooming from late spring through autumn

§ Reproductive organs.— ... Pollen amount: Moderate.

§ Seed and fruit production: Neither seed nor fruit production has been observed.

Note: Agastache rugosa 'Heronswood Strain' was collected from Korea by Dan Hinckley

Agastache hybrid 'Violet Vision' PP25274 Granted 2014

Applicant: Terra Nova Nurseries (Canby, OR) Inventor: Janet N. Egger

'Violet Vision' is characterized by large violet blue flowers, a long bloom time, a short, compact habit, good winter hardiness, and excellent

From the Plant Patent:

This new variety is one of several selections of new Agastache using Agastache cusickii and A. rugosa in the breeding lines to provide hardiness and compactness.

The new cultivar is a selection from the cross between the proprietary seedlings 09-02T, as the seed parent, and (08-2T×08-1T)#8, as the pollen parent. The new cultivar was selected for its compact habit, hardiness, and violet blue flowers.

Compared to the seed parent, Agastache 09-02T (unpatented) the new cultivar is shorter and has violet blue rather than purple blue flowers.

Compared to the pollen parent, Agastache (08-2T×08-1T)#8 (unpatented), the new cultivar has violet blue rather than white flowers and is taller and upright rather than prostrate.

§ Cold hardiness.—USDA Zone 6-10.

§ Size.—grows to 10 in wide and 23 in tall to the top of the flowers.

§ Vigor.—excellent.

§ Fragrance.—aromatic.

§ Lastingness.—a spike blooms for about 4 weeks on the plant.

§ Fruit/seed: 4 nutlets, 1 mm long, ovoid

One of the ‘Violet Vision’ parents:

Agastache cusickii (Cusick's Giant Hyssop) is native to ID, OR, MN and NV. It grows 4-8 in tall, spreads by stolons, and has relatively small flowers with purple-tipped sepals and white corollas. This plant grows in sagebrush and alpine ecosystems - dry, rocky mountain habitat.

Agastache scrophularifolium (Purple Giant Hyssop) sets soft plumes of the palest purple flowers that top out at 6 feet. The individual blossoms open over a period of several weeks summer through fall. That long bloom time, combined with high nectar content, makes this plant highly attractive to bees and butterflies, including the federally-endangered Rusty Patched Bumblebee. Birds feed on the seeds that follow. The sturdy, square stems support foliage that turns a rich brown and provides upright interest throughout the winter months.

It can be cut back in late spring to reduce overall plant height and encourage a bushier appearance.

Purple Giant Hyssop grows throughout the US and Northern Ontario, CN. Its native habitat is riparian buffers, disturbed open areas and meadows. It is sensitive to competition and tends to grow best and persist longest in areas where it does not have to interact with non-native competitive plants. However, its range is now severely reduced in many areas and in some cases extirpated completely. These declines are largely due to habitat loss, predation by deer, and competition for resources with non-native plants. It is listed as endangered in CT and MA, as threatened in MD and VT, and as a special concern in KY and TN. It grows in full and partial sun conditions and blooms July - October.

Agastache nepetoides (Yellow Giant Hyssop) grows 4-7 ft tall with very little branching. “An exclamation point throughout the landscape”. The leaves do not have the fragrance usually associated with some other members of the mint family, but they do have a bitter taste that makes them unpalatable to deer. The terminal flower spikes are about 4-16 in long and ¾–1 in across; the length of each spike is highly variable. The flowers are densely crowded together all around the spike, although only a few flowers are in bloom at the same time - that makes the flower not particularly showy. The bloom period lasts 1 - 2 months from mid-summer to early fall. Blooms are borne on sturdy stems. At maturity, each flower is replaced by 4 nutlets. The seeds can germinate freely. The root system is fibrous and rhizomatous - it can spread and form clonal colonies but is not characterized as being aggressive.

The beauty of the plant is in the toothed, arrowhead-shaped leaves, and it also has winter interest. It’s one of the plants that Piet Oudolf uses in some of his designs - in the picture below you can see it behind the Asclepius - the tallest guy.

Yellow Giant Hyssop is native to most of North America. It is listed as endangered in CT and GA, and as threatened in NY, VT and WI. Its native habitat includes deciduous woodlands, woodland borders and openings, thickets, meadows in wooded areas, and powerline clearances in wooded areas. Occasional disturbance is beneficial if it reduces, but does not eliminate, the shade from canopy trees and other kinds of woody vegetation. Yellow Giant Hyssop dislikes dry sunny areas, which will cause the foliage to wilt during a summer drought.

The flowers are visited by bees (e.g., honeybees, bumblebees, & Halictid bees), bee flies, and butterflies. These insects suck nectar, although some of the bees may collect pollen. Syrphid flies also visit the flowers to feed on pollen, but they are less effective at cross-pollination. The dense foliage of Yellow Giant Hyssop attracts its fair share of predatory insects, including parasitic wasps, spiders, ladybird beetles, and others.

Available from native plant nurseries in our area: Agastache X 'Blue Fortune' (New Moon has this on their native plant list; don't shoot the messenger); Agastache foeniculum; Agastache scrophularifolium; Agastache nepetoides

**Other Agastache taxa used for hybridization: From the Brittonastrum section**

Agastache pallidiflora (Giant Mountain Hyssop) produces a continual mass of lavender-rose, scented flowers from June to September. It’s extremely attractive to bees. It needs free-draining soil and full sun. It is native to AZ , CO , NM , TX and its native habitat is moist canyons. It grows up to 4 ft tall and has a range of flower colors from pink to purple.

The. 'Pink Pop' cultivar blooms from late spring to Autumn. Hardy to -10°F (Z7a - 10b). Drought tolerant; somewhat shade tolerant. Height: 10 - 12 in; Width: 8 - 10 in. Very long flowering and floriferous with pink-colored spikes. Fragrant.

Agastache cana (Texas Hummingbird Mint) is a very rare wildflower with aromatic, raspberry- pink flowers that cover the plant for several months in late summer. The flower spikes are up to 12 in long and the plant grows to 2 - 3 ft tall with a spread of 1.5 ft. The flowers are highly attractive to butterflies and hummingbirds. Butterflies are drawn in by the scent of the flowers, while hummingbirds are attracted to the sweet nectar and tubular-shaped blossoms of bright reds or purples. This species is generally found in New Mexico and Texas in southern mountains at elevations of about 5,000–6,000 ft. They can be found in crevices and cracks of granite cliffs or in canyon edges (dry slopes and neutral pH soil). Needs well-drained soil and full sun. Hardy to −20 °F.

Agastache pallida (Pale Giant Hyssop) (syn Agastache barberi) is native to AZ. Its native habitat is pine-oak woodlands, canyon bottoms in the shade of oaks. It grows up to 4 ft tall and has rose pink - magenta flowers.

Agastache rupestris (Giant hyssop or Threadleaf Giant Hyssop) is upright, clump-forming, and typically grows to 2-3 ft tall. It is native to cool mountain slopes (5000' to 7000' elevation) in Arizona and New Mexico. It has small salmon/burnt orange flowers and sometimes shows sporadic rebloom in fall if plants are cut back in late summer after the initial flowering period.
(Specific epithet means living on a cliff).

Agastache coccinea (Anise Hyssop or Orange-flowered Anise Hyssop) originated in the northwestern part of Mexico. This plant prefers full sun but can tolerate some shade. It will grow 2 - 3 feet tall and form a clump up to 2 feet wide. Showy, fragrant flowers appear from June to September. Deadheading will prolong the blooming period. The plant reseeds readily.

Agastache X 'Firebird' is a cross between A. coccinea x A. rupestris and features fragrant coppery-orange to coral flowers and aromatic gray-green foliage. It typically grows 2-3 ft tall. Flowers appear over a long June to September bloom period and are attractive to bees and butterflies.

Agastache X 'Ava' (Ava's Hummingbird Mint) is a hybrid between Agastache cana and Agastache pallida. It produces huge spikes of deep rose-pink flowers, raspberry-red calyxes and sweetly scented foliage. Flowering begins in mid-summer and continues for months, the spikes elongate up to a foot or more in length and intensifying in color with each passing week. "Unlike any other Agastache I've grown, Ava's calyxes retain their intense coloration keeping the plant beautiful until hard frost," says horticulturist David Salman. This plant takes two to three growing seasons to reach mature size and will live for many years when happy. Plant in enriched, well-drained garden soil. Leave the stems standing through winter. Cut back entire plant back to 3” in mid-spring (not in the fall). Grows 4 - 5 ft tall and about 2 ft wide. Zones 5 - 10.

**Newer cultivars from the Brittonastrum section of the species**

Agastache X 'SUMMER LOVE' PP 20510 Granted 2009

Inventor: Janet Egger

'Summer Love' is characterized by large, vivid purple flowers in large clusters, long bloom time, upright plant habit with dense branching, and excellent vigor.

From the Plant Patent

The new cultivar is a F2 selection from a planned breeding program. The original cross was between a dwarf form of Agastache pallidiflora ‘Pink Pop’ (an unpatented plant) as the seed parent and Agastache cana dark pink (an unpatented plant) as the pollen parent.

Compared to Agastache pallidiflora ‘Pink Pop’ dwarf, the seed parent, the new variety has brighter purple flowers with darker calyces, larger flowers and inflorescences. Compared to Agastache cana dark pink, the pollen parent, the new variety has denser inflorescences, with brighter, more purple, flower color, and a more compact habit.

 Bloom period.—June through frost in Canby, Oreg.

 Stamen description.— ... white pollen

 Fragrance.—strong, herbal.

 Lastingness.—a spike blooms for about 3 weeks on the plant.

 Fruit: 4 nutlets

 Seed: oblong, ... fertile

Agastache X 'KUDOS CORAL' PP25613 Granted 2014

Inventor: Janet Egger

'Kudos Coral' is characterized by coral red flowers in large inflorescences, a long bloom time, a very short, compact habit, good winter hardiness, and excellent vigor.

From the Plant Patent

This new variety is one of several selections of new Agastache using hardy and dwarf Agastache species in the breeding lines to provide hardiness and compactness. The new cultivar is a selection from the cross between the proprietary seedlings Agastache 46-1, as the seed parent, and Agastache 53-3, as the pollen parent.

Compared to the seed parent, Agastache 46-1 the new cultivar is shorter and hardier with coral red flowers rather than orange.

Compared to the pollen parent, Agastache 53-3, the new cultivar is shorter and better branched.

Compared to Agastache ‘Red Fortune’, an unpatented plant, the new cultivar is much shorter.

 Cold hardiness.—USDA Zone 6-10.

 Size.—grows to 12 in wide and 14 in tall to the top of the flowers.

 Vigor.—excellent.

 Stamen description.— ... pollen White

 Fragrance.—aromatic.

 Lastingness.—a spike blooms for about 4 weeks on the plant.

 Fruit/seed: 4 nutlets, 1 mm long, ovoid, Black

Agastache X 'Mango Tango' PP28747 Granted 2017

Applicant: Walter's Gardens, Inc. (Zeeland, MI)

Inventor: Hans A. Hansen (Zeeland, MI)

'Mango Tango' has a compact, dense, rounded, well-branched habit. The flowers cover the top three-quarters of the plant, are large, light-peach to dusky-orange in color, in tightly clustered verticils over an extended period which is lengthened further by persistent dusky rose-colored calyxes.

From the Plant Patent

The new plant was the result of a single seedling selection from an open-pollinated cross ... between the proprietary, unreleased, hybrid, clone Agastache HK10-17-01 (not patented) as the female or seed parent and an unknown parent from a mixed isolation bed as the male or pollen parent.

In comparison to the seed parent, Agastache ‘Mango Tango’ is more compact and denser in habit and the flower color is more orange. The nearest comparison variety is ‘Peachie Keen’, which is not as compact or rounded in habit as the new plant, and ‘Mango Tango’ has a deeper shade of orange in the flowers than ‘Peachie Keen’. Compared to Agastache ‘Kudos Mandarin’, the new plant has lighter colored flowers with less reddish tinting. Compared to Agastache ‘Kudos Coral’, the new plant has lighter colored flowers with more peach to dusky orange. Compared to Agastache ‘Summer Sunset’, the new plant is not as broad in habit, is more densely branched and the flower color contains more peach tinting.

 Plant habit: Multi-stemmed herbaceous perennial, rounded, heavily branched;

 Plant size: Without growth retardants or pinching — about 12 to 18 in tall and 13 to 18 in across;

 Inflorescence: ... 400 flowers per main stem; each stem flowering for about 4 weeks but remaining effective for about 6 weeks or more with strongly pigmented persistent calyxes;

 Pollen.—Abundant;

 Fragrance: None detected

 Fruit: Two carpels;

 Seed: Nutlet

Agastache X 'Peachie Keen' PP25886 Granted 2015

Inventors: Hans A. Hansen (Zeeland, MI), Kevin A. Hurd (Merrillville, IN)

‘Peachie Keen’ has large peachy colored flowers in tightly clustered verticils. The plant habit is compact and upright with a long bloom time and usefulness in the landscape extended by the persistent and colorful mauve calyxes.

From the Plant Patent

The new plant was the result of a planned cross ... between Agastache X ‘Firebird’ (not patented) as the female or seed parent and Agastache X ‘Ava’ (not patented) in a mixed isolation bed as the male or pollen parent.

In comparison to the seed parent, Agastache X ‘Firebird’, the new cultivar ‘Peachie Keen’ has peachy-colored flower petals rather than the reddish orange flower petals of ‘Firebird’, and the flower buds on ‘Peachie Keen’ are more orange and less red than the buds of ‘Firebird’.

In comparison to the male plant in the isolation bed, Agastache X ‘Ava’, the new plant has flowers with much less red petals and calyxes with less intense red with a green undertone.

§ Plant size: 16 - 18 in tall and 18 in across;

§ Flower: ... each spike flowering for about 3 weeks but remaining effective for about 5 weeks or more with strongly pigmented persistent calyxes, individual flowers open for about 2 to 3 days;

§ Fruit: Two carpels

§ Seed: Nutlet; four; flattened ovoid

§ Fragrance: None detected from flower

Agastache X ‘Morello’ PP29527 Granted 2018

Assignee: Terra Nova Nurseries, Inc. (Canby, OR)

Inventor: Janet Egger (Wilsonville, OR)

'Morello' is characterized by red purple flowers in large inflorescences, blooms late spring until frost, a bushy, upright habit, attractive bronze foliage in cool and stress conditions, good winter hardiness, and excellent vigor.

From the Plant Patent

The parents of this new hybrid cultivar include the species Agastache cusickii, A. cana, and A. pallida. This new cultivar came out of the planned breeding program to develop new colors and habits in hardy types. The new cultivar is a selection from the cross between the proprietary seedlings 195-3, as the seed parent, and Agastache 273-2, as the pollen parent.

Compared to the seed parent, Agastache 195-3, the new cultivar is taller and hardier.

Compared to the pollen parent, Agastache 273-2, the new cultivar has rose purple flowers rather than pink.

Compared to Agastache ‘Bolero’, an unpatented plant, the new cultivar has more crowns and branching, larger flowers, and larger inflorescences.

 Cold hardiness.—USDA Zone 5-9.

 Size.—Grows to 22in wide and 32 in tall to the top of the inflorescences.

 Vigor.—Excellent.

 Inflorescence: ... Up to 700 flowers per spike.

 Stamen description.— ... pollen

 Fragrance.—Aromatic.

 Lastingness.—A spike blooms for about 4 weeks on the plant.

 Fruit/seed: 4 nutlets, 1 mm long, ovoid, low fertility.

… and the newest, patented in 2023, (drum roll please) ‘Queen Nectarine’ and ‘Royal Raspberry’

Agastache X ‘Queen Nectarine’ PP34896 Granted Jan 2023

Assignee: Walters Gardens, Inc. (Zeeland, MI)

Inventor: Hans A. Hansen (Zeeland, MI)

‘Queen Nectarine’ is medium-sized, with a dense, rounded, well-branched habit. The flowers cover the top two-thirds of the plant, are large, soft-peach colored, with mauve-colored calyxes in densely branched panicles over an extended period beginning in early summer.

From the Plant Patent

The new plant was the result of a single seedling selection from a cross ... between the proprietary, unreleased, hybrid, clone Agastache 11-28-1 (not patented) as the female or seed parent and the proprietary, unreleased, hybrid, clone Agastache HK10-18-50 (not patented) as the male or pollen parent.

In comparison to the new plant, the seed parent is slightly shorter and more open in habit range. The male parent has a different flower color and is more compact in habit.

The nearest comparison varieties known to the inventor are: ‘Peachie Keen’, ‘Mango Tango’, ‘Kudos Coral', ‘Kudos Mandarin’ and ‘Summer Sunset’.

‘Peachie Keen’ has a smaller habit in both height and width, and with less heavily-branched panicles. ‘Mango Tango’ has a significantly shorter and more compact habit, and the flowers are vibrant mango-orange colored. ‘Kudos Mandarin’ has deeper orange-colored flowers with a significantly smaller habit. ‘Kudos Coral’ has a narrower and smaller habit in both height and width, and the flower is more reddish-colored. ‘Summer Sunset’ is less winter-hardy, smaller and narrower in habit, and the flower color contains more orangish coloration. Both ‘Kudos Mandarin’ and ‘Kudos Coral’ have not overwintered under similar conditions where the new plant has survived the winter.

 Plant size: Without growth retardants or pinching—to about 36 in tall and 43 in across;

 Inflorescence: ... 2,000 to 3,000 flowers per main stem; terminal flowering portion about 9 in long and about 3 in across; each stem flowering for about 5 weeks but remain effective for about 6 weeks or more because of the strongly pigmented persistent calyxes; repeating if deadheaded;

 Pollen.—Abundant

 Fragrance: None detected;

 Fruit: Two carpels;

 Seed: Nutlet, typically one to two per naturally pollinated flower, ellipsoidal; about 1 mm long, 0.8 mm across and 0.5 mm thick;

 Resistance: ‘Queen Nectarine’ is resistant to Odocoileus hemionus browsing, and shows no susceptibility to Downy Mildew (Perononspora).

 Hardiness: The new plant has survived USDA hardiness zones 6 to 10 but has not been tested yet beyond these temperatures.

Agastache hybrid ‘Royal Raspberry’ PP 34910 Granted Jan 2023

Assignee: Walter’s Gardens, Inc. (Zeeland, MI)
Inventor: Hans A. Hansen (Zeeland, MI)

A new and unique cultivar of hyssop, Agastache plant named ‘Royal Raspberry’ with medium-sized, dense, mounded, well-branched habit and spring foliage color with burgundy cast. The large flowers of rosy-purple coloration begin in early summer and cover the top two-thirds of the plant. The effective flowering season is extended with burgundy-colored calyxes in densely branched panicles.

From the Plant Patent:

The new plant was the result of a single seedling selection from a self-pollination by the inventor of the proprietary, unreleased, hybrid, clone Agastache 14-8-1 (not patented).

In comparison to the new plant, the parent is shorter and more mounded in habit and the flower color is a lighter lavender-pink.

The nearest comparison varieties known to the inventor are: ‘Mango Tango’ U.S. Plant Pat. No. 25,747, ‘Rosie Posie’ U.S. Plant Pat. No. 25,857, ‘Kudos Ambrosia’ U.S. Plant Pat. No. 25,616, ‘Kudos Mandarin’ U.S. Plant Pat. No. 25,381, ‘Summer Sunset’ U.S. Plant Pat. No. 23,623, ‘Ava’ (not patented), ‘Desert Solstice’ (not patented), ‘Desert Sunrise’ (not patented) and ‘Bolero’ (not patented).

‘Mango Tango’ has a significantly smaller habit in both height and width and has flowers that are light-peach to dusky-orange. ‘Rosie Posie’ has a shorter and more compact habit, and the flowers are hot-pink colored. ‘Kudos Ambrosia’ has lighter-pink flowers from orangish-peach buds and the calyxes are not as dark. ‘Kudos Mandarin’ has deeper-orange-colored flowers with a significantly smaller habit ‘Ava’ has a height of 120 to 150 cm with a narrow upright habit and flowers that are deep rose-pink. ‘Summer Sunset’ is less winter-hardy, smaller and narrower in habit, and the flower color contains more orangish coloration. ‘Desert Solstice’ has a similar height, but more upright narrow habit and flowers that are rosy-pink and calyxes that are a rosy fuchsia. ‘Desert Sunrise’ has a habit that is about 120 cm tall while upright and 60 cm wide with flowers that are a lighter orangish-pink. ‘Bolero’ has is more mounded in habit and more compact, but has similar spring foliage color.

The new plant Agastache ‘Royal Raspberry’ is distinct from the parent and all other anise hyssop known to the inventor in the following combined traits:

1. Medium sized, dense, mounded, well-branched habit;
1. 2. Large flowers of rosy-purple coloration in densely branched panicles;
2. 3. Long bloom time with effectiveness extended by persistent, burgundy-colored calyxes;
3. 4. Flowers covering the upper two-thirds of the plant for about five weeks beginning in early summer;
4. 5. Foliage displays a burgundy cast in the spring.
Plant habit: Multi-stemmed herbaceous perennial, rounded, heavily branched;

Plant size: Without growth retardants or pinching—to about 81 cm tall and 78 cm across;
Roots: Fibrous, well-branched
Leaf fragrance: Moderately herbal, minty
Inflorescence: …Individual flowers open for about 3 days;… each stem flowering for about 5 weeks but remain effective for about 6 weeks or more with strongly-pigmented, persistent, burgundy-colored calyxes;
Bloom period: Early July through early fall
Pollen.—Abundant; color nearest RHS NN155C.

Flower fragrance: None detected;
Fruit: Two carpels
Seed: Nutlet, typically one to two per naturally pollinated flower
Resistance: ‘Royal Raspberry’ is resistant to Odocoileus hemionus browsing, and shows no susceptibility to Downy Mildew (Perononspora) but has not been tested or shown resistance to other pests and diseases common to Agastache.
Hardiness: The new plant has survived USDA hardiness zones 6 to 10 but has not been tested yet beyond these temperatures.

CONCLUSIONS?

If the garden is in Westchester County NY and you want to plant native Agastache for a pollinator garden, then I think it would be best to choose Agastache foeniculum or Agastache X ‘Blue Fortune’. The cultivars with striking violet flower color in the Agastache section are from A. rugosa, which is decidedly not native. From an ornamental perspective, though, they’re really nice and I have used and been very happy with both ‘Blue Boa’ and ‘Violet Vision’. ‘Blue Fortune’ can get a bit floppy in my experience. I’ve not seen A, foeniculum IRL so I don’t know how it behaves, but the pictures of the flowers look prettier than those of ‘Blue Fortune’ to me.

If you want to have a native Agastache with ecological benefit, and you’ve got a place for tall stuff that may or may not be ornamental enough for some gardens, then you might want to try either Purple Giant Hyssop or Yellow Giant Hyssop. Neither one has showy flowers, so if that’s important to the design, think twice. (On the other hand, Piet Oudolf uses Yellow Giant Hyssop!) For open meadows, woodland edges, but NOT dry sunny places.

If the garden is in Westchester County NY and you want to plant a dry garden in really good sun, then definitely try some of the plants from the Brittonastrum section. Some of the cultivars have orangey-salmony flowers and they all have a very different look than A. ‘Blue Fortune’. The flowers on these cultivars are not packed so tightly into the inflorescence, and some have interesting different colored calyxes. But in many places where I work, the soil is really too wet for these cultivars and they never make it through the winter. I’ll definitely try the new ones in the ‘Meant to Bee’ series (oy vey, branding is taking over the world) because they are supposedly more cold hardy and they look quite floriferous and I like both the colors. The peachy nectarine color is unusual and blends interestingly with other colors.