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Giant hyssop
The Agastache 'Black Adder', commonly known as giant hyssop, is a stunning perennial that brings a burst of deep blue and purple hues to any garden space. This hardy plant, with its spiky inflorescences, thrives in well-drained soils and sunny locations, attracting pollinators and adding vibrancy throughout the blooming months of July to September. The fragrance of the Agastache 'Black Adder' is as delightful as its visual appeal, making it a dual sensory experience.
We would like to provide some tips on how to plant and care for a Full-sun herb plants. By following these tips, you can be sure to enjoy your Full-sun herb plants for a long time.
Agastache 'Black Adder' flourishes best when positioned in full sun, where its vibrant blue and purple flowers can attract pollinators throughout its blooming period from July to September. While adaptable to various soil conditions, well-drained soil is crucial for the health of the plant. Ensuring the soil is not overly moist will cater to its average water needs and prevent issues associated with waterlogging. The fragrant and bushy growth habit of this species makes it an excellent choice for borders and group plantings, where it can reach its ultimate height of 80 cm and spread its delightful aroma.
For successful establishment, Agastache 'Black Adder' should be planted in well-drained soil and positioned to receive full sun, which is crucial for the development of its vivid blooms. Planting should be done with care, ensuring each pot-grown specimen has enough space to reach its mature height of approximately 80 cm and an upright, bushy form. Adequate watering upon planting and regularly thereafter is key, as the species has average water needs and is not drought resistant. To promote robust growth, consider the optimal planting period during the milder temperatures of spring or autumn.
Pruning is a vital part of caring for Agastache 'Black Adder', encouraging a compact and bushy growth habit. It is best to prune in early spring, cutting back the previous year's growth to a set of strong, fresh buds. This will stimulate the plant to produce robust new stems, which will bear the striking blue and purple flowers in the summer. Deadheading the spent blooms can prolong the flowering period, ensuring a continuous display of vibrant colors.
Agastache 'Black Adder' appreciates consistent moisture, especially during the flowering period from July to September. Regular watering will help maintain its lush foliage and support the vibrant blue and purple inflorescences. It is important to ensure the soil is well-drained to prevent waterlogging, which could adversely affect the plant's health. During establishment, water the plant deeply to encourage the development of a robust root system. Once established, this perennial may tolerate occasional dry spells, but should not be left to dry out completely. In the peak summer heat, monitor soil moisture closely and water as needed to keep the plant thriving.
To flourish and maintain robust growth, Agastache 'Black Adder' benefits from regular fertilization. Opt for a balanced granular or liquid fertilizer, applying it at the start of the growing season in early spring and once more during the midsummer to support prolonged flowering. The application of fertilizer should be according to the manufacturer's guidelines to prevent over-fertilization, which can lead to excessive foliage at the expense of blooms.
A well-timed feeding regimen ensures that this species has the necessary nutrients to sustain its upright to bushy growth habit and the production of its striking blue and purple flowers. Additionally, a fall application of compost or a slow-release fertilizer can help prepare the plants for the following growing season, strengthening their resilience and vitality.
Agastache 'Black Adder' thrives when planted in well-drained soil and a sunny spot, which enhances its vibrant blooms and aromatic foliage. This species is a favorite among pollinators, offering a rich nectar source for bees and butterflies. Its long blooming season extends from midsummer into the fall, providing an enduring splash of color. Additionally, the plant's upright habit and striking purple flowers make it an excellent choice for adding vertical interest to borders and garden designs.
To ensure robust growth and vitality, division of Agastache 'Black Adder' is recommended every few years. This rejuvenation process is best carried out in the cooler months of spring or autumn. Carefully uplift the entire specimen from the soil and gently separate it into smaller, manageable sections, each with a fair share of roots. Replant these divisions promptly, allowing ample space for them to expand and flourish. This method not only stimulates new growth but also helps maintain the health and vigor of this fragrant, upright to bushy species.
Agastache 'Black Adder' typically grows to a height ranging from 50 centimeters to 1 meter.
Agastache 'Black Adder' achieves a final spread ranging from 10 centimeters to 50 centimeters.
Agastache 'Black Adder' is adaptable to various soil types, but it thrives best in well-drained soil. This type of soil allows for proper moisture regulation and encourages healthy growth for the Agastache 'Black Adder' plant.
The ideal location for Agastache 'Black Adder' is in a sunny area. This plant thrives best when placed in a spot that receives plenty of direct sunlight.
Agastache 'Black Adder' displays stunning flower colors in shades of blue and purple, adding a touch of elegance to its appearance.
Agastache 'Black Adder' is considered winter hardy, able to withstand temperatures ranging from -9.4°C to -3.9°C. This places it within the USDA hardiness zones 8b to 9a. As such, Agastache 'Black Adder' is well-suited for enduring the winter conditions within these zones.
Agastache 'Black Adder' is not an evergreen plant. This means that it sheds its leaves at certain times of the year and regrows them at other times.
Agastache 'Black Adder' matures and achieves its ultimate height within a span of two to five years, showcasing a moderate yet steady growth rate.
If we are proud of anything at Heijnen Plants, it is our plant packaging. We have developed our own unique way of packaging our 9x9 cm potted plants. After years of continued development and research, we managed to create packaging that allows plants to be delivered to your home undamaged and quickly through a parcel service. This makes us unique!
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If you have ordered large-sized plants or trees, we deliver them on sealed pallets and place them around your house or driveway. The pallets are sturdy and provide optimal protection for large-sized plants.
We deliver small or medium-sized plants in boxes. The size of the box depends on the size of the plant. We always make sure that the plant has enough space but still stands firmly in the box, so it cannot be damaged during transport.
Discover the allure of Agastache 'Black Adder', an exquisite addition to any garden. This plant boasts stunning violet-blue flower spikes that create a serene visual appeal. Not only is it aesthetically pleasing, but the species also exudes a delightful fragrance, attracting pollinators and enhancing biodiversity in your outdoor space.
