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Blue Boa Agastache
Agastache ‘Blue Boa’
Blue Boa Agastache is a great choice when you want the pollinator power of Agastache with bigger, bolder blue-purple flower spikes. It brings hummingbirds, bees, and butterflies into the garden, and the upright habit makes it easy to repeat through sunny beds. Give it sun, sharp drainage, and a light hand with water and fertilizer, and it will carry color deep into the warm season.
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Large Violet-Blue Agastache for Hummingbirds, Pollinators, and Sunny Borders
Blue Boa Agastache Delivers Big Color on Upright Flower Spikes
Blue Boa Agastache is a long-blooming perennial grown for its large violet-blue flower spikes, upright habit, and fragrant green foliage. Also known as Agastache Blue Boa, Blue Boa Hummingbird Mint, or Blue Boa Giant Hyssop, this colorful perennial brings strong vertical flower power to sunny borders from summer into fall.
The blooms are larger and showier than many softer blue Agastache varieties. Dense tubular flowers stack along upright spikes, creating a bold bottlebrush effect that stands out in pollinator gardens, cottage gardens, cutting gardens, dry borders, and mixed perennial beds. Use it where you want color, movement, and pollinator activity, without the high-maintenance of a high-maintenance plant.
A Hummingbird Mint That Keeps the Garden Moving
Blue Boa Agastache is a favorite for gardeners who want a lively summer garden. The nectar-rich tubular flowers attract hummingbirds, bees, butterflies, and other beneficial pollinators over a long bloom season.
Plant it where you can enjoy the activity up close, such as near patios, walkways, porches, and seating areas. Repeating Blue Boa in groups or drifts creates a stronger visual display and makes the flowers easier for pollinators to find. It pairs especially well with Echinacea, Rudbeckia, Yarrow, Catmint, Salvia, Bee Balm, Russian Sage, Lavender, and ornamental grasses.
Compact, Upright Growth for Borders and Containers
Blue Boa Agastache commonly grows about 2 to 3 feet tall and 18 to 24 inches wide, making it easy to fit into sunny perennial beds without overwhelming the planting. The upright habit gives the garden height and structure while still staying manageable.
Use Blue Boa in the middle of borders, in pollinator strips, along sunny walkways, in cottage-style beds, or in containers with excellent drainage. Its blue-purple flowers combine beautifully with yellow, orange, pink, white, silver, and burgundy companion plants.
Full Sun, Sharp Drainage, and Drought Tolerance Once Established
Plant Blue Boa Agastache in full sun for the strongest stems and heaviest flowering. It can tolerate light shade, but too much shade may reduce bloom and make the plant less sturdy.
Well-drained soil is essential. Agastache performs best in average to lean soil that does not stay wet, especially during winter. Once established, Blue Boa is drought-tolerant and handles heat well, making it a strong choice for sunny borders, low-water gardens, slopes, raised beds, and containers.
Deer Resistant, Rabbit Resistant, and Easy to Maintain
Blue Boa Agastache is generally considered deer-resistant and rabbit-resistant. Its aromatic foliage has a minty, anise-like fragrance when crushed, which makes it less appealing to browsing animals than many softer-flowering perennials.
Maintenance is simple. Deadhead spent flower spikes to keep the plant tidy and encourage continued bloom. In colder climates, leave stems standing through winter to help protect the crown, then cut back old growth in late winter or early spring before new growth begins.
| Hardiness Zone: | 5-9 |
|---|---|
| Mature Height: | 2 to 3 feet tall |
| Mature Width: | 18 to 24 inches wide |
| Sunlight: | Full sun preferred; tolerates light shade |
| Soil | Average to lean, very well-drained soil |
| Water | Water regularly during establishment; drought tolerant once established |
| Bloom Time / Color | Summer into fall; deep violet-blue to blue-purple tubular flowers on large upright spikes |
| Foliage: | Fragrant green foliage with minty, anise-like scent when crushed |
| Ornamental Features | Large violet-blue flower spikes, upright habit, fragrant foliage, long bloom season, strong vertical color |
| Wildlife Value | Attracts hummingbirds, butterflies, bees, and other beneficial pollinators |
| Resistance | Generally considered deer resistant and rabbit resistant; drought tolerant once established; heat tolerant |
| Landscape Uses | Pollinator gardens, hummingbird gardens, sunny borders, cottage gardens, cutting gardens, dry gardens, herb gardens, mass plantings, containers |
How to Care for Blue Boa Agastache
Be sure to read our planting instructions to ensure a healthy and happy Blue Boa Agastache for years to come!
How should I plant Blue Boa Agastache?
Plant Blue Boa Agastache in full sun with well-drained soil. Dig a hole about twice as wide as the root ball and just as deep as the container. Set the crown level with the surrounding soil, backfill with loosened native soil, and water thoroughly after planting. Space plants about 18 to 24 inches apart so each clump has room for mature growth and good airflow. Avoid low, wet areas or heavy clay that stays soggy through winter. If drainage is a concern, plant Blue Boa in a raised bed, slope, berm, or container.
How often should I water Blue Boa Agastache after planting?
Water Blue Boa Agastache deeply after planting, then keep the soil lightly moist while the roots establish. During the first growing season, water when the top few inches of soil become dry, especially during hot or windy weather. Once established, Blue Boa Agastache is drought-tolerant and usually needs less supplemental water than many flowering perennials. Water deeply but infrequently during extended dry spells, and avoid frequent shallow watering or soggy soil.
When should I fertilize Blue Boa Agastache?
Fertilize Blue Boa Agastache lightly in spring only if the soil is very poor. A thin layer of compost or a modest application of slow-release balanced fertilizer is usually enough. Avoid heavy feeding. Agastache often performs best in average to lean soil, and too much fertilizer can encourage soft, floppy growth. Full sun, sharp drainage, and moderate watering are more important than frequent fertilizing.
When and how should I prune / cut back Blue Boa Agastache?
Deadhead spent flower spikes during the bloom season to keep Blue Boa Agastache tidy and encourage continued flowering. Cut individual flower stems back to a lower set of leaves or side shoots. In late winter or early spring, cut old stems back close to the ground before new growth begins. In colder regions, leave stems standing through winter for extra crown protection and beneficial insect habitat, then clean up once spring growth starts.
