Giant hyssop (Agastache 'Summer Love')
Agastache 'Summer Love' (Giant hyssop) offers long-blooming reddish-purple spikes, requiring full sun and low maintenance.
Complete Plant Information
Overview
Agastache ‘Summer Love’, commonly known as Giant hyssop, is a standout herbaceous perennial prized for its extended blooming season and aromatic foliage. This hybrid variety brings vibrant, reddish-purple flowers atop stiff stems designed to attract hummingbirds and butterflies throughout the summer months and into fall. As an upright, clump-forming plant, Agastache ‘Summer Love’ provides excellent vertical accent in sunny garden locations.
This Giant hyssop variety typically reaches 2 to 3 feet tall, offering substantial visual impact without excessive bulk. Its success hinges on appropriate drainage, as the plant thrives in average, well-drained soils but struggles in heavy clay, which necessitates site selection carefully to ensure good winter survival. The low maintenance requirements and tolerance for heat make Agastache ‘Summer Love’ an excellent choice for gardeners seeking long-lasting color and high wildlife value.
Fast Facts
- Plant Family: Lamiaceae
- Plant Type: Herbaceous perennial
- Hardiness Zones: USDA Zones 6-9
- Size at Maturity:
- Height: 2-3 ft
- Spread: 1.5-2 ft
- Bloom Time: July to September
- Bloom Description: Reddish-purple
- Sun Exposure: Full sun
- Water Needs: Medium
- Maintenance Level: Low
How to Grow
Plant Agastache ‘Summer Love’ in the spring after the danger of frost has passed, aiming for locations receiving full sun exposure. The single most critical factor for success with Giant hyssop is ensuring very well-drained soils. While it tolerates average moisture conditions medium watering is sufficient once established, avoid areas where water pools, especially in heavy clay, as poor drainage leads rapidly to crown or root rot.
Maintenance for this perennial is generally low. Deadheading the spent flowers encourages the plant to continue producing its attractive reddish-purple blooms well into September. Fertilization is rarely necessary; over-fertilizing can sometimes lead to weaker stems and reduced flowering. Agastache hybrids perform best when they are not heavily pruned until early spring clean-up.
Winter care is important, especially in the northern reaches of its hardiness range (Zone 6). For maximum hardiness, site plants in protected areas, such as those with southern exposures. It is beneficial to resist cutting back the flower stems and leaf litter in the fall, as leaving this material in place provides insulation and protection over winter for the crown of the Agastache ‘Summer Love’.
Landscape Uses
The bold, aromatic nature of this Giant hyssop provides significant texture and long-lasting color ideal for sunny borders. Agastache ‘Summer Love’ works beautifully in cottage gardens where its vertical spikes mingle with softer, rounder blooms, adding height and structure. Due to its attractive flowers that draw in pollinators, it is an excellent feature plant for wildlife or butterfly gardens situated near patios or walkways where visitors can admire the activity.
Its stiff vertical habit makes it suitable as a non-hedge border plant along paths, providing aromatic interest when brushed against. Consider pairing the reddish-purple spikes of Agastache ‘Summer Love’ with plants that offer contrasting foliage color, such as silvery Artemisia or dark-leaved Salvias, to enhance the visual impact during its long bloom period. Furthermore, the flower spikes are highly regarded as good cut flowers for fresh arrangements.
Standout Features
Flower Qualities
- Showy
Noteworthy Characteristics
Agastache hybrids like ‘Summer Love’ often boast showier flowers combined with improved winter hardiness compared to older species. These plants are characterized by dense terminal spikes featuring tiny, two-lipped tubular flowers that create continuous color from mid-summer onward. The foliage is noteworthy for its fragrant, mint-scented nature, adding another sensory layer to this adaptable perennial.
Tolerances
- Deer
Potential Problems
Crown or root rot represents the most serious potential problem for Agastache ‘Summer Love’, developing exclusively in situations where soil drainage is inadequate. To prevent this, amend heavy soils thoroughly before planting. While generally pest-free, gardeners should monitor for signs of rust, powdery mildew, or leaf spots, which can occur, particularly in overly humid or crowded conditions. Ensuring good air circulation by allowing adequate space between plants helps mitigate fungal issues.
Frequently Asked Questions
What hardiness zones is Giant hyssop suitable for?
Agastache ‘Summer Love’ is hardy in USDA Zones 6 through 9, offering reliable return in these temperate to warmer regions.
How large does Agastache ‘Summer Love’ grow?
This perennial typically matures to a height between 2 and 3 feet tall, with a spread ranging from 1.5 to 2 feet wide, forming a tidy, upright clump.
What sun exposure does Giant hyssop need?
Agastache ‘Summer Love’ requires full sun exposure to achieve its best flowering performance and maintain strong, healthy growth.
When does Agastache ‘Summer Love’ bloom?
This long-blooming variety produces its distinctive garden color from July through September, featuring numerous spikes of reddish-purple flowers.
Conclusion
The combination of sustained reddish-purple bloom, drought tolerance once established, and strong resistance to deer makes Agastache ‘Summer Love’ a truly valuable addition to the sunny garden. This low-maintenance Giant hyssop brightens borders and supports local pollinators throughout the peak summer season. Check your soil drainage carefully and plant this versatile perennial in the warmest, sunniest spot you have available for guaranteed season-long enjoyment.
Wildlife Benefits
The tubular structure of the flowers on Agastache ‘Summer Love’ is perfectly shaped to cater to specific pollinators, making it a magnet for hummingbirds seeking nectar. Beyond hummingbirds, the dense flower spikes attract beneficial insects, including numerous species of bees and butterflies throughout the summer months. Integrating this Giant hyssop variety into your landscape actively supports local biodiversity.
Companion Planting
Due to its preference for full sun and sharp drainage, Agastache ‘Summer Love’ pairs well with other Mediterranean or drought-tolerant perennials. Consider pairing it with plants that have contrasting textures or colors, such as ornamental grasses like Stipa tenuissima, or sturdy companions like Salvia nemorosa cultivars or Echinacea for robust, hot-summer garden designs. Ensure these companions share the medium water needs of the Giant hyssop.
