Sunset Hyssop Growing Tips

Agastache rupestris

Sunset Hyssop

Barry Winiker/Getty Images 

Sunset hyssop is a surefire way to attract hummingbirds to your garden. We have worked near it in a garden and these avian beauties would always be nearby. The vibrant pink, purple, and orange blossoms definitely catch your eye, adding pizazz to any yard. It is able to grow in many zones and soil conditions. We love how it smells like root beer. 

Latin Name

Agastache rupestris is the scientific name assigned to this species. It is included in the Lamiaceae (mint) family.

Common Names

Names for this plant include sunset hyssop, threadleaf giant hyssop, rock anise, hummingbird mint, and licorice mint.

USDA Hardiness Zones

Zones 4b-9 are suggested for this species. It is native to Arizona, Mexico, and New Mexico.

Size and Shape

At maturity, each vase shaped sunset hyssop subshrub will measure 2 feet high and 1-1.5 feet wide.

Exposure

Plant sunset hyssop in a sunny location. It can tolerate part shade if needed.

Foliage/Flowers

The leaves are fine-textured with a gray-green color. In the summertime, sunset hyssop is covered in trumpet-shaped flowers, each with shades of orange, pink, and purple.

Design Tips

This is a must for any hummingbird garden. Good companions include butterfly bush (Buddleja davidii), lavender (Lavandula angustifolia), and Russian sage (Perovska spp.). It is also a good choice to include in drought-tolerant gardens.

It is sure to become one of your favorite subshrubs in the garden. For most of the summer, it is covered in brilliantly colored flowers that attract hummingbirds, butterflies, and bees. Sunset hyssop fills the air with a wonderful aroma similar to root beer or licorice

Growing Tips

Water regularly for the first season to establish the root system. Make sure the soil is well drained, as sunset hyssop does not tolerate soil that is constantly wet. After it is established, it is very drought tolerant.

During spring, you can divide established plants and replant. This is an easy way to expand your garden at no cost.

Sow seeds directly in the garden during spring after the last frost or indoors about eight weeks before then. Thin to one plant every 18". You can also take cuttings to create new plants.

You can use sunset hyssop leaves to make herbal tea.

Maintenance/Pruning

Cut sunset hyssop almost to the ground at the beginning of spring. This will promote stronger and more vigorous growth. Deadhead spent flowers in summer to extend the blooming season and make the plant look tidy.

In colder regions, mulch with pea gravel during the winter. Do not use wood mulches; these tend to keep the soil below very moist, which this plant cannot tolerate.

Pests and Diseases

Sunset hyssop may be susceptible to mildews, rusts, and other fungi if summer conditions are hot and humid.