Giant Hyssop Agastache 'Blackadder'
ABOUT
Agastache 'Blackadder', also known as Giant Hyssop, is a plant that displays a striking appearance. The foliage of this plant is notable for its lance-shaped leaves, which are arranged in opposite pairs along the squared stems, exuding a fragrant aroma when crushed. The leaves usually boast a bright green hue that serves as a perfect backdrop for the flower spikes. The most eye-catching feature of the Giant Hyssop is its long, slender spires of flowers that bloom at the top of the stems. These blooms are typically a deep violet-blue color, creating a bold and vivid contrast against the greenery below. Each individual flower is tubular and compact, forming dense, bottlebrush-like clusters along the vertical spikes. As the flowering season progresses, from midsummer into fall, the plant continues to produce new blooms, which invites a constant buzz of pollinating insects, particularly bees and butterflies, drawn to its nectar-rich blossoms. Giant Hyssop's overall look is upright and clump-forming, which allows it to stand out in garden borders and flower beds where its richly-hued blooms can make a dramatic statement. The plant's aroma, color, and structure make it a favorite choice for gardeners looking to add both visual interest and wildlife value to their landscapes.
About this plant
NamesFamily
Lamiaceae
Synonyms
Giant Hyssop, Hummingbird Mint, Anise Hyssop
Common names
Agastache 'Blackadder'
ToxicityTo humans
The plant commonly known as Giant Hyssop (Agastache 'Blackadder') is not known to be toxic to humans. Typically, members of the Agastache genus are considered to be safe and are even used in culinary applications for their flavorful leaves. However, as with any plant, individuals may have allergic reactions or sensitivity to it, so it's always wise to exercise caution and not consume plants unless you are certain they are safe to eat.
To pets
Giant Hyssop (Agastache 'Blackadder') is not reported to be toxic to pets, including cats and dogs. This plant is often used in gardens for its attractive flowers and pleasant aroma, and there are no widespread reports of it causing harm to animals. As with any non-food plant, if a pet ingests a large amount of this plant, it might experience mild gastrointestinal upset simply because it is not part of the animal's typical diet. If any unusual symptoms do occur after ingestion, it is advisable to contact a veterinarian.
CharacteristicsLife cycle
Perennials
Foliage type
Deciduous
Color of leaves
Green
Flower color
Blue
Height
3-4 feet (0.91-1.22 meters)
Spread
1-2 feet (0.30-0.61 meters)
Plant type
Herb
Hardiness zones
5
Native area
North America
Benefits
General Benefits- Attractive to Pollinators: Agastache 'Blackadder', commonly known as giant hyssop, is highly attractive to bees, butterflies, and hummingbirds, encouraging biodiversity in the garden.
- Drought Tolerant: Once established, giant hyssop can tolerate periods of drought, making it a low-maintenance choice for water-conserving landscapes.
- Long Blooming: Giant hyssop has a long blooming season, providing flowers from midsummer to early fall and offering sustained visual interest.
- Deer Resistant: This plant is generally resistant to deer, which makes it an ideal choice for gardens in areas where deer browsing is a problem.
- Herbaceous Fragrance: The leaves and flowers emit a pleasant, aromatic scent that can add an extra layer of sensory enjoyment to a garden.
- Low Maintenance: Giant hyssop requires minimal care once it's established, needing only occasional deadheading and infrequent division.
- Edible Uses: The flowers and leaves are edible and can be used to flavor drinks and dishes, although this list focuses on non-medical benefits.
- Landscape Versatility: Giant hyssop can be used in a variety of landscape settings, including borders, beds, and as part of a perennial planting scheme.
Medical PropertiesThis plant is not used for medical purposes.
Air-purifying QualitiesThis plant is not specifically known for air purifying qualities.
Other Uses- As a natural dye: The leaves of Blackadder can be used to create a natural dye for fabrics, yielding various shades of yellow, green, or brown depending on mordants used.
- Bookbinding: The stems of Blackadder, with their sturdy nature, can be woven into unique, textured covers for handcrafted journals or books.
- Culinary presentation: The vibrant flowers can be used as an attractive, edible garnish in culinary dishes, adding a splash of color to salads and desserts.
- Artistic inspiration: The striking appearance of Blackadder can be used by artists as a subject for botanical illustrations and garden-inspired artwork.
- Crafts: Dried Blackadder flowers and leaves can be incorporated into potpourri mixes, offering a subtle visual appeal and a mild fragrance to homemade blends.
- Photography: Blackadder provides an attractive backdrop or focal point for garden photographers, especially when capturing pollinators in action.
- Educational tool: The plant can be included in horticultural therapy programs, teaching individuals about plant care and the growth habits of herbaceous perennials.
- Fragrance sachets: The leaves and flowers, when dried, can be used to fill sachets to freshen drawers and wardrobes with a mild, herby scent.
- Companion planting: Blackadder can be used in the vegetable garden to help attract pollinators, potentially increasing the yield of crops that require pollination.
- Garden design: The plant's vertical growth habit and dark flower spikes can offer structure and contrast in ornamental garden beds and borders.
Interesting Facts
Feng ShuiThe plant Agastache is not used in Feng Shui practice.
Zodiac Sign CompitabilityThe plant Agastache is not used in astrology practice.
Plant Symbolism- Attraction: Often grown in gardens to attract pollinators like bees and butterflies, the Agastache 'Blackadder', commonly known as Giant Hyssop, symbolizes attraction and magnetism.
- Healing and Protective: Since many Agastache varieties are used in herbal medicine, the Giant Hyssop can symbolize healing and is believed to have protective qualities against negativity and illness.
- Harmony: The plant's minty fragrance and its use in teas can promote relaxation and a sense of calm, thus it can symbolize peace and harmony.
- Warmth: With its vibrant purple flowers that bloom in late summer, the Giant Hyssop can represent warmth and abundance, reflecting the peak of the growing season.
WaterGiant Hyssop should be watered deeply once a week, giving it about 1 to 1.5 gallons depending on the soil moisture and climate conditions. The soil should be allowed to dry out between waterings as these plants prefer well-drained soil and do not like to remain in overly wet conditions. During periods of drought or extreme heat, increase the frequency of watering to ensure the plant remains hydrated but be cautious to avoid waterlogging the soil.
LightGiant Hyssop thrives best in full sun conditions, receiving at least 6 hours of direct sunlight daily. An ideal spot for this plant is in an area where it can enjoy unfiltered sunlight throughout most of the day, although it can tolerate some light shade. Avoid deeply shaded areas, as inadequate light can lead to poor flowering and weak growth.
TemperatureGiant Hyssop can endure a wide range of temperatures, but it grows best when the temperature is between 60°F and 80°F. It can survive minimum temperatures down to about 15°F, making it suitable for gardens in USDA zones 5 through 10. In regions with extreme winter conditions, providing mulch can help protect the plant from freezing temperatures.
PruningGiant Hyssop should be pruned to remove spent flower spikes and encourage additional blooming throughout the growing season. It's also beneficial to prune in early spring to shape the plant and remove any dead or damaged growth from winter. Pruning is typically done after the last frost and can be repeated as flowers fade.
CleaningAs needed
SoilGiant Hyssop 'Blackadder' thrives best in well-draining soil with a pH range of 6.0 to 7.0. A good soil mix would consist of garden soil, compost, and perlite or coarse sand to enhance drainage. This plant prefers a loamy or sandy soil structure and does not do well in heavy, wet soils.
RepottingGiant Hyssop 'Blackadder' should be repotted every 2-3 years to refresh the soil and accommodate growth. Over time, the soil can become compacted and nutrient-depleted, so repotting will help maintain the plant's health.
Humidity & MistingGiant Hyssop 'Blackadder' is adaptable to a range of humidity levels and does not require high humidity to thrive. Average room humidity is generally sufficient for this plant.
Suitable locationsIndoor
Keep Giant Hyssop in bright light and well-drained soil.
Outdoor
Plant in full sun to partial shade in well-drained soil.
Hardiness zone
5-9 USDA
Life cycleThe Agastache 'Blackadder', commonly known as Giant Hyssop or Blackadder, begins its life cycle as a seed, which when sown, germinates in warm conditions with sufficient moisture. Upon sprouting, the seedling develops its first set of true leaves and, as it matures, enters the vegetative stage characterized by the growth of stems and foliage. The plant then enters the flowering stage during summer to fall, where it produces tall spikes with small, vibrant purple flowers that are attractive to pollinators like bees and hummingbirds. After pollination, the flowers may produce seeds that can be dispersed to generate new plants, completing the sexual reproduction cycle. As a perennial, the Blackadder will die back to the ground during cold winter months, with its roots surviving to send up new growth in the following spring. Over time, the plant may also spread through rhizomes, expanding its presence in the garden.
PropogationPropogation time
Spring-Early Summer
Agastache 'Blackadder', commonly known as Anise Hyssop or Giant Hyssop, is typically propagated by seed, but the most popular method is through stem cuttings, especially to maintain the specific characteristics of this cultivar. For propagation via stem cuttings, the best time is late spring to early summer. Choose a healthy, non-flowering stem and cut a 4 to 6-inch (10 to 15 cm) length just below a node. Strip off the lower leaves and dip the cut end in rooting hormone powder to encourage root growth. Insert the cutting into a pot filled with a mix of half peat and half perlite, ensuring at least one node is buried where leaves were removed. The cutting should then be placed in indirect light and kept consistently moist. In a few weeks, roots will develop, and the new Anise Hyssop can eventually be transplanted outdoors.
